1986 240dl Stalling

Post by **rgk** » 06 Jan 2015, 18:01

I have this same problem. It was really bad until I made sure the connection and vacuum to the ECU was very good. Now it is still problematic sometimes, but not as often. I am thinking about replacing the plastic vacuum hose between the intake and the ECU. If I had access to another ECU I could test the one I've got.

You said fuel was shooting out of the fuel pressure regulator. Was it shooting out of the vacuum hose? That shouldn't be so.

Edger · Post by **Edger** » 06 Jan 2015, 18:30

It was coming out the return port to go back to the fuel tank.

Edger · Post by **Edger** » 06 Jan 2015, 18:53

And where is the ECU on this auto?

Post by **rgk** » 06 Jan 2015, 19:46

It is an oddly-shaped black rectangular box mounted at the front of the engine bay on the right side, near the winshield washer fluid reservoir. It will have a wiring harness as well as a vacuum line going to it.

Edger · Post by **Edger** » 08 Jan 2015, 21:08

Found the ECU, I checked the vacuum line to it and I have a vacuum to it. How do you tell if the ECU is going or gone bad? Are there any other vacuum lines that run in tight places on this auto. Will a dirty throttle body cause it to BOG down like this is doing. Just going thru steps to see what is going wrong. any info will be greatly appreciated. Also if the piece that the vacuum line goes into the ECU is bad will that do this too and is it replacable?

E

Post by **rgk** » 09 Jan 2015, 05:48

I had vacuum too, but you never know. Did you ckeck the terminals/solder points for looseness? Did you reseat and clean the connection? A bad ECU won't always look bad.

I was wondering yesterday: might this be symptomatic of a bad throttle position sensor?

Edger · Post by **Edger** » 10 Jan 2015, 12:46

How do you tell if the TPS is gone bad?

E

Edger · Post by **Edger** » 10 Jan 2015, 15:32

I had a test to do on the fuel regulator that another mechanic suggested. While ideling in park I reved up the enging and as it started to spit sputter and BOG down, that is when I applied a pair of pliars to the return hose that goes back to the fuel tank. It cleared up and caught up with where the throttle was at. SO could it actually be a bad fuel pressure regulator I actually have? I am thinking of taking a small clamp and putting it on the hose to restrict the flow a bit to see if it will run in good order now when I put him in drive. If that is what is wrong with my dear VOLVO I will get him a new regulator. I can almost see the clouds parting. Lets see where this takes us. Keep us in your prayers.

Edger

lummert · Post by **lummert** » 10 Jan 2015, 16:14

A failed FPR can send most of the pressure back to the tank. Were you able to use a fuel pressure test kit to check fuel pressure?

Edger · Post by **Edger** » 10 Jan 2015, 22:06

There is no valve on the fuel rail to test at. But I will test the clamp in the morning and hopefully all will be revieled.

E

1986 240dl Stalling

Re: 1986 240dl Stalling