1979 GMC Dually TBI swap

[Randy 79]

This is kinda my build thread I guess, so I will update it as I go. I'm working on a 79 GMC Dually (http://shop.ebay.com/i.html?_nkw=gmc+dually) that I tow a 28ft enclosed trailer (http://shop.ebay.com/i.html?_nkw=enclosed+trailer) with. It was a 454 truck but has a 350 now. Still has the SM465 M/T in it, with 3.73 gears. It does a decent job pulling the trailer but the 350 works quite hard and slows down on hills. More power was needed. So, I picked up a 92 Suburban 4x4 Gen V 454 TBI (at machine shop, being rebuilt). I was going to run it carbed, but since I have to run an electric fuel pump (http://rd.bizrate.com/rd?t=http%3A%2F%2Fwww.partsgeek.com%2F7ykk1fc-ford-ranger-electric-fuel-pump.html%3Futm_source%3Dshopzilla%26utm_medium%3D pf%26utm_content%3Dmc%26utm_campaign%3DPartsGeek%2 BShopZilla%26fp%3Dpp%26utm_term%3D1985-1988%2BFord%2BRanger%2BElectric%2BFuel%2BPump%2B-%2BAirtex&mid=192248&cat_id=22000200&atom=10681&prod_id=&oid=4152474918&pos=1&b_id=18&bid_type=0&bamt=295d11ad54194830&cobrand=1&ppr=f5b0796e86f603b7&rf=af1&af_assettype_id=10&af_creative_id=6&af_id=6784), thought it might be good to use the TBI stuff it came with. Didn't hurt it came with an Edelbrock TBI intake, ported TBI with spacer and AFPR, air cleaner, wiring harness (http://shop.ebay.com/i.html?_nkw=wiring+harness), all sensors, and computer (7060, BANF chip). Since the truck is a manual, it will be fun to get everything to work together. I will need a new chip, may just get someone to make one for me to get it going.

I have already unwrapped the harness and removed the unnecessary wiring. I do want to keep the 4L80E wiring intact in case I decide down the road to go with overdrive. I still have quite a bit to figure out but I am getting there. I got a 92 wiring manual which has helped quite a bit and wiring diagrams from this site as well. Should be a fun project. I have previously swapped a 94 LT1 into a 67 El Camino with a Painless harness, so not totally green on EFI swaps.

I have a few questions, but I will have more later I am sure.

1. As for the speed sensor, can I wire it to the ECM, instead of using the DRAC that I got with the engine (no wiring to connect the DRAC, must have been part of the underdash harness)? If so, would a sensor like #2PRS from JTR work (2-pulse for TBI), or do I need a different one? It needs to work with the sM465 and my speedo cable.

2. Is there anything on the a/c that needs to go to the ECM, for idle control or anything else? Hard to tell from the 92 diagrams due to the electronic climate control the Suburban had.

3. I would like to put a hidden switch to the system as an anti-theft device. Is it best to put it on one of the ECM power leads or maybe on a random wire? Something to keep someone from starting the truck and driving off with it and my trailer.

4. I will be running dual fuel tanks, truck only has one tank now. Is it hard to put the selector valve in with TBI in tank pumps? What is a good pump to use? The adjustable fuel pressure regulator is set to 25 psi per the previous owner, would that affect pump selection?

5. Cam selection. The current cam in it is worn so I need to replace it. The previous owner (a friend) is pretty good with EFI stuff and had an unusual cam in it, at least to me. It had a Comp Cams 11-400-4 blower/turbo cam, specs here: http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=426&sb=0 It was run NA for 150K miles, so it did work. He said it had more mid-range torque than the TBI cams, and stopped pulling at 4800 rpms. Any thoughts on this? Of course we joked it would be good for adding boost to the 454, but I'm not sure if the injectors would be able to handle the extra fuel requirement. It will be NA for now, adding forced induction would be way farther down the road if ever.

[Randy 79]

Oh, here is a picture of the truck and the engine when I first got it.
http://i967.photobucket.com/albums/ae160/rjpajer/79%20GMC%20Dually/IMGA0350.jpg (http://s967.photobucket.com/user/rjpajer/media/79%20GMC%20Dually/IMGA0350.jpg.html)
http://i967.photobucket.com/albums/ae160/rjpajer/79%20GMC%20Dually/454tbi_zpse5379c51.jpg (http://s967.photobucket.com/user/rjpajer/media/79%20GMC%20Dually/454tbi_zpse5379c51.jpg.html)

[EagleMark]

Nice truck! :thumbsup:

Those cam specs look horrible without boost.

There are a couple bis to set/unset for VSS Drac or Mag so probably be able to run VSS to PCM without DRAC/VSSB, there's no need for signal to speedo on your truck or accurate speed for the E trans so I don't think that is a big issue.

Plumbing, switches and valves for duel tanks is an absolute nightmare and expensive, unless you find a dual tank truck at junk yard for all the parts!

Hidden kill switch is easy and can be done many differant ways.

There is a wire for A/C on and very easy to wire in.

But I don't think that PCM ever had a manual trans? Pretty sure not. You may be better off using the harness and wiring in another ECM? There's so much differant in man to auto bin files.

Hope that get's you started!

[Randy 79]

Thanks for the info Mark. I wasn't sure if the 7060 ECM could work with a manual, that may present a problem. So if I need to change the computer, which one should I get? Does it needs to be for a 92-93 TBI with manual. Since my harness doesn't have a connection for an external ESC, does that limit my computer choices? I believe I will have to change the pinouts for the different ECM as well.

This was one concern I had with using this TBI setup, that I would end up having to change parts out (cost more $$$$). I hoped to use what I had to keep costs down. Otherwise my backup plan is to go old school, as I have a carb and HEI distributor for it, I just need to get an intake manifold for it. I'll see what I am looking at cost wise with the TBI before the backup plan comes into play.

[Randy 79]

Well, after some searching, it looks like the 1228747 computer is the one to use with a manual trans. This should simplify the installation, price is pretty cheap for it, both at parts store and ebay (no core charges on ebay for the most part).

I have the wiring diagrams from this site so now to figure out what pinout changes I will have to make. Good thing I have time to figure this out, the 350 is getting the job done for now. More updates later.

[ony]

your wiring hornass don't have a spark control module plug ?

[Randy 79]

No it doesn't, ESC is in the ECM on the 7060. The 8747 doesn't have KS or ESC, so at least I shouldn't have any issues with that, hopefully (knocks on fake wood).

[Nasty-Z]

I would personally repin your harness and use the '7427 PCM , run it with your manual trans now and have the capability there for an '80E if you choose down the road .

Also, try if at all possible to run the knock sensor and system , especially if it will see towing / hauling duty , don't know why GM didn't use it on some , kinda weird.....

I would simply wire in the DRAC now , it is needeed for E trans control (as I have found out) and is much easie4r to add it now and not need it than to need it and not have it.

That cam , as Mark said , will be a dog without boost . If you are replacing it , I would go roller and not look back . Cant see the timing cover in the pic but you can either check that or the lifter valley , some very late GenV's were drilled and tapped for the roller lifter retainer , this was at the point they were getting ready to release the GenVI , timing cover would have 6 bolts and be either composite or aluminum. Might get lucky ......

The injectors will support a fair amount of boost (ask me how I know) , but be warned the 3764 intake will be the restriction , might want to think about a good single plane if you force feed it in the future. Bit high on the F/P that he was running if it was N/A but a slight correction and you should be good to go.

Also , you can loose the 45 degree oil filter adapter if you want to in your picture , you won't need it and it will make header / manifold fittment easier. Engine was out of a 4X4 I assume ?

Nice truck , wish I would have kept my '79 crew cab Dually , my plan was exactally like yours , TBI BBC / 4L80E , all with a '7427 to control it. Oh , and a blower :innocent2:

TOM

[Randy 79]

If you can use the 7427 with a m/t, shouldn't you be able to do that with the 7060 as well? Just wondering. KS would be nice to keep but not a necessity for me.

As for the trans, this truck will stay m/t, pretty much decided against the 4L80E. I want to get a 4-door truck down the road, just not enough room in the standard cab. So I won't need the DRAC on this truck but I do have it just in case.

As for the cam, PO said it wasn't a dog and matched up well with the 96 Vortec 454 Suburban he replaced it with. The cam is worn so I will be changing it anyways. Block is a 92 and no provisions for roller cam, plain steel timing cover. Just going with flat tappet for now due to costs.

No boost plans, just having fun. The adapter is already off the block (motor was in a 4x4 Suburban).

[Nasty-Z]

Sounds like you have it well in hand then.

Good luck with the project.

TOM

[ony]

I would pick egale marks brain before I started buying stuff, I worked on a hot rod 454 some one changed from a 350 my scanner kept asking for a esc module there was no wires for that sensor or a knock sensor, I sent him to a hotrod shop I put a 8747 an a 7747 with a good bin file in it, still wanted esc an knock sensor. I don't know if they got it fixed or not, I think it needed a wiring hornass out of a 1990 454- std trans.

[EagleMark]

A lot of BB did not come with knock sensor in 7747 but they can be added and bin straightened out.

Swapping to 97427 is same as what you have, no manual bins to start. We've done 97427 with a $0E manual bin and found it's easier and better runner with a $0D auto bin. So I'm going to retract what I first said about a possible ECM swap. Why go to a slower ECM, add wiring for ESC and knock?

That boost cam has backwards split duration steps for boost, can't see it doing anything but hurting performance without boost...

[Randy 79]

Tom, I wish I had it well in hand, I have been confusing myself as much as I am figuring stuff out. I appreciate the help and info I am getting here.

So Mark, are you saying that the 7060 can be used? If I can use it, that's good news.

I will be going with something different than the turbo cam, just to be on the safe side. Are the Comp TBI cams a good choice or is there better choices? Trying to stick with flat tappet to keep costs down. The PO did convert it to adjustable valvetrain thankfully. As for how the turbo cam worked, all info is what the PO told me, I never got to see it run, engine was out of the vehicle already.

[EagleMark]

So Mark, are you saying that the 7060 can be used? If I can use it, that's good news.
I would. May take some tweaking of things for manual, but way better then the swap option.

If you have an available manual bin then it saves some time. Most differences in manual to auto calibrations has to do with Decel, DFCO, IAC. Think about it, how do you drive an auto compared to manual? Most of these tweaks had to do with the deceleration/let off throttle between shifts for emmissions, some are drivability.

But like I said above the guys, myself included ended up with an auto bin in 97427 that was way better then the available manuals... so it can be done. Your PCM is closer to a 97427 then a 7747 or 8747. Actually history wise it was first edition. Had it been in more vehicles it would be just as popular. Very capable. Just can't recall anyone going manual with it. When the 454 came with manual it had the older/slower ECM 7747/8747.

[Randy 79]

Well, about time for an update. I haven't had much time to deal with the EFI swap, too many other things happening. Should be getting the rebuild on the 454 wrapped up here soon. Hope to start the swap probably in November. I am getting a Dell laptop with Window Vista. It was my nieces who got a new laptop. Nice present for me. Now I get to learn all about this EFI stuff.

After doing plenty of research on dual tanks and EFI, I think I am going to have the aux tank feed into the main tank. Seems an easier way than trying to get the selector valve and all the necessary parts together. Unless I happen to luck upon a truck with all the stuff.

Hopefully I will have more updates here soon. Thanks for all the help.

[Randy 79]

Time for a long overdue update. Finally got the engine back in mid-December, a few months later than expected. It is now in the truck at last.
http://i967.photobucket.com/albums/ae160/rjpajer/79%20GMC%20Dually/454intruck_zps08be13d7.jpg

I have the sending units for the tanks (Left side plain, right is TBI sender) and have the pump coming for the TBI. Left tank will be an aux tank and feed into the right tank. I rebuilt the Throttle body with new gaskets and o-rings, it needed it. Also pickup up a replacement distributor as the old one was worn out. Still have a few more pieces to get. I might get lucky on the tuning, the previous owner thinks he has the stock Bin for the truck, he is checking to see. That could help out. Wiring harness is just about done, just need to get the inside connections squared away.

On a side note, sort of an FYI, the 12si 140 amp alternator that was on the truck will bolt in the same place as the 92 CSI 105 amp alternator, with just a little grinding on the bracket in two spots. It at least gives me options.

Some questions I have about it.
1. Fuel lines to the TBI, are the 6AN adapters a good way to go? I will be hooking it to the stock 3/8" fuel line and running a new 5/16" return (it only has a 1/4" return line now). Plan to use adapters to join to the steel line, probably with just a short length of EFI hose.

2. Hot fuel handling module: I don't have the module, just the plug. It looks like there is a power line, ground and line to the pump. Will it work unplugged or do I need to connect any of the three wires together. Hard to tell from the wiring diagram.

3. A/C connection: I have the a/c compressor connector in the EFI harness, can I hook the trucks original wire to that harness, this would be the green wire? Will the computer know then if the a/c is on?

I will probably have more questions as I put it all in. Thanks for the help, Randy

[Randy 79]

Another update. I am just about to the point of getting it running. I got my stuff from Moates (Burn2 and G1 adapter with ZIF socket, HDR1) and was able to download the stock BANF bin. Everything looks good in TunerPro, best I can tell. If anyone could take a look to make sure, since this is my first time.

I also downloaded the BANF-5 bin from the 7060 thread, http://www.gearhead-efi.com/Fuel-Injection/showthread.php?807-16147060-85-Superceeded-to-D8/page2
It sounds like a good tune for what I want to do. Biggest thing I'm not sure about is tweaking/turning off the 4L80E stuff in the bin. I can see it in TunerPro, just need a bit of guidance to get it right. Thanks for all your help.

Edit: I also have a Comp Cams 11-302-4 cam (one of their TBI cams), headers and Edelbrock TBI intake. TBI has an adjustable regulator, was set to 25 psi, I will verify once I get it powered up and can change it if needed. Just in case any of this info is needed for the tune.

[1BadAction]

Another update. I am just about to the point of getting it running. I got my stuff from Moates (Burn2 and G1 adapter with ZIF socket, HDR1) and was able to download the stock BANF bin. Everything looks good in TunerPro, best I can tell. If anyone could take a look to make sure, since this is my first time.

I also downloaded the BANF-5 bin from the 7060 thread, http://www.gearhead-efi.com/Fuel-Injection/showthread.php?807-16147060-85-Superceeded-to-D8/page2
It sounds like a good tune for what I want to do. Biggest thing I'm not sure about is tweaking/turning off the 4L80E stuff in the bin. I can see it in TunerPro, just need a bit of guidance to get it right. Thanks for all your help.

Edit: I also have a Comp Cams 11-302-4 cam (one of their TBI cams), headers and Edelbrock TBI intake. TBI has an adjustable regulator, was set to 25 psi, I will verify once I get it powered up and can change it if needed. Just in case any of this info is needed for the tune.
This should help your 4L80E Tuning. Plug your current numbers in and go from there. the bigger the spread between the gears, the more throttle it takes for a downshift. From my experience with an HD truck and towing, keep them spaced on the wider side or it'll want to downshift too quick.

I will caution you, something is up with the Torque converter lock tuning in the 7060. In my tune it is not commanded to lock in 3rd at any time, yet when I pull the gear selector into third, it's very clear the TCC is locking up. There is also a MPH range that it is going through a lock/unlock hysteresis, which I have not figured out either.

[Randy 79]

Thanks for the info, 1badaction. I actually have a manual trans in my truck (SM465) so I was needing to turn off the 4L80E stuff. I wasn't clear enough in my post, sorry. That's what I get for posting late at night, right before bedtime.

Another question, I have a wire that went to the stoplight switch, originally part of the TCC circuit, any benefit to hooking it up? Otherwise I will just tape it up.
Thanks.

[1BadAction]

Ahh I see. Not sure about the TCC stop circuit. Just out of principal I'd like to know the ECM is getting the "brakes applied" signal, but it may get it from somewhere else, not necessarily that circuit. It would probably run just fine without it, too. With a manual trans you will need to change some of the IAC tables to prevent stalling when coming to a stop for one (Throttle follower, IIRC). Mark has done it in a truck and probably can fill you in better on that subject. The latest XDF I've been working on does have those tables defined, the older one listed here didn't. I still need to get off my ass and finish organizing it, but it does have what you will need.

[Randy 79]

Well, I am quickly figuring out that I have a pretty steep learning curve with this EFI stuff and need some help. I am getting around in TunerPro RT pretty good and would be able to burn a chip for my truck, if I can ever figure out what I am doing with the bin.

I am pretty confused on what I need to do to turn off the 4L80E trans stuff in the bin (I have a manual trans in truck). The .xdf that 1badaction put up has helped a bit (thanks very much for it), but I am not sure what needs to be done. Since there isn't an obvious "off" for the trans stuff, I presume that it involves tweaking the settings. Do they all get tweaked or does just changing a few of them do the trick? Also I'm not sure what IAC tuning is needed as well.

Bad thing is I am in a time crunch and really need to have this beast moving this weekend to get the engine and clutch broken in. I have an event in 3 weeks in which I need it to tow my trailer so I would like a little time to make sure everything is working. If anyone is willing to help out, you can email or pm me on what you need from me. I would greatly appreciate it.

[Randy 79]

Still trying to figure this out auto to manual trans stuff with the 7060. I was shooting ideas back and forth with a friend and he suggested to try deleting the tables for the Auto trans stuff. Sounds like it may be a possibility, as I can redo the chip pretty easily if it doesn't work. But I figured I would run it by the more experienced minds here, so I don't royally mess it up.

Alternatively, could you just blank the tables for the auto stuff? Maybe changing the settings to something that would defeat the auto stuff (for lack of a better term)? I really would like to figure this out, kinda has become a challenge for me to see it work. I am going to download the manual and auto BINs for a 6395, so I can compare the two and see if the differences make any sense to me.

As a fallback plan, I am considering switching to the 6395 pcm, as suggested by Moates. I see there are already manual BINs for it, so that may be a better way. It would take a bit more time with getting the computer, memcal and repinning. But in the long run it may be better. I realize the fuel tables would have to be changed since i have the low-pressure 80 lb injectors. Eventually I will get the hang of this stuff, just may take me a while.

Thanks for all your help and patience.

[EagleMark]

Good idea for the tanks. Running dual EFI tanks requires lots of plumbing. When switch changes tanks supply it must also change return. If you've ever looked at one that came from factory with duel tanks your jaw would drop from all the plumbing/switches/valves... let alone expense!

You already have the 7060 and equiptment to burn chips so go with it. The 7060 never had a manual but I'm sure it could be made to run fine on manual trans. Going to 8747 is a step backwards in ECM/PCM, it's not that great.

[Randy 79]

Ahh I see. Not sure about the TCC stop circuit. Just out of principal I'd like to know the ECM is getting the "brakes applied" signal, but it may get it from somewhere else, not necessarily that circuit. It would probably run just fine without it, too. With a manual trans you will need to change some of the IAC tables to prevent stalling when coming to a stop for one (Throttle follower, IIRC). Mark has done it in a truck and probably can fill you in better on that subject. The latest XDF I've been working on does have those tables defined, the older one listed here didn't. I still need to get off my ass and finish organizing it, but it does have what you will need.

Its been a busy time the past week, so not much done with this. Finally able to get back on it and hopefully get somewhere.

On the IAC adjustments, there are two tables: IAC follower Delay Low VSS and IAC follower Delay High VSS, are these the throttle follower tables? If so the low is set at 400 msec and high is 1000 msec. To prevent stalling when stopping, do you want the delay longer or shorter? My guess is longer on the low VSS table.

With quite a few constants and tables for the transmission, do all of them need to be addressed? The constants seem fairly straight forward, either set them low/high, or out of range so the computer doesn't look for them. May just have to try some settings and see how it goes.

On a side note, I had an autocross event to go to this weekend, so I borrowed my co-drivers truck to pull the trailer. That may have been a "bad" move. It's an 02 Silverado 2500HD with the 8100 and Allison transmission. Pretty amazing combo, especially the transmission. It pulled my trailer with ease, much better than my truck did. I sure hope this 454 pulls the trailer decently, it should at least pull better than the 350 did.

[Roadknee]

On a side note, I had an autocross event to go to this weekend, so I borrowed my co-drivers truck to pull the trailer. That may have been a "bad" move. It's an 02 Silverado 2500HD with the 8100 and Allison transmission. Pretty amazing combo, especially the transmission. It pulled my trailer with ease, much better than my truck did. I sure hope this 454 pulls the trailer decently, it should at least pull better than the 350 did.

I find it wise not to drive that newer nice stuff. I recently borrowed a buddies new Dodge 3500 Quad Cab Long Box Diesel to go pick up a '95 k1500 parts truck I bought. Super quiet, set the cruise control and go. Kinda made me wonder why I'm wrenching on my '95. Oh yeah, it's the $50K or so he paid...

[Randy 79]

Update time. Last night I almost got to the point of trying to start the truck. I hooked up the battery to check everything out and no magic smoke was lost from the harness anywhere, thankfully. Can you tell I also own a British car (75 MGB)?

Fuel system did have two bugs though. One, the fuel pump runs as long as the key is on, it doesn't stop after a few seconds. I don't have a hot start module so that wasn't causing the issue. I have another relay I can try to see if that changes anything. Only other thing I can think of is the oil pressure sender is acting up. Second issue was the fuel pressure, it went right past the 30 psi mark on the gauge around to the stop pin at 0. Unhooked the return line (with the key off of course) and it was dry, no signs of fuel. So off came the TBI to check it for obstructions and to check the regulator (adjustable type). Turns out the previous owner had the regulator turned up most of the way (said it was set at 25 psi), which was blocking off the return. Backed it off quite a bit and put it all back together. Now it holds a nice 20 psi. Glad that was an easy fix, just wish it was adjustable on the vehicle. Something to look into later.

So hopefully tonight I can see if she runs, but I will check everything out again before I try, just to be safe. I also need to get one of the ALDL cables so I can do some datalogging, kinda forgot about that. I am curious to see what transmission codes I get once it is running, cause I am pretty sure I don't have all the trans stuff tuned out yet.

[Randy 79]

It's been a while, ran into an issue while trying to start the truck. It wouldn't fire at all, no fuel out of the injectors either. Luckily it didn't start as I had a bunch of oil coming out of the bellhousing area, around the rear main seal area. So after taking the transmission, clutch and flywheel out, turned out it was an issue with two of the galley plugs at the back of the cam. That took quite a bit of work to get back together, but it is together now.

I did figure out what was wrong with why it wouldn't fire and why the fuel pump just ran. Turned out I had the chip backwards in the ZIF socket in the G1 adapter. I had the chip notch towards the lever, as it is when using the Burn2. Supposed to go the other way, glad I figured it out before I tore back into the wiring harness. I was able to fire the truck up tonight. It started right up and runs pretty darn good and was able to break in the cam. No "check engine" lights yet, will see if any codes show up later. Looking forward to driving this truck, instead of working on it. Thanks everyone for the help.

[Randy 79]

Since I have driven the truck a few times now, a update on how it is doing. Truck runs great, no problems so far with the EFI or the tune (knocking on wood, just in case). The BANF-5 tune that EagleMark did in the 7060 thread really runs good. The engine runs strong and pulls great, runs better than most 454 TBIs I have been around (which isn't too many). It runs fine with the fuel pressure at 20 psi, with the headers and bigger cam it probably needed more psi. I need to get the datalogging going so I can see how it is doing now.

It seems that the 7060 ECU isn't upset about there not being a 4L80E hooked up, no codes or check engine light so far. This is a bit of a surprise as I haven't really turned off much in the bin. I'm happy about that.

The only thing I can see that may need some tweaking is decel, but I expected that. Doesn't do anything funky now, but it probably can use some fine tuning. It doesn't stall when you push the clutch in when shifting or slowing down. A couple times when slowing down in lower gears it started to buck a little, when it got below 1500 rpms. I think it might be coming into a point where the IAC is having an effect. Datalogging may show what is going on here too.

That is all for the moment, I will update as I figure out more on this.

[Roadknee]

A lot of times low rpm part throttle bucking can be fixed with more ignition timing. Some applications can use as much as 50 degrees.

[Randy 79]

Timing may have an effect. Right now the bucking occurs with my foot off the throttle when slowing down. Add a little throttle and it stops. Last night when I drove it, it wasn't bucking at all. Maybe it just needs to be run more.

[Randy 79]

Update time. Truck had a good test this past week, took it out to Lincoln, NE for the Solo Nats, pulling my 28 ft enclosed trailer with the Camaro in it. 2100 mile round trip.

Truck pulled great, had plenty of power and climbed hills without needing to downshift. No check engine lights at all on the trip. Cruising speed was 65-68 mph which was in the 2600-2800 rpm range. Overdrive would be nice to have to lower the engine speed. Coolant temps stayed in check, even with temps in the mid 90s.

It seems the 7060 computer is fairly tolerant of not having a 4L80E hooked up (manual trans in truck), just a VSS from JTR is hooked up. I only had one issue a week before I left, got a code 13 for O2 not responding. Swapped out the heated O2 for a 1-wire O2 (due to time constraints) and all was fine. I guess having the heater on all the time may have been too much for the first O2 sensor. I still have everything there for a heated O2 if I need to go back to one later.

[Randy 79]

Well, this will be the final update to this build. Sold the Dually Saturday (8/1/15), it is in its new home in South Carolina. I did tell the new owner about this site so maybe he will join in. Hope it works out great for him.

I will still be around though, with the new to me '03 Suburban 2500 and my other vehicles, I will still be messing around with EFI stuff.

[1project2many]

Well, this will be the final update to this build. Sold the Dually Saturday (8/1/15), it is in its new home in South Carolina. I did tell the new owner about this site so maybe he will join in. Hope it works out great for him.

I will still be around though, with the new to me '03 Suburban 2500 and my other vehicles, I will still be messing around with EFI stuff.

It sounds like you've had plenty of fun with the truck and I'm glad you found this site helpful. The truck is a great example of an EFI retrofit and I'm sure it will help other people considering the same swap. We can always use OBDII experience so please keep in touch!