93 Volvo 850 dies while driving

d-roc · Post by **d-roc** » 24 Dec 2012, 22:50

I am new to this site, but have used it as a resource many times in the last two months since acquiring my 850. It has been a work in progress but the biggest problem I was having was the car would die at low rpms. I had a faulty camshaft position sensor and replaced it which prevented the car from dying while driving at regular speeds, like on the highway. However, at lower speeds and turns it would still die occasionally. After cleaning everything related to the throttle body, maf sensor, and replacing the ignition coil it would still die. It would usually start right back up after shifting it down to low and back to park, but it was very annoying. I came across a few threads mentioning to replace the fuel pump relay and also the ignition relay. I went to the pick n pull and got both relays and replaced them yesterday. The car has not died yet at low speeds. I just post this as I hope if someone has a similar problem that this might help. And if it dies again, I'll be back asking for help. Thanks for all the previous posts that helped me so much.

Post by **rspi** » 24 Dec 2012, 23:04

Hi D-Roc, welcome to the site.

There is a chance that you got the problem with the relays. Usually low speed stalling is cause by vacuum leaks.

d-roc · Post by **d-roc** » 24 Dec 2012, 23:23

Thanks. I looked for a vacuum leak. I thought I found one from under the battery tray which I think is the cruise control. But apparently the one I found is not suppose to be connected to anything as it is a release valve. However I did find a black hard plastic hose with a 1/4" or so opening that's open ended by the battery and runs underneath the engine. I think it has something to do with the radiator because initially I connected it to the end of the valve I mentioned earlier and all of the sudden I had anti-freeze under my car.

Post by **Ben850** » 25 Dec 2012, 15:39

d-roc wrote:Thanks. I looked for a vacuum leak. I thought I found one from under the battery tray which I think is the cruise control. But apparently the one I found is not suppose to be connected to anything as it is a release valve. However I did find a black hard plastic hose with a 1/4" or so opening that's open ended by the battery and runs underneath the engine. I think it has something to do with the radiator because initially I connected it to the end of the valve I mentioned earlier and all of the sudden I had anti-freeze under my car.

Your '93 has what is called the VVIS intake manifold. There is a black plastic vacuum line that goes to an actuator under the manifold. It connects to a "T" check-valve which splits to a solenoid on the airbox, and a vacuum tank under the fender.
If that is unhooked there will be a vacuum leak drawing from the manifold junction. It will cause eratic behavior if it is unhooked.

Here is the vacuum diagram.

: Vacuum solenoid.gif (24.29 KiB) Viewed 2010 times

To be clear, the solenoid " I " is mounted on the airbox under the distributor cap area. It has a slightly larger than normal black plasic vacuum line running from it to the front of the engine, under the manifold to the servo " J ". The vacuum tank " G " is in the front fender, under the battery area, in front of the EVAP canister.
If this is hooked up correctly and functioning, you should feel strong accelleration whenever you reach around 4,100 RPM.
Good Luck.

d-roc · Post by **d-roc** » 27 Dec 2012, 18:59

Thanks for the diagram and the detailed explanation. I found the big black plastic line that runs under the manifold and that's connected. I also checked the other vacuum lines listed in the diagram and it looks like they are all connected. I haven't had too much time so I'll double check them this weekend. The line I found that's not connected to anything shows up just under the battery tray and runs under the cooling fan and disappears under the alternator. I haven't been able to get under the car to see where it ties into. I attached a picture. Thanks for the help so far.

Post by **rspi** » 28 Dec 2012, 02:59

Not to change the subject but, you need to get that coolant leak fixed asap. Over heating will kill that car quicker than anything else.

d-roc · Post by **d-roc** » 28 Dec 2012, 08:54

rspi wrote:Not to change the subject but, you need to get that coolant leak fixed asap. Over heating will kill that car quicker than anything else.

That leak stopped. It only happened when I incorrectly attached the unknown line to the end of a vacuum tree that was supposed to be clear.

d-roc · Post by **d-roc** » 03 Jan 2013, 11:59

Ben850 wrote:
d-roc wrote:Thanks. I looked for a vacuum leak. I thought I found one from under the battery tray which I think is the cruise control. But apparently the one I found is not suppose to be connected to anything as it is a release valve. However I did find a black hard plastic hose with a 1/4" or so opening that's open ended by the battery and runs underneath the engine. I think it has something to do with the radiator because initially I connected it to the end of the valve I mentioned earlier and all of the sudden I had anti-freeze under my car.
Your '93 has what is called the VVIS intake manifold. There is a black plastic vacuum line that goes to an actuator under the manifold. It connects to a "T" check-valve which splits to a solenoid on the airbox, and a vacuum tank under the fender.
If that is unhooked there will be a vacuum leak drawing from the manifold junction. It will cause eratic behavior if it is unhooked.

Here is the vacuum diagram.
Vacuum solenoid.gif
To be clear, the solenoid " I " is mounted on the airbox under the distributor cap area. It has a slightly larger than normal black plasic vacuum line running from it to the front of the engine, under the manifold to the servo " J ". The vacuum tank " G " is in the front fender, under the battery area, in front of the EVAP canister.
If this is hooked up correctly and functioning, you should feel strong accelleration whenever you reach around 4,100 RPM.
Good Luck.

So there was a vacuum leak to say the least. I had check all the lines under the hood but never checked under the front fender where the canister and reservoir are. Well i did not have the canister nor the reservoir. So i went to a yard and picked one up and attached it with all the lines. I followed the diagram under my hood but I don't think I did it right cuz the car still jumpy. The one I pulled from the yard had the line from the non return valve running into the canister but the diagram under the hood shows it runs into the reservoir. Anyone have any suggestions

pkuevor · Post by **pkuevor** » 03 Jan 2013, 15:30

I am having this exact same issue. It just happened to me last week on the freeway while I was in the passing lane...SCARY. I will save this thread.

d-roc · Post by **d-roc** » 12 Mar 2013, 00:18

Well, if anyone is looks at this thread, my car is finally running pretty well. I replaced, in the following order, the crankshaft position sensor (RPM Switch), thermostat and coolant sensor, cap and rotor, and wires. The car was misfiring at lower speeds and that finally stopped after I replaced the spark plug wires. She has been running pretty well since, knock on wood.