To all,

I fixed the mysterious 10 gallon tank problem by properly positioning the sending unit in the tank and then the car started shutting off. Actually, I do now remember it doing once before I fixed the tank problem so I don't think it was anything I did. I was under the hood and checking the tranny fluid when I first bought it a couple of weeks ago and the engine acted like it momentarily shut off and then continued to run. I asked my wife who was sitting in the car at the time what she did and of course she said "nothing". Since then it has been occasionally "stumbling" while driving down the road and sometimes shutting off when stopped and idleing. It always starts again right away. I brought it to a local imported car repair place and they replaced the Idle Control Valve @ $250 parts and $30 labor. Now the car is still doing it. I am going to call them today and see what they say but I wanted to check with you all for help first. This isn't costing me $280 and you all have more collective experience. Of course intermittant problems are the worst, hard to tell right away if the problem is fixed. Any help is greatly appreciated. It is a 1990 740 2.3L non-turbo wagon. I did check the archives but they didn't really help, at least where I looked.

Thanks - a - lot

Billy Traweek

same thing happened to my 91 745 non-turbo. did all the usual stuff, finally I found a large hole in the underside of the rubber intake boot between airbox > throttle body. You'll have to remove it & carefully inspect. the oem replacement (Volvo) was not rubber but plastic & had the plastic elbow at throttle body moulded in to make the 2 - piece setup into 1 - piece.

definitely need to check this out, good luck !

Per those 700/900 FAQ's, read out the fault codes on the OBD system, then get back here with your findings. It could be something as simple as bad/corroded connections on the coil and power stage unit ($0.00 to fix), or something "serious" like the crank position sensor ($50.00 to fix).

Thanks Cris,

The OBD system is acting screwy. When I move the test lead to the test sockets and press the button I get a quick flashing light. No codes.

Thanks all,

Are you holding the button long enough. Some peoples' opinion is that you have to count slow.

Cris,

Yeah, I have held it for 3 LOOOOOOONG seconds and it still flashes at me.

Hrumph!

Billy - check out the 700/900 FAQ's - I'm confident you'll find several possible causes and their fixes there.

Just offhand, two possible cause that have resulted in symptoms like you describe in my '87 740's include first fuel pump relay (pull and resolder ala Don Foster's well described technique - the FAQ's should have even a photograph on this one.) Second could be dirty throttle body. This results in intermittent dying at idle because the gunk in the throttle body chokes off the air more than the computer can compensate for.

Both fixes cost nothing but a few minutes time, and are easy.

Since you might want to keep a spare fuel pump relay in the car anyway, you could buy a new relay ($40) and swap them, and resolder your old one for a spare. Cleaning the throttle body just takes some carb cleaner and a rage.

Have fun.

oops, meant "rag" not "rage." Don't take out your rage on your car with a can of carb cleaner.

It's Monday. Typing skills are a bit weak today.

Rob,

Thanks a lot for the response. I was reading the down loaded FAQ's as your message came in. I have already reflowed the solder connections and bench tested the fuel relay and the TB was recently cleaned. I would be having fun but this is the wife's car and she isn't as amused by the car's antics as I am.

Still looking,

I am not to the rage stage yet, I wasn't going to beat on the TB after trying to drown it with cleaner, although gaging it with a rag crossed my mind