Hello, I am kind of new here. Looked through the pinned notes but did not see anything that fits my situation. My car runs well on highway but when running in stop and go traffic will die if in drive. I took it into the shop and the mechanic says he cant figure out the trouble (affordably) as I cant afford to drop 400+ bucks just to figure this out. He did say the injectors are not firing right they actually pulse rapidly, he told me it runs bad because its dumping way too much fuel, but supposedly all the sensors (MAF,o2, etc) seem to be ok. He said he thinks it maybe the "computer". I am not even sure if this has a computer. I do know its a Boshe 2.4. Does anyone have any suggestions? While I did get a good deal on the car I am not really able to drive it as its too unreliable at this point... Thanks in advance if anyone might be able to suggest where to go from here

 

The computer theory is plausible. I'd idle it and kill it then immediately pull the spark plugs. If one or two are soaked in gas I'd suspect a leaking injector for that cylinder(s). If all were, it's overfueling due to a sensor issue. Also look at the vacuum line from the fuel pressure regulator to see if it's full of gas; they can occasionally rupture their internal diaphragms and wreak all kind of havoc.

My experience is these cars want to run lean: a vacuum leak after the MAF runs lean, a dirty MAF runs lean. A bad coolant sensor might run rich. Going to have to do some diagnostics I guess.

 

Thanks will start there. Appreciate your time and suggestion(s). Will update when I've checked that stuff!

 

The computer, to me, would sound like the problem. My 740 sedan would not start a few years ago, when it was not running for about 6 years, and it was replaced and it started just fine, until I ran out of gas. But if the mechanic said that the injectors are putting too much fuel into the cylinders, then that might be the main culprit. Might also want to check the relays.

 

I think I would start by checking the codes. Beginning in 89, OBD is present. Check the codes. If you don't know how, let us know. The pink label ecu in 89 is trouble prone, but there are all sorts of other, relatively minor issues to address first. Could be as simple as the speed signal from the rear sensor isn't making it from the speedo to the ecu. Could be a bad O2 sensor. Honestly, I would wager there are a couple/three things that are all not quite right. Combined, they equal a crappy run condition. Oh...I'd consider a different mechanic unless you are in a rural area and do not have much choice. LH2.4 is child's play to diagnose when you see it often.

 

Check the fuel pressure regulator pull the vacuum if there s gas its bad. It's leaking gas back into the manifold bad gas mileage/idle issues

 

I finally got the Bentley Book and check codes... only one there reset the ecu drove for about 30 miles, trouble came back. Checked codes again... same 1 its : 2-3-1 which says fuel system compensating for rich or lean air/fuel mixture at cruise. The check engine light came on again and the car will not hold an idle after the drive. It ran during drive between 15-70 miles per hour, not stall or hesitations. Not sure if anyone else has seen this. I am going to get a full tune up this weekend but I dont think thats the issue.

 

2-3-1 could be a fouled o2 sensor, a funky MAF, air leaks in the intake or exhaust manifolds or air plumbing or vacuum lines, bad fuel pressure.

 

Check your throttle position switch. If it isn't adjusted correctly, especially if your speedo doesn't work, the car won't idle after highway speeds because the ecu gets no signal that you're idling. LH won't work well w/o a properly functioning O2 sensor, so if it checks out marginal or worse, I'd toss it.