hi, i have an 850 GLT 2.5 20 valve that cuts out while driving. coast to the side of the road, wait 1 or 2 minutes, it will restart and drive fine again. what do you guys this could be? anyone think they can help. thanks. RAT

 

Hey Rat: I don't think your problems are related, try not to link them together because you confuse yourself and others.

The #1 reason a Volvo dies is the fuel pump relay or the fuel pump. The #3 reason is the battery.

No, the fan does not need the AC charged to work, you have yet another problem. Search the site to find out how to fix those things.

 

I second what rspi said, spot on.

 

+1 with RSPI,
But, What about a clogged PCV?

 

thanks

 

I think a clogged PCV system will blow a seal or two before it causes the car to stall. Our S70 was blowing the oil dip stick.

 

If your PCV system clogs the effect is no scavenging of blow-by and condensation out of the crankcase. It would be like closing off all the vacuum ports the system connects to. The idle air control valve would just open a tad more to make up for the slight reduction in flow through the vac ports.
Yes, you would most likely be pushing a bunch more oil past the various seals from the pressure if not pushing the seal out itself.
The system if it was leaking could cause a problem at idle allowing the engine to die if the IAC motor couldn't react fast enough but at cruise with the throttle plate open vacuum doesn't play a very important role as far as a small leak being able to be noticeable much less shut the engine down.
If you had a break in one of the intake tubes after the MAF sensor, you bet that can sometimes kill it. A loose intake tube connection or broken elbow that pulls open when accelerating (usually helped by a bad motor mount) has been know to stumble or kill an engine.

It sounds like the relay is failing or possibly the pump. Something is heating up past it's operating point and once shut down cools fast enough to be functional again. Of the two the relay is the easiest and cheapest to replace and might be worth the chance. Even if it doesn't fix it it's still not a bad bit of insurance. If you still end up having to do a pump you're not stranded in a day, a week or a couple months if the present relay finally failed too.

 

I had a similar problem a few years ago, and it was the fuel pump relay. I replaced it and haven't had a problem since.

 

thanks i try relay

 

hi guys. i ordered a new fuel relay, still waiting for it to turn up hope it fixes it. did the diagnostic test come back with the codes for the mass airflow meter malfunction? but i don't think it woulsd cause it to cut out while driving as the car runs so good and smooth and just stops. rolls to the side with the ignition lights on. hope the fu el sensor sorts this problem out. thanks. PS. how do you reset the engine management light and the service warning light? once i put the air mass and fuel relay, will that reset it automatically or i have to reset it somehow? thanks RAT.