Hi all,
2004.5 S40
2.4i
140k miles

I have a huge problem that has been getting progressively worse over the past 6(ish) months. The car will start up fine and idle properly for the first few minutes, but after driving for a few minutes or after warmup, it will idle very rough, eventually to the point of dying.

When driving, if i am cruising and need to let of the gas to stop, it will fall to idle and then when it caches itself to idle, it will die...right in the road....And when i pull in, put it in Park, it will usually die, VS being in Drive.

I have cleaned my injectors, cleaned the air filter, cleaned all electrical connections, cleaned the MAF and connections, cleaned the throttle body. But i am not a volvo expert, im about to take it to the Volvo dealer, but hoping you guys can guide me first.

Thanks for all input.

 

I'd check the fuel pressure while it's acting up.

Any trouble codes stored?

 

No codes, but im probably going to have it looked at by volvo on tuesday. they apparently do a free diagnostic if the check engine light is on. not sure how to check the fuel pressure while its acting up? i dont have guages installed

 

trouble codes = check engine light. If the check engine light is on then you have trouble codes stored. Places like Autozone or Advance can check the trouble codes for free because they want to sell you whatever part you need to fix it.

I asked about the fuel pressure because you have taken care to clean the other problem areas. Hooking up a code reader to see why your check engine light is on will give you a starting place to check further.

 

Sorry for the delay. I got the codes. Over the years there were quite a few, but the main ones are as follows: ECM 250A, ECM 130A, ECM 4201.

Hoping I can figure it out without having to pay the Volvo guys to take all my money!


Thanks in advance!

 

ECM-250A Long-term trim - Upper Limit

The Fault Code ECM-130A is set if the value of the long term AIR trim part load (air mass correction value) and the short term air trim become excessive

P0420/ECM-4201: THREE-WAY CATALYTIC CONVERTER EFFICIENCY

The long term trim upper limit means your car's computer is adding fuel so that your engine does not run lean. Lean/Rich is determined by the top O2 sensor.

The last code means your computer *thinks* the cat is no longer working properly. This might or might not be true as the input is from the bottom O2 sensor.

My question to you: When is the last time you changed both your O2 sensors? They deteriorate over time and should be replaced at least every 100,000 miles.