Check engine light came on...HELP!!!

[sjcruiser]

Hi guys,

I'll loan a ODBII code reader soon to read the fault code...Meanwhile, here're what I have done to the truck in the last few days - dont know if it's a coincidence or not:

. OME851/860 springs installed (upgraded from OME861/862) with new Bilstein shock absorbers - I did not encounter anything unusual when swapping out the springs; this was about a hundred (100) miles before the CE light came on.

. The original Panasonic battery went dead after almost 8 years - had known it was coming (showing signs the week before) but I gamed instead - new Interstate MTP-24F battery installed 50 miles ago.

. New Bridgestone LT285/75/R16 AT Revos installed 30 miles ago.

Anything I should check in the mean time? The truck runs and drives fine regarless.

Inputs are greatly appreciated!

Thanks in advance,
Frank.

 

[C6H12O6]

You need to pull that code ASAFP to know what's up. Anything else is just a guess. If you don't have a reader, stop by an Autozone store tomorrow. They'll pull the code for free, then post up the code here or do a search for more info. You can pull the EFI fuse after they run the code to clear the light. If it comes back right away, I'd go through the test procedures in the FSM (you have one?) right away. If the light doesn't come back, you might be fine to just keep driving it indefinitely.

 

[sjcruiser]

ODBII codes:

P0172 - System Too Rich (Bank 1)
P0172 Pd - System Too Rich (Bank 1)

Not sure if the two codes are the same or not. I'll hunt for more info.; meanwhile, any inputs are appreciated!

Cheers,
Frank.

 

[sjcruiser]

Found RavenTai's post:

===========================================
P0172
When air fuel ratio feedback is stable after engine warming up,
fuel trim is considerably in error on LEAN side.
(2 trip detection logic)

Heated oxygen sensor (bank 1 sensor 1) malfunction

Mass air flow meter

Engine coolant temp. sensor
<SNIP>
INSPECTION PROCEDURE
1 Check air induction system (See page DI–21).
===========================================

Checked the Fram ;p air filter, seems like it needs replacement :whoops: - I put it in as an interim filter till I could get an OEM one but my messy records shows that it's been there for more than two years

The CE light actually went off by itself while my wife was driving it yesterday (no, the bulb's not burned ). I'll reset the code once I get the new filter from Dan - we'll see if returns.


Frank

 

[OGBeno]

I created an entire list of possible codes here:

https://forum.ih8mud.com/showthread.php?t=104399

(I assume only relevant for 95-97)

 

[sjcruiser]

Update:
=====

It's been 5000+ miles and the CEL hasn't come back with new OEM air filter installed.

I guess the light was triggered by a restricted air flow from a semi-clogged Fram filter.

 

[Scamper]

I'd bet that your CEL was due to the battery replacement. When you remove the battery, the ECU is cleared, requiring it to relearn the proper fuel trim settings. It may have simply been running rich for a couple of trips before settling in on it's settings. To be safe, I'd get it checked for pending codes if you can, but it's probably okay.