Okay, Here goes! I am working on a 95 Cavalier 2.2 OHV with OBD1 that has a OBD2 Connector. Car came in the shop Running Rough and Injectors #2 & #4 were Leaking. It had 2 Codes that I pulled that have somehow Disappeared because I didn't erase them.
Code 27 (QDM Fault B)
Code 55 (Lean Fuel Malfunction)
To Start off with the obvious, I replaced all 4 Injectors per customers request. As I had the Injectors out the #2 Injector pigtail was burnt and the Green wire was pinched / about to snap, I replaced the pigtail on #2. Injectors are no longer leaking. I checked Noid on all 4 pigtails and they all blink. The resistance of all 4 new injectors are 12.2 OHM. All 4 Plug wires were Replaced along with the plugs. I have spark on all 4.
To Address the Code 27 (Quad Driver Module Fault B) I checked the Evap Canister Purge Solenoid for Vacuum (it Failed), Tried to Energize it and it did not click. Checked its Resistance and I got 0/L no matter how I held my DVOM. So I replaced the Evap Solenoid. I put vehicle all back together and Still ran rough.
Next I decided to start checking for Broken wires, Grounds, etc. I Couldnt find anything up top, so I moved to the PCM. From there I tested every pinout for voltage and found 2 that were Registering less than 1 Volt. The Evap Canister Purge Solenoid wire (Drk Grn/Wht) and the TCC Solenoid (Tan/Blk). I Checked the Resistance at the TCC Solenoid and it also had a Resistance of 0/L no matter how I tried to test. Checking the wires for those 2 Solenoids both netted under 1 Volt no matter where I probed it at the pcm or at the pigtail's & in between.
I then Installed a new PCM with the old PROM and to no Avail it still is running very rough like there is a misfire somewhere. I even checked the EGR Solenoid and the voltage / resistance was good on both. My only other opinion would be that somehow the TCC Solenoid is Messing with it all. Does anyone have any insight on what could be going on here?
By the way, I have Checked all fuses, ERL & FP Inj fuses are also good, along with relays too.
maybe i missed it but....what was the compression test at? any coolant in the cylinders?
I'm sorry, Forgot to mention that lol.
Cyl #1 135
Cyl #2 125
Cyl#3 135
Cyl#4 135
No coolant in any Cylinders, Oil was fresh and full when it came in. inside Cyl #1 & #4 they were clean as a whistle, #2 looked a little bit dirty as did #3.
Didn't mention this but the fuel filter looked newer, and the lines were redone at one time because they were rusted out (old lines were left on there for some reason).
