I also cant get any change in rpms by turning the dizzy it just kills the motor. Thanks all for input
I also cant get any change in rpms by turning the dizzy it just kills the motor. Thanks all for input
Gentleman, We were finally able to get error codes from the service engine light bulb that we added to the harness. When connecting a 12 pin connector and attempting to get obd1 info, the obd1 reader will not communicate with the ecm. Does anybody know if there are any additional wires to hookup? we have been using the wiring diagrams from www.gearhead-efi.com/Fuel-Injection/showthread.php?304-1227747-ECM-Information-42 for this. We want to be using the aldl but cannot get communication and everything looks like is hooked up correctly and like I said, we can at least get error codes. Does it still have to be jumpered from A and B when using an obd1 code reader?
RIght, and you won't because the RPM is computor controlled, not mechanically controlled.Originally Posted by tra1nwreckage
No jumpers for ALDL data or when hooked up to scanner.
Getting flashing code 12 and nothing else is good! No codes. I've seen many scanners not show data when it comes to OBDI. All you need on ALDL port is A, B and E. Some old scanners need cig lighter power.
Re-reading your thread it does seem like you have a bad EGR, block it off. Still need a chip with EGR turned off for fueling and spark to be correct. With no knock sensor your knock counts keep counting so knock retard is in full force. Still need a chip with knock removed for correct spark advance.
What is fuel pressure?
Have you set timing to 0 with bypass wire dis-connected? Then connect, clear codes and re=start.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
That makes sense about the dist. So unplug dist. From harness set motor to 0 on timing mark and plug it back in? Also do you have a link to a bin deleting the knock sensor i would appreciate it. The egr is working properly, i found out the diaphram holds vacuume when squished and plug the hole with a finger. Thanks for all your help eagle mark
Oh yeah and i get a code 12 when key is turned to "on" position and when i start the motor it flashes constantly with no gaps..... any ideas?
Flashing CEL is major failure!
Or is this happening with A and B paperclip? Not really sure what happens if you try to run with A and B crossed? Not supposed to do that, it's a Key On Engine Off trick.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
We did run the motor with the paper clip jumped from a to b. We didnt get any difference with the ecm or motor but i will take it out next time we try. Also did you know of a BIN that removes the knock sensor?
Pretty sure all the 5.7L had knock... why would you want to take out a good sensor?
Do you have VSS? It's also a good thing for Rock Crawlers as it stabilises Idle, ECM likes to know if it's moving or not. Can be turned off though. EGR? Really not needed for the rock crawler.
You are really going to need a custom chip, just the added spark advance is worth the chip for your situation. If you ever find the issue.
Why don't you re-cap, where are we and what is issues right now?
Have you set timing with bypass disconnected? Fuel pressure? These are 2 major things the ECM has no way of knowing are not correct.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
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