1997 Pontiac Grand Am Quad Driver And Oxygen Sensor Codes

If I put my 1997 Pontiac grand Am shifts into gear too soon after starting it, it sets a check engine light and i get the trouble code 26 -Quad Driver. I had the PCM replaced because of other problems that I still having. Car will not accelerate in reverse, gets bad gas mileage, has DTC 13,  goes slow climbing hills, and poor acceleration from a stop. I have already changed the oxygen sensor, spark plugs and wire boots.

DTC 13 is being set either because the catalytic converter that was cut out by the last owner, or from the leak where my exhaust pipes connects just before the muffler? Could those things also affect the  poor performance of my Pontiac?

I just noticed my converter has been cut off and i will have a new one put on soon.

Yes, that could be the reason, or might be others. It may also be contributing to your acceleration problems, but probably not the stalling condition. You might have a leaking fuel ressure regulator. That can be related to the Quad Driver code. There are several quad drivers inside the computer, each of them control four different things. It could be anything from a bad EVAP purge solenoid to a transmission  solenoid.

Thanks for your response, I’ve got some new information on it. Today while I was driving, the car wouldn’t shift gears at about 40 mph, so i let off on the gas a little hoping it would shift. When I returned to push the gas pedal it acted like it was in neutral gear. After abou 10 minute it re-engaged.

After researching this new symptom, we found the problem with code 26 is probably a Torque Converter Clutch Solenoid, which would cause the lack of power, poor gas mileage, DTC code 26 and dying out. When we come to stop sign it acts like it wants to stall sometimes. I have to pop it in neutral to keep it running.

So looks like this could be the problem, problem is I have no knowledge on this subject. If this sounds like it could be the correct diagnosis, could you share some insight on the TCC, anything will help. Where is the solenoid? How do I test it? How do I replace it if necessary? Where’s the wiring, so I can check the ground and such?

Yes, the TCC could be some of your problems. It is also a good idea to replace the 2nd and 3rd gear switches. Thes are located inside the side coder of the transmission. The side is remved by taking off the shift lonkage bracket from under the hood. Then remove the uper side cover bolts. Now go through the drivers side wheel well and remove the inner splash shied, thenthe rest of the side cover bolts. Depending on your model, there may be a large mountand bracket in the way. If so, this would have to come off. This requires supporting the engine and trans. from above, then lowering the driver side of the frame in order to get the mount and bracket off.
The TTC soleoind comes with its harnes, the other 2 switches do not. They just screw into the valvebody.

I know you can test the coil pack, coil housing, and cover on my 2.3 quad 4 with a voltmeter. The thing I forgot is how to test them and what the readings should be. Is there anyway you have this information.

Thank you. When I changed the plugs I noticed discoloring of the housing. Maybe this is causing some of my problems?

Muffler Install On Pipe

Is it safe to connect the muffler straight to the header pipe for the time being until I can afford to actually fix it properly. Secondly, will doing this quit down the car enough for it to be drive somewhat legally and less noticeably. The exhaust pipe broke at the flex pipe that connected to the catalytic converter and it’s been super loud every since and hasn’t been able to be driven because of that.