1998 volvo v70 stalling, 5 codes

Jonc123 · Post by **Jonc123** » 23 May 2013, 20:33

I have a 1998 v70 that keeps stalling after about running for about 10 min. the car wont start back up for another 15 min, then starts and runs fine until it gets cold again. I was having the problem with no codes before but the cel just came on with this
p0340 cam sensor
p0103 Maf
p0455
p0442
Now I can easily install a maf and cam sensor but would it be necessary to change both? or just one? are they related? any info on the other codes too? any help will be appreciated, Im thinking about selling the car for cheap.....Thanks

socompsp · Post by **socompsp** » 23 May 2013, 21:46

try cleaning your maf sensor then unplug both cables that run to the battery. touch the pos and neg cables together (OFF THE BATTERY) todo a hard reset. then leave them off for about 30 min to be sure codes are gone. if it keeps stalling go ahead and replace the cam sensor, clear codes and see what happens. you can also just try disconnecting the maf sensor and see if theres a change.

Post by **abscate** » 24 May 2013, 09:46

Jon - dont dismiss the possibility that you have one major thing wrong with your car, and the poor running is throwing a bunch of codes out that dont necessarily point to bad parts.

The P0455 and P0442 codes are EVAP system faults - the poor running might have blown off a vacuum line in the evap system for example.

The codes guide you, but you still have to diagnosis spark, fuel, compression ...in that order, to do this efficiently.

I would suspect a fuel pump relay if it is a sudden quitting of the engine, for example.

Post by **jblackburn** » 24 May 2013, 22:06

If it won't run again with the MAF unplugged, it's not the MAF. Doubt the EVAP codes have anything to do with it whatsoever.

Id actually be inclined to pin this one on:
1) an overheating positive battery cable (feel the one heading to the fuse box when the car dies - is it extremely hot???)
2) An overheating/failing cam position sensor as indicated by the code. They get flaky with age and high heat.

Jonc123 · Post by **Jonc123** » 28 May 2013, 07:39

ok did some more research, Im going to go ahead and replace the cam sensor first. Now my question about the MAF....I had the car running at idle and unplugged the MAF, the car ran ok with it disconnected but when i plug it back in it stalls....is it bad?
Thanks for the help....

Jonc123 · Post by **Jonc123** » 28 May 2013, 07:41

abscate wrote:Jon - dont dismiss the possibility that you have one major thing wrong with your car, and the poor running is throwing a bunch of codes out that dont necessarily point to bad parts.

The P0455 and P0442 codes are EVAP system faults - the poor running might have blown off a vacuum line in the evap system for example.

The codes guide you, but you still have to diagnosis spark, fuel, compression ...in that order, to do this efficiently.

I would suspect a fuel pump relay if it is a sudden quitting of the engine, for example.

Is there a way to test the relay? with an ohm meter or something?

Post by **abscate** » 28 May 2013, 08:01

There are numerous posts here about bypassing it and seeing if that QUITS your quitting problem...I think that is the best approach.

Jonc123 · Post by **Jonc123** » 28 May 2013, 08:49

another question....If the cam sensor is bad then the car wont start at all right?

Post by **jblackburn** » 28 May 2013, 09:35

Jonc123 wrote:another question....If the cam sensor is bad then the car wont start at all right?

Depends how it failed. It may fail only when hot...in which case, the car would start and then die out when it loses a reading from the sensor.

Jonc123 · Post by **Jonc123** » 28 May 2013, 09:49

jblackburn wrote:
Jonc123 wrote:another question....If the cam sensor is bad then the car wont start at all right?
Depends how it failed. It may fail only when hot...in which case, the car would start and then die out when it loses a reading from the sensor.

It doesn't stall out when hot, Just when i drive down the road and come to my first stop. However I just disconnected the mass airflow sensor and the car did not stall out. It ran a little rough but didn't stall. So im going to go ahead and replace the MAF sensor. Im just not sure where im getting the cam code from so I inspected the connection and cleaned it out....