ecm error??

[KReePiN]

on my 89 silverado.....5.7 tbi.....i threw my scanner on it just for the heck of it.....i dont have a check engine light.....and my truck runs great....however my scanner brought up a code 55 for a ecm error.....anybody know what would be causing this?

 

[96Z71ECSB]

Check the ECM grounds. Make sure they are clean and tight.
They are usually attached to the thermostat housing bolts.
After cleaning or tightening the grounds, clear the code, drive, and see if it comes back.
If it does come back, time for a new/used ECM.

 

[KReePiN]

its weird cause my code reader is also saying i have low tps voltage....my egr is out of position.....and my maf sensor has low voltage also.....all these parts have been replaced so i dont really know whats wrong......yet my truck runs great and i have no check engine light......would a injector pod spacer throw everything out of whack like that? cause thats the only aftermarket item ive installed

 

[great white]

Dump the scanner. They're not required on OBDI trucks. All they are doing is jumping pins A+B on the DLC, but they have been known to "cross talk" on the datalink and frigging things up.

Jump the AB pins with a jumper wire (paperclip works well) and see if the codes are the same.

If they are there, clear them and check again after a drive.

If they return, check the grounds as recommended. You may have a dodgy one and is causing transient error codes. These are stored as history codes in the ECM and are not active faults.

Bad grounds cause all manner of bizarre issues on EFI vehicles....

 

[KReePiN]

thanks alot....my primary concern is whether or not i will be able to pass smog inspection in a couple months......soft codes wont fail you right? its mainly the hard ones that cause a cel light to come on that will fail you right?

 

[95Escahoe]

thanks alot....my primary concern is whether or not i will be able to pass smog inspection in a couple months......soft codes wont fail you right? its mainly the hard ones that cause a cel light to come on that will fail you right?

Aslong as there's no cel on you should be good

Sent from my HTC One X using Tapatalk 2

 

[great white]

thanks alot....my primary concern is whether or not i will be able to pass smog inspection in a couple months......soft codes wont fail you right? its mainly the hard ones that cause a cel light to come on that will fail you right?

Don't know, you "California boys" have some pretty funny ideas on emissions controls....

Aslong as there's no cel on you should be good

Sent from my HTC One X using Tapatalk 2

IIRC, they hook up to the ALDL and scan the computer for codes. Any active ones and you`re pooched. Some error codes can set, but not illuminate the dash light.

I do believe they also look at stuff like vin to make sure it matches the vehicle. Has to do with the proper calibration for the year IIRC.

Don`t quote me on any of that though, I don't have to deal with California laws....

 

[KReePiN]

ahhh ok...i guess we will see what happens lol!

 

[DR CHOP]

Don't know, you "California boys" have some pretty funny ideas on emissions controls....



IIRC, they hook up to the ALDL and scan the computer for codes. Any active ones and you`re pooched. Some error codes can set, but not illuminate the dash light.

I do believe they also look at stuff like vin to make sure it matches the vehicle. Has to do with the proper calibration for the year IIRC.

Don`t quote me on any of that though, I don't have to deal with California laws....

They usually dont hook up on obd1 for smog. Just got my 93 done ( finally passed)

 

[DR CHOP]

its weird cause my code reader is also saying i have low tps voltage....my egr is out of position.....and my maf sensor has low voltage also.....all these parts have been replaced so i dont really know whats wrong......yet my truck runs great and i have no check engine light......would a injector pod spacer throw everything out of whack like that? cause thats the only aftermarket item ive installed

Did you unplug battery for a few minutes to reset ?