1995 Volvo 850 2.0 stalls when warm.

Annema1 · Post by **Annema1** » 23 Dec 2016, 15:10

Hello,

My 1995 Volvo 850 (pre-OBDII) has been in a garage for a year now, but this problem started about 3 months into this year. The problem is that when I start the car all is well and it actually starts incredibly fast even with sub 0 temperatures, but when it gets warm about 10 minutes later it will run with what sounds like some sort of misfire. When I give it some gas it will run more smoothly but when I hit the gas too quickly it will sputter and stall if I don't release it. Eventually it will stall and when it does it WON'T start anymore, no matter what I try.

What have I tried so far:
-Checking fuel pressure before and after the stall by pushing the little pin(it squirted out so I think this is good).
-I closed the hot air valve going to the airfilter becasue the airfilter got very hot and this did make my problem occur later, because the engine takes slightly longer to warm up.
-I think I checked the MAF correctly by disconnecting the cable but this did not change anything and I did not get the check engine light that was supposed to happen???

I have asked multiple people about this problem but so far nobody knew what it was. Before this it ran great and had no problems. I hope some of you have some suggestions because I can't seem to find anyone with the exact same problem and I don't think a mechanic will be able to find what it is either.

Thanks in advance,
Sergej

Post by **rspi** » 23 Dec 2016, 20:24

If you disconnected the MAF and nothing changed, the MAF is probably bad.

Annema1 · Post by **Annema1** » 25 Dec 2016, 08:02

Thank you for your reply. I forgot to post the error codes I got:
A3: 122, 141, 412, 413, 414, 421, 422, 444.
A7: 113, 122.
I did check what those were some time ago and as I recall they were for ABS and something else but not for any engine related issue.

So if it still stalls when the MAF is disconnected I can assume that the MAF is broken? My (european) MAF has 2 pins btw.

Thank you for your effort,
Sergej

Post by **abscate** » 25 Dec 2016, 11:54

That's actually leading you away from the MAF, Sergej. It's more common to have a bad vacuum hose leak somewhere

Annema1 · Post by **Annema1** » 25 Dec 2016, 14:56

Thank you for your reply but I seem to have made a mistake. As I only just red on another forum my 850 does not actually have an MAF sensor but a temperature sensor in the location of the MAF on other models, and an MAP sensor. I am not sure wether or not this is correct, but it seems to be as my "MAF" sensor only has two pins... I hope you know something about this.

I will do some research about this MAP sensor now.

Once again, thank you for your time,
Sergej

Post by **abscate** » 25 Dec 2016, 17:33

I think we are confusing things. Can you post up a picture of your sensors and MAF

Annema1 · Post by **Annema1** » 25 Dec 2016, 18:18

I checked the engine bay and indeed, I have an MAP sensor above the radiator fan. This apperantly means I don't have an MAF.
This is my air temperature sensor on the airfilter:
https://www.ipdusa.com/products/9281/12 ... rex-regina

This is my MAP:
https://www.google.nl/url?sa=i&rct=j&q= ... 1368728074

I hope this helps to clearify it.

Post by **abscate** » 25 Dec 2016, 19:41

I think you have both a MAF and a MAP on this car.

Annema1 · Post by **Annema1** » 26 Dec 2016, 03:05

But where would the MAF be located if the sensor at the end of the airfilter is a temperature sensor?

Post by **abscate** » 26 Dec 2016, 05:47

Find the throttle body, with the cables attached. Follow the largest hose back towards the air cleaner and the MAF is in that loop. I'm sure you have closed loop lambda sensor fuel management on this car which means it has a MAF