My 1996 850 GLT wagon just began running and idling roughly. When you are driving the car it will nearly die and then began running fine, nearly die again and then run fine. It just does this constantly. It also does this when idling. When I start the car it runs fine for a couple of seconds and then starts to die. Just when you think the car will kill you get a strong gas smell, then it "catches" and the RPMs jump up to about 1500 for 1-2 seconds then returns to a normal idle. After just another 1-2 seconds it will go through it all again, nearly die, catch, RPMs jump and then return to normal. If you leave the car running it will just continue to go through this cycle.

Any ideas? Fuel pump or filter?

Thanks,
David

 

Hi David,

Try finding a local auto parts shop that does a free diagnostic (AutoZone). They can find codes in your engine computer.

I doubt it's the fuel filter, but could be the pump or the pump relay. More likely , though, people have had similar problem due to MAF sensor or idle air control. I'll give you a URL for the MAF sensor.

http://volvospeed.com/Repair/maf_secure.php

Also, check for vacuum leaks.


JPN

 

David,
I had the exact same thing happen when my father cleaned my engine with high pressure water. After a very difficult drive to the dealership, they took the top off the engine and removed the spark plugs, dried everything out and it was as good as new. We also added isoheat to the fuel, that helped too.

I've added a photo of the "top" they took off - lined in pink. Somewhere under-there, you will find a overflow hole and extra areas for it to "leak" to. This is how I got the water in my spark plugs.

I don't know if this is your problem, or the solution, but it's my $.02. I hope you get it fixed soon!
TealTank!

[IMG]local://upfiles/12395/49F75EDD8AA2475C9A72823B2096E8FB.jpg[/IMG]

 

+1 for getting it hooked up to an obdII scanner.

It definatly sounds like a bad maf.

Nick

 

Hi David,

I agreee with white out. This exactly happened to me last winter. Exact same symptoms. The folks here at Volvo Forums helped me to determine the problem. It was a MAF (Mass Airflow Sensor) that is connected to the air box. I went and got one off a junk and viola, the problem disappeared. Go volvoforums.com!!!

Shak.

 

I also believe it is MAf, but hooking it up to a scanner and getting the codes reas will not hurt either. I would also suggest a tune up in the near future. One thing you can do is check to see if you have any broken/disconnected vacuum lines. Please keep us posted.

Glenn

 

taking this car to autozone to get dtc checked WILL reveal if the MAF is the problem. I guess it is better to verify before replacing parts randomly. With that said, it does sound like your MAF may be the problem. If your check engine light is on, just go to autozone to verify.

 

By accident, I found if the problem is the MAF, disconnecting the electric connection to it puts engine in limp mode and engine ran fine, confirming a bad MAF unit. Before buying a new unit, I would get a spray can of MAF cleaner, remove the MAF(no big problem and using the cleaner, be sure the small detector inside the MAF is cleaned up. It's worth a try rather than jumping off right away and spending $150-200 for new unit.