Hi,

I have a 1996 volvo 850 automatic transmission with 132k miles on it.

I've spent the last 45 minutes browsing the forums here + some other websites trying to figure out a solution to my problem but haven't been able to come across anything yet. I did read the other thread on here about code p0103 but it doesn't really pertain to my issue.

My car started running sluggishly + stalling at stop signs / in traffic on thursday night and then finally stalled and refused to start again on friday morning. The mechanic I brought it to said it was a MAF problem and said it would cost 395 dollars to replace / repair (lol).

I took out the MAF and cleaned it with dielectric cleaner and tried to put it back in and the car would have a rough start and run very rough. Did not try driving it at all.

Tonight I replaced the malfunctioning MAF with a MAF I picked up at the local junk yard and it's running slightly better but still very rough / feels like its going to stall out. Still reading error code p0103. It runs pretty decently but kinda rough when you disconnect the MAF.

Code p0103 ( http://www.obd-codes.com/p0103 ) is for high voltage on the MAF. I'm beginning to think this is an electrical / circuitry problem but don't really know where to go from here. I can't swap out the relay switch because the one the MAF is on is unique.

Anyone run into something like this before? Any help is appreciated.

 

Do you have 12v pwr to one of the terminals at the MAF sensor connector? It's terminal 3 (grn wire?) on 95 850; not sure if it's same on 96 but likely is.

 

update: The 4th pin on the connector to the MAF is reading around 2.5-2.6 volts. does anyone know what this pin controls / whats this wire do?

 

The MAF has two circuits, much like the HO2S. Two terminals are high impedance (very sensitive) sensor terminals that are read by an ADC (analog to digital converter) in the ECU. The other two are heater circuit terminals that should have full DC bus voltage shortly after the engine is started. The heater is used to burn microscopic contaminents off the the surface of the sensor so it gets very precise real time air flow data for the ECU. From what I understand, and have experienced, the MAF is what directly controls the air fuel mixture in these cars.

I've had great success just unplugging the MAF. They don't run perfect but our 98 V70 was stalling at just about every stop so I unplugged the MAF and it stopped stalling. The turbo would not run with the MAF plugged in so I unplugged it and bough it right. I replaced both MAF's with a brand new ones and the cars have run perfectly ever since. I did buy a new MAF off Ebay for my 96 9850 turbo for a great price and it has worked perfectly. PM and I'll try to find the name.

 

i have 2 perfect working ones if interested PM me

 

I talked to another mechanic the other day. He says it is probably related to work the previous mechanic did who replaced my exhaust manifold the day before the car broke down. I'm thinking they may have replaced a wire harness poorly and caused it to melt or something to that effect? Any ideas on how this issue could be related to work being done on the exhaust manifold? I'm taking it to a new mechanic tomorrow and will update with a final diagnosis + solution for those interested.

even with the MAF disconnected it starts + runs extremely rough and belches some dark smoke out the exhaust