1996 850 Turbo Cooling Issue?

zyanmayfield · Post by **zyanmayfield** » 23 Feb 2014, 18:55

Hi,

I've been a stalker of this forum for a long time. Especially when replacing head gasket on one of my 850's. Thanks!

The problem I am having now is my car will drive fine when I first start it. Then after I have driven for about 4 or 5 blocks the car has a terrible time and often stalls on the start up from a light or sign. I know just enough about cars to sound stupid sometimes so my thought was that the engine is actually warm but the car thinks it is cold so it's having a mixture issue. Then I discovered if once it has this issue I pull over and and keep the engine held at like 4K-5K RPM for like 10 seconds or 20 seconds in intervals then it shoots the temperature gauge needle up to the middle and everything begins works perfect for the rest of the drive. If I don't rev it super high the entire drive is really difficult.

I changed the Thermostat cause at first I thought maybe it was stuck open or closed, don't think the logic on that worked out but I figured a couple of bucks and an easy job.

Got any Ideas?

Thanks!

Post by **Ben850** » 23 Feb 2014, 19:26

That was the issue with my '96 Turbo wagon when I bought it. I did swap out a lot of sensors to no avail.
Finally after vacuum lines, Turbo hose clamps etc... I replaced both O2 sensors.

They did the trick for me. I believe they finally let the MAF communicate with the ECU properly to let it perform in complete loop operation, and know if the engine was hot or cold etc..

The previous owner was basically selling the car for parts because he could not keep it running.

Lucky for me

Being a '96, if the O2 sensors have never been replaced, I believe you may be surprised either way at the difference.

My '96 Wagon thread.
https://www.matthewsvolvosite.com/forums ... 35&t=56550

Post by **rspi** » 23 Feb 2014, 21:20

If your vacuum lines are good and your intake tubes are fine, you might want to replace your ECT.

zyanmayfield · Post by **zyanmayfield** » 23 Feb 2014, 22:15

Great thanks! I will check my vacuum lines first. It does rev a bit to much when I start it up so that could be a possibility, although it has done that for a long time and this new problem is very recent. If that doesn't work I have another ECT laying around so I'll give that try. Wouldn't the check engine light be on if it was something like an O2 Communication problem? But I'll give it a shot after the easy stuff! Thanks guys! Hopefull have time later this week to work on it. I'll keep you posted!

Post by **Ben850** » 24 Feb 2014, 02:24

zyanmayfield wrote:Great thanks! I will check my vacuum lines first. It does rev a bit to much when I start it up so that could be a possibility, although it has done that for a long time and this new problem is very recent. If that doesn't work I have another ECT laying around so I'll give that try. Wouldn't the check engine light be on if it was something like an O2 Communication problem? But I'll give it a shot after the easy stuff! Thanks guys! Hopefull have time later this week to work on it. I'll keep you posted!

No. The front O2 will sometimes not throw a code.

zyanmayfield · Post by **zyanmayfield** » 08 Jun 2014, 11:15

Hey Everyone!

I made it back with the solution! It only took 4 Months to get time to work on the car.... The Connector that connects to the Temperature Sensors connector was bad. If I wiggled it one way it would show no connection and if I wiggled it the other way it worked. Guess that's why if I revved it a bunch it would maybe vibrate the connection to a correct spot forming a connection and shoot up the guage. Well thanks everyone! Hope this helps someone else later!

Post by **Ben850** » 08 Jun 2014, 12:56

Good to hear. At this age, electronics become the ghost in the machine.