Volvo 240 Wagon: Stalling/chugging engine

Guest · Post by **Guest** » 07 Jul 2005, 15:39

My engine was chugging this weekend.. as if RPMs were jumping down for a bit and then back up to normal running range and eventually stalled. Would stall if I just let it run and when I give it gas...

Dropped it off at the Shop today and they can't do anything for me [they don't do foriegn cars

] but said the computer scan said the Oxygen sensor was bad and also said that wouldn't cause it to stall..

Any ideas? Catalytic converter? Anyone experience similar problems?

adrianpike · Post by **adrianpike** » 07 Jul 2005, 17:56

It sounds like you've got a signifigant fault in your fuel injection.
Year of car would help a ton.

O2 sensor shouldn't be enough to cause it to run *that* out of stoich, but it's a start. I would at least pull it, if my gut feeling is correct, it'll be nice and blackened by soot, it sounds to me like you're running really rich.
Check your plugs too, they'll give a clue as to whether I'm right.

Once I know the year of your car, I'll do my best to help out further.

Guest · Post by **Guest** » 08 Jul 2005, 09:43

Ohh totaly forgot that part.. it's a 1993 volvo 240 wagon. The woman at the dealership said a bad O2 sensor would make the catalytic converter run rich, etc. Fuel injection is kind o fmy thought as well after running through this websites archives, etc.

Thanks for the help

Hannah

Guest · Post by **Guest** » 12 Jul 2005, 20:09

I have a similar problem. I just picked up a 1990 240DL 4-door with 93000 miles. The car has always been serviced at the Volvo dealership, down to the Volvo plugs, wires and such. The timing belt was last replaced at 68000 miles.

Now to the problem at hand. The plugs are very black and smell of gasoline. The motor mounts are broken and the engine runs rough and has a problem idling. I don't know when the o2 sensor was last(ever) changed. The check engine light is on. How can I get the check light to 'flash' codes for me? What codes might signify the o2 sensor being bad?

Thank you

240dl90 · Post by **240dl90** » 06 Aug 2005, 13:06

ok I did the search and followed the leads it provided. I am the 'guest' above. I have since replaced the cap, rotor, plugs and air filter. no help. I checked vacuum lines and cleaned all gorunds. While the engine was running, I removed one of the two ground wires near the injector rail and the engine stalled. I added another ground wire from the battery post to this connection. no help. I cleaned the throttle body(took it off) and the amm. no help. I put on another amm from the junk yard(50.00) and it was no better. I took the volt readings on all 5 wires of it and the original and they were the same. I returned the junk yard amm and got my 50.00 back. I still don't know if it is bad. At first I was getting codes that indicated the amm might be bad. But after unhooking the battery(to clean the posts), I have no cel. I have 'driven' it about 10 miles(chugging and stumbling all the way) and still no light. When I disconnect the o2 sensor the engine stalls, so I am assuming(I know) that the o2 sensor is working. Anyone have any ideas or known good o2 sensor or amm they want to 'loan' me. I don't mind replacing these items, but they are expensive, if I knew that would fix it. Hell, if money was no problem, I guess I would just drop it at the shop and say 'fix it'. HELP Please

240dl90 · Post by **240dl90** » 11 Oct 2005, 18:09

O.K., I have since replaced both (as long as I had the intake off) of the coolant sensors and the car runs the same. I have had two 'good' amm's on the car and it runs the same. The only improvement so far is the exhaust smells normal (not like straight gas) and the plugs look good as well. The engine still stumbles and the car has no power if I try to drive it. The car starts right up, but wants to stall sometimes. Anyone have any ideas?

Guest · Post by **Guest** » 15 Oct 2005, 10:07

there isn't much left. I would check the fuel pressure. Sometimes the fuel pressure regulators go bad. If that is ok I would unplug the MAF this puts the fuel injection in limp home mode. It will not run great like this but if it runs better I would suspect the air flow meter (MAF) If it dies at a particular throttle setting (a dead spot in one place) then you get to buy a throttle position sensor. Plese let us know what you find.