I have an 1994 850 wagon 245,000 miles

Engine would just die, not studder or cough, but just stop running as if someone turned off the igniition. woudl pull over, wait a few minutes, and car would start.

I checked the codes (this is an old OBDI) and came up with cam position sensor. Replaced it, cleaned MAF carefully with CRC plastic safe electronics cleaner car is running fine now.

When first checking codes, I missed this code because I did not scroll through all the codes

Early in this car's life, the crank position sensor went bad, engine would studder and not start.

Check your OBDII codes with a code reader - many auto parts stores will do this with no charge. But make sure you scroll through all the codes.

 

I'm leaninmg towards CPS too. Seen a few go bad and cause drivability issues before utimately causing a no start condition.
9k deep in parts IS getting a bit pricey, and depending on your resources, even borderline silly.
Please don't take offense, I'm in the same boat as you with one of my vehicles.
Please let us know what the verdict is; maybe shop can diagnose and we can help with the repair! GOOD LUCK!

 

P.S. In reply to Koan, my failed CPS was missed by an Autozone scanner on an OBD-II vehicle. Shop scanner picked it right up.

 

replying to BPATR1CK and Phatman

My 1994 850 is the old OBDI press and count the flashing lights deal. Intersting that a shop scanner would see a code a normal OBDII scanner would not. I wonder what would cause this result, particullarly for a cam Pos sensor. For the OBDI code - there is actually an intermittent signal loss code as well as signal missing. I went to a junkyard and got a CPS for $30 to give it a try - guess I got lucky. Symptoms seem similar though - car completely dies - then starts and runs as if nothing happened - and this became more and more frequent.

I have also had the host of other Volvo engine maladies - Fuel pump relay, fuel pump wires faulty, fuel pump in-tank screen clogged, cracked vacuum elbow under fuel rail, fuel rail valve leak, injector o rings leaked, egr sensor dirty, MAF dirty, MAF connector needed cleaning, and injectors dirty. In all these cases though - the symptoms were engine running rough or stumbling NOT switching itself off. Getting a shop scan seems like a good suggestion.

 

Well, apparently the crank position sensor had metal shavings on it, most likely from when the teeth on my flywheel sheered. Shop had it running once they cleaned it but then realized that the Ohm reading on it was also low so they are replacing it, should know later today, if that was the whole problem.

 

So, after a whole bunch of crap, Crank and Cam position sensors replaced, ECU rebuilt, wiring harness traced, my car still won't start. Mechanic wants 1500 bucks and says he gives up. Apparently they are putting a Noid light on 1 of the injector wires and they are not getting pulse.

Anyone have any ideas? Could this be a malfunctioning ETM?

If I take a baseball bat to it in the mechanics parking lot does my insurance cover me?

 

...know i'm going to regret this...

Is he getting pulses from the cam and crank speed sensors when the engine is cranking? If answer is no for either, then that's your problem. And no, it's not necessarily the sensor itself.

Plus if he can't fix it, he should take off any new parts that he installed, not charge you for any parts or labor; maybe some minor shop supplies charge, but that's it. When you OK'd his estimate to repair your car, there's an inferred and written contract that he will fix it; if he can't complete the contract, then you should not be obligated to pay. Sucks to be him but...

If he doesn't see it that way, take it up with your attorney general's office...

 

So, after all this, I paid the mechanic for the parts at cost($961, Crank and Cam sensors, Fuel Pump and Main relay, ECU Rebuild), took it to another shop that specializes in Volvos a couple towns over, and gave them an hour to see what they could tell me. Within 15 minutes of looking at it, they had it purring. Turns out there was a plug that wasn't fully plugged up on the fan shroud. Mechanic at the second place said he doubted that I needed any of the new parts the other installed. At least its running, Hopefully I can get a good amount of mileage on it, before I have to drop anymore money into it...... but I have to go through my emissions test within 30 days of tomorrow so we'll have to give it a day to see if the Cat light comes back on.

 

That's the difference between a (real) tech and a parts-changer..

The tech will spend your $$ on what's needed to fix your car, and the parts-changer will just spend your $$!

 

phatman: Please let us know what that plug was for, to what system did it run, so that we can be on the lookout for the same thing. Thank you, and glad you got it figured out

 

Its the connector, you see just below the air intake. Not sure exactly what system didn't get that in-depth when speaking to the tech, but it'll keep your injectors from getting pulse if its not fully plugged.