What can cause this car to run so poorly all of a sudden, car runs but no power, you must acc very lightly, it will run then it feels like it shifts into fourth gear and it chokes and stalls. This happen when you first start and engine is cold, after it worms up you will be able to start engine but not drive because the condition get worse as soon as you put it in gear it stalls, found 5 codes, PO304,421,431,725,750. Codes PO304 just came up but I dont fell a miss, the other 4 code have been there for 3 years.I know what thay are. If I disconnect the mass air meter flow the car runs even when its hot, Tried 2 new mass air flow meters but still the same. I drove the car about 20 miles in the city on highway and run perty good, but poor accelaration.
P0304: Cylinder #4 misfire
P0421: Bank #1, Right bank, warmup catalyst system efficiency below limit
P0431: Bank #2, Right bank, warmup catalyst system efficiency below limit
P0725: Engine speed input circuit malfunction
P0750: Shift solenoid "A" malfunction
Check the O2 sensor. Run some fuel system cleaner to clean the injectors and valves. Also check for vacuum leaks.
October, 6, 2012 AT 10:06 AM
P0725: Engine speed input circuit malfunction. Sounds like the crank angle sensor