My $59 problems/tuning a turbo camaro

[EagleMark]

Did you pop something loose on boost side?

[fasteddi]

Its the freaking fuel pump. No pressure at all and yes it has enough gas in it. I can actually push the shrader valve and after I purge the car, and barly anything comes out, and thats with the fuel rail out so I can see if the injectors purge.

The injectors ohmed out at 15.4 ohms@75 degree temps, all of them.

So not its on to a better fuel pump I guess.

I can even push in on the hose from the tank to the fuel rail. So little pressure that its easy to push in(soft)

[RobertISaar]

well, the good news is that you let off on it as soon as it happened, so little chance of engine damage.

Walbro 255 or higher, IMO, depending on just how far you're trying to go.

[fasteddi]

Its just a drop in replacement so I dont need a diffent sending unit, "I think" I am looking at the walbro 255 to replace the one thats busted.

[EagleMark]

Is that enough to add nitrous?

[fasteddi]

no n20 but enough to make sure im getting the right fuel pressure and can go back to running 12psi

[fasteddi]

Got the walbro 255 pump in and were good to go, but now RPM's higher then 4k are just stinkin rich 10's and very low 11's AFR. Sad face here, now I have to tune for another ungodly amount of hours to get it right again.

[EagleMark]

So that whole time you were running out of fuel above 4k... that's why you thought it was low on power up there! Wait till you get it right now with enough fuel!

[RobertISaar]

Got the walbro 255 pump in and were good to go, but now RPM's higher then 4k are just stinkin rich 10's and very low 11's AFR. Sad face here, now I have to tune for another ungodly amount of hours to get it right again.

well, the good news is as Mark stated, now that you can actually deliver the fuel the engine wants, MOAR POWER.

also, your injector PW will obviously drop quite a bit to get the AFRs where you want them. because of that, your max recorded DC will drop as well, so you'll actually have more room with the injectors you have now.

[Six_Shooter]

I ran into something similar on a friend's car this weekend.

He used to have a Camaro in tank pump and some Ford external pump running to his custom 4bbl TBI. Over the last few weeks he installed an Aeromotive AFPR, along with the new 4bbl TBI, and an Aeromotive fuel pump, in the tank, and removed the other two fuel pumps. I tuned it a bit last year, but could never seem to get the fueling just right, sometimes it would be rich, other times lean, and sometimes when you held your tongue just right as you mashed the pedal it would be fine. VE tables in the upper RPMs and load were in the 90s previously. Started taking fuel out in small increments, over and over again, until finally I just too a bunch out in those cells, and BAM, almost perfect AFRs under load and RPM, and boy did it pull hard, never felt that heavy slug move that fast, ever before.

I'm not saying to just pull a bunch of fuel all at once, but you may need to remove a little more than you think you do, just to see a change.

[fasteddi]

I plan to get a few min tonight to tune, Yea the car is so freaking slow at those Higher Rpms with that rich condition.

@sixshooter, yea I have no idea how much fuel to take out in some cells as its was reading 10.1 and thats the bottom of the window so who knows if it is 10.1 there or 9.7. But ill go at it and take some fuel out in increments and hopefuly I get some results sonner then later. But thats the way tuning goes.

[fasteddi]

Im tuning at the moment but have a question, car is having hard starts when warm, is that from too much timing when its cranking over?? Its was 20* then I droped it to 18* and still seems the same.
Thanks!!

[fasteddi]

Nevermind, I actually added a bit and it starts better. 23* total in my lowest rpm cell on my SA table(which is the Idle table)

[fasteddi]

Nevermind, I actually added a bit and it starts better. 23* total in my lowest rpm cell on my SA table(which is the Idle table)

Well the car started well with the added timing because it cooled down..so im back to square one on the hard start when the car is warm


Tommrow Ill go and take a crap load of timing out and get it to arround 14* or so and see if that helps.

@ sixshooter if you see this post, my lowest Rpm line is 600Rpms in the F1 table, IIRC you said to use the 400Rpm one, so since my 600Rpm row is the lowest thats the one to use correct?? Thanks again

If that doesnt help the situation does anyone have any ideas?? Car start really fast when cold but after a nice long datalogg its hard to start but still starts and runs fine, it just takes longer to initially start.


I got up to about 13psi of boost today and was scared to go WOT since I saw some KR, so tommrow I might get some time to further tune. Damn boost is addictive!! And with that new fuel pump im only pulling 70-75% DC on the injectors now!!

[EagleMark]

Is it like stopping the motor when turning over? Like to much timing? Or weak battery? Or are fuel lines getting hot with new plumbing?