If I catch up and get a log tonight we will see. On the screen? No! It's got some strange values sometimes.
If I catch up and get a log tonight we will see. On the screen? No! It's got some strange values sometimes.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
i would probably keep moving the crank sensor further away from the trigger wheel they false trigger easy.when you get to the point it just cranks and wont fire go a tad closer LOL.you also may need to filter the input to the icm like such this was for a different module but help with random rpm spikes in logs from false triggers
We have a winner on the timing! delcowizzid!
I loaderd up some spacers and got no fire and took them out until spark returned. Now the timing on 2-3 is 180* out and 1-4 is correct. With bypass connected the timing looks to be responding to RPM properly. Runs much better... except idle.
Still have an idle issue and can't find a vacuum leak. Even blocked off IAC and anything to get less air, still only idle very high.
Attached is a data log in case anyone can find an issue I can't. IAC counts are 0 due to block and ocasional IAC error 35, part of log may have error 42 when bypass dissconnected. Other parts of log have no errors.
Also attached an $8D log but nothing on it looks right?
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
lower tps voltage under 0.5 looks like its not in idle mode unless its closed loop idle.targeting 14.1 ratio ide have it idling at 13:1 open loop at least for a start bpw is bouncing a lot and so is the rpm and airflow at the same time as the o2 swings trying to maintain a/f ratio.2 degrees of timing is that offset in the tune for 20 degree base advance on the crank sensor?.
also some big rpm spikes in there still trigger issues
Just had time to look at that log and first time I noticed the RPM spikes! Obviously it is not accurate and a spike. The other idle RPM seems accurate/horrible and other data matches it happening. You think this is a crank trigger issue? It seems the spike coincides with the engine trying to stall while OL...
Here is the other data log which is longer I wanted to post. It has a dead spot at about 3:48 where I cleared the error 42 and re connected Bypass. There are some rev ups in this and you can see them in TPS, some are to keep running until CL where it seems to at least stay at the horrible idle.
Looking at it now but I'm not sure it would show anything more then the first short one...
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
big rpm spikes in that log too.the sensor bracket needs to be bloody solid weve had a couple of people on our forum with resonance through the block vibrating the sensor making spikes and unclean rpm signals.
1/4 inch steel?
I'm about ready to ditch the crank sensor and DIS and put a distributor back in. Not sure where that would leave me for a bin and definition? That just adds more time to this project I don't have. Actually when I started time was all I had... even then I may still have a vacuum leak or mechaincal issue as this should be idling better?
But I'm running out of time chasing this and have to have it running before I go to surgery the 15th. It get's every spare minute I have! Got way to much time into it already and wanted to do some spring crappie fishing before the hospital and maybe a little life too! Might be half a summer before I recoup...
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
If the trigger wheel's not drilled in center could do it also. Or where it's mounted on balancer could do it, too. I machined mine bolted to a balancer and pulleys and used the same balancer and pulleys on the engine. I indexed the pulleys and balancer so it will always go together the same way. There's no guarantee a stamped pulley is flat or straight. Dial indicator on wheel is how I'd check for running true.
If putting in dizzy, use cal with distributor limits. Say 6 deg reference angle, max advance 75 deg, max retard -10 deg. All else should be same.
This trigger wheel is mounted to a spacer bolted to balancer through the pulleys and is less then .020 out if checked in four spots around the wheel. IIRC the air gap had a bigger tolerance.
I got some valve spring spacers from the engine builder machine shop that fit the crank sensor. They measure .030 and I stacked two and lost all spark, with one I get correct spark on 1-4 and 2-3. With no spacer the timing light fires all cylinders at same spot.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
also the slots need to be as wide as the sensor tip and the sensor needs to be at a right angle to the wheel if its leaning into or away from the rotation of the wheel they do weird things.i noticed your bracket for the sensor is quite long maybe weld another peice of flat bar on the back on its side as a brace so it looks like a bit of angle iron
Dam! I knew when I quit drinking in 1986 it was going to have adverse effects!!!
We are tinkering with it now so I'll give that a shot.
Slot is approximately twice as big as sensor tip. Sensor is square to trigger wheel. Picture is old but yes it could be considered long, it now has a bend in middle so more sturdy then just straight the entire length. I'll have the kid tack on a flat piece at 90* as a brace to check that as well.
Also received a Memcal today from 1project2many (Thanks You! ) so going to try that as well. Even though the error 41 has not been an issue since I soldered in resisters.
Since it seems you have plenty experiance with trigger wheels... have you had any issues with the Shield wire? Mine comes from the ICM but is only about 6 inches into harness leading to crank sensor. The other two wires to crank sensor are a twisted pair and covered in plastic convoluted tubing all by themselves, they do not share any space with any other wire. There is absolutely no high voltage wires anywhere near it. The closest place the wires to crank sensor are to high voltage is at the plug to ICM and spark plug wires come off coil mounted to ICM, this is where the shielded wire extends from plug into harness.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
try this for shits and giggles cut and paste from our aussie delco master vl400 reguarding sensor polarity :D maybe you need to reverse the crank sensor wires
You can use a multimeter to work it out but you also do need to find out if the DIS module needs a rising and then falling or a falling and then rising signal.
To find out the polarity connect the sensor wires up to a multimeter. Get a screwdriver and place it on the sensor tip, as you remove it see what the meter reads. If you see a negative voltage then the lead connected to the positive of the meter will be the positive signal wire when using a toothed wheel and rising then falling signal. Swap the polarity for a slotted trigger wheel.
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