Engine Troubles

[Melhoffman]

Alright here are the codes that I have currently on my 2000 Grand Am SE with the 3.4L V6: P0122 (Throttle/ Pedal Position Sensor/ Switch A Circuit Low Input), P0305 (Cylinder 5 Misfire Detected), P0405 (Exhaust Gas Recirculation Sensor "A" Circuit Low), P0442 (Evaporative Emission Control System Leak Detected (small leak)), and there was another code that was pending when i parked it. It said that the cam position sensor was low circuit or that it was off, i dont remember what it said. This last July i bought the car and it had a blown head gasket and i fixed that and it was fine up until the end of last month. These codes were there for awhile but it wasnt running bad so i left it alone. One day into work it started running horribly, i.e. going up a small hill at 50mph it had to down shift and rev up to 4000 just to not lose any speed, i generally go up that hill at that speed doing 1700 rpm. It starts fine but while running it sounds like it back fires and it idles high as well. It will idle at 1100 and when it sounds like it back fires the engine almost dies. It made a knocking noise for awhile (like a month, coming and going) before it gave out on the way to work. Hopefully this is enough information to solve my problem.
Thanks
Chris

 

[melsg5]

each one of these codes has multiple causes. The most likely cause for your current problem is the P0122, unless the code you didnt list has similar symptoms.

http://www.obd-codes.com/p0122
http://www.obd-codes.com/p0405
http://www.obd-codes.com/p0442

 

[Melhoffman]

I have replaced the throttle position sensor and the car still runs like shit. I did not drive it because of this. The exhaust smelt heavy of unburnt fuel, i dont know if this might help. What would the next thing inline be to test?

 

[Zimgxp]

Start with the lowest number code and work your way up. Check the wiring associated with the tps.If it was knocking, there may be mechanical damage also.

______________________________

 

[Melhoffman]

So for the next code in line that would be P0305 (cylinder 5 misfire) how would i go about figuring out what is causing that. The guys at work say that it could be a burnt valve or a bad ignition coil. What do i do.
Chris

 

[melsg5]

attached is the list of causes, the P0405 could cause the P0305 if the EGR problem is effecting the mixture in cylinder 5.

http://www.obd-codes.com/p0305