Hey all, I have been slowly but surely whittling away my stalling problem in my 86 240 DL. To recap, the car starts fine and will idle with no issue. While in park or in Neutral, even in Reverse, the car will rev up with no issue at all. As soon as the car is in drive and I give it gas, she stumbles and will occasionally die. If it gets passed the stumbling, the car will run at a steady speed with no problem but as soon as i try to accelerate a bit more she goes quiet (stumbles) as if the car is searching for a gear.

Heres what I have done so far:

- New cap/ wires and spark plugs
- Replaced the fuses
- New MAS
- the fuel pump was replaced right before i inherited it

I can hear the fuel pump and I believe the in-tank as well ( issue will occur with a 3/4 full tank )
I have been replacing Vacuum hoses as I see them however I have a hard time identifying a few of them as well as a few other wires/plugs

If you could help with ID that would be greatly appreciated, and if you have any other ideas what this could be please let me know. I just wanna get this baby back out on the road!

Thank you so much to all!

 

Here are a few pictures....1 at a time since my phone is fighting me

 

And another, anything go on this here?

 

And the last for now, can you ID where this should be plugged in?

 

That looks to me like the nipple on the fuel pressure regulator. Should be a hose from that nipple to a nipple on the intake manifold.

 

Would that hose that is in picture one be the hose that goes to the nipple? that would make too much sense wouldn't it... geez sometimes things are too obvious. Could that possibly be causing the issue do you think?

 

Probably...the fpr needs vacuum to work

 

The hose in the first picture (the one with the tape on it) should go to the fuel pressure regulator. The fuel pressure regulator's job is to keep the fuel pressure to the injectors a constant pressure above manifold vacuum. Without that hose connected, the regulator is not going to know how much vacuum in the manifold. I'm not sure it would keep the engine from starting but for sure it will not run well.

 

Great! Thank you so much for the info, I will be getting it hooked back up tonight. Now since there hasn't been a hose attached to it, I'm sure it's now dirty and disgusting...any idea how to check if the FPR is still in working order?

 

you test the fuel pressure regulator with a fuel pressure gauge.

but, there's no airflow thorough that connector on the FPR, its just a vacuum port.

 

Battery terminals was a big issue for me when I tried getting my 85 740 to run. Also all vacuum hoses were quite old and making some funny squeaky noises. Have you tried to clean out the PCV oil catcher?

 

If the vacuum hoses are making squeaking noises then they are leaking from cracks in them. They need to be replaced. The one going to the FPR in your first photo has tape on it which probably leaks. Any vacuum leaks on these engines generally cause poor performance and poor running.