alright, scanned my car today and got 4 codes
1st code : code 27- EGR electrical fault(QDM) :no duh, its not on there, but is this the quad driver problem?

2nd code: code 26 - Quad Driver Module 1 fault- how do i fix this? what is it?

3rd : code 67 - A/C pressure sensor falt - not sure how to fix this

4th - code 77 - fan 1 fault

the 1st, and 3rd codes have came up before, and do not really affect anything
for the past month or so, ive had this crummy back-fire/miss at low RPMs, today it stopped, and miraculously, the SES light came on, which is why i scanned it. Now, the backfire seems to be from the 2nd code ( code 26) My boss said he wasn't sure what its caused from, but he thinks its either in the computer, or the ignition control module?

Injuneer, shoebox, need ur help on this one guys

 

You're using the wrong code list. 1993 was the last year that used a "quad driver module". Use Shoebox's list.

http://shbox.com/1/Dtcs.htm

DTC 27 = Exhaust Gas Recirculation (EGR) vacuum control signal solenoid valve circuit = burned out solenoid, blown fuse, loose harness connector, bad wire

DTC 26 = Evaporative Emission (EVAP) canister purge solenoid valve circuit = burned out solenoid, blown fuse, loose harness connector, bad wire

DTC 67 = A/C refrigerant pressure sensor circuit (pressure sensor or A/C clutch circuit problem)

DTC 77 = Cooling fan relay control circuit = burned out relay, blown fuse, loose harness connector, bad wire

 

okay, i was using a snapon solus and thats just what it told me lol
anyways, could the code 26 and code 27 be because i did my headers, and removed the EGR and dont have it tuned out yet?

 

It might explain the EGR code, but not the EVAP one.

 

well, the car has 150k on it, so its possible that the evap is clogged or something

any idea on the fan and the a/c? wheres the most logical place for a loose wire for those?
or which fuse? they all say it can be a loose wire, or blown fuse, im thinking one of those 2

 

Can also be caused by cracked, deteriorated, broken or loose hoses to these.

 

well, the EGR is not even hooked up lol, so i know thats why that code is there

as for evap - not entirely sure, that just showed up today, and i cleared the code, and it came back

i cleared all the codes, and the only ones that came back were the evap, and the EGR.
I can just get these tuned out, correct?

 

It has NOTHING to do with whether the EGR valve is hooked up, and it has NOTHING to do with whether there are cracks in the hoses. These are ELECTRICAL fault codes. They are determined by the PCM looking at the voltage in the circuits.

If you removed the EGR valve, did you also remove the EGR vacuum solenoid? If so, DTC 27 sets because there is an incomplete electrical circuit due to the missing solenoid. Measure the resistance of the EGR vacuum solenoid, and put a resistor of the same value in the harness connector.

The EVAP purge solenoid and EGR vacuum solenoid are both supplied by the same fuse. A blown fuse would cause both codes. In the 95's the same fuse supplies the fan relay. Now we have explained away three codes. But you have to take the time to check the fuse, look at the connectors, check the wires, etc. If you don't take the time to follow up on the suggestions, it isn't going to fix itself.

 

do you know what fuse it is? Is it inside the car, or (im assuming) under the hood?

 

Right now, I only have access to Shoebox's 95 diagrams. In the 95, its fuse #6 in the box under the hood. Not sure about the 94, but it lists what is on each fuse in the Owner's Manual. If you don't have a manual, Shoebox has a link to each year's manual on his website.

 

kk, unplugged the fuse, it was blown
put in a new fuse
code gone
thanks injunner - you are the man

 

alright, today, started the car, codes showed back up again
with the new fuse when the codes werent there

replaced the fuse again, and tried listening to anything that sounded unusual when i notice
- hey, my fan turns on as soon as i turn the car on
so i'm thinking that's my short, but just to make sure - the fan isnt supposed to turn on right when u turn the car on, correct?

 

The fans will come on all the time with some codes. Typical is DTC 29 for the AIR pump = fans run all the time. Probably any code related to high engine temps, like a failed EGR circuit, can cause the fans to run all the time.

 

alright, i unhooked my AIR pump, and the code is gone, but my miss is back