Hey, so I recently picked up a ‘96 Volvo 850 and after the last few weeks of driving it I’m experiencing the car stall out when moving the car from park into reverse or drive, while in park and neutral it’s idling at about 1500 rpms, if I get the car moving it drives and will run and start up like a dream for the rest of the day. Was reading online that this seems to be a maf issue so I replaced that yesterday and the car was after some time back to running well but went out to start it this morning and was running into the same issue again. Any ideas about what this could be?

 

Sounds like a vacuum leak to me, but I admit confusion about the fact that it drives fine the rest of the day. That's odd. Does this car have a turbo? Lots of differences there in the sorts of problems you have measuring air flow.

 

Non Turbo Model, got home after work today pulled out the throttle body and IAC cleaned them both thoroughly and reassembled everything and tightened it all down properly. Still having some weird idling issues in park and neutral but seems to be running better, gonna let it sit overnight and see what happens in the morning when I go to drive it. For other general contexts, when simultaneously gassing and braking in drive the car will either stall completely or roughly idle and lurch hard, the night before these issues popped up an oil change was done because a tech accidentally started one when changing out my front tires. Noticing no oil leaks, coolant leaks, or any issues with transmission fluid. My first gear shift does almost feel like its kind of stutter stepping into gear but is inconsistent and I'm assuming engine based rather than my transmission. Also since I purchased the car in early December the car has been getting the engine too rich code p10172, while lately give or take ~100 miles has not been present nor have any codes. The car isn't down on power either so its really got me lost as to what's wrong with it.

 

These cars have a known issue where the coolant temperature sensor goes bad and that makes them hard to start. It's winter where I am, so it's a good time to have that problem as well. On a 96, you can use a scan tool and actually read what temperature it thinks the coolant is. You can second guess the accuracy yourself.

The non-turbo cars ought to run pretty well with the MAF unplugged unless you have a 2nd problem. At least I've seen that.

 

I'll have to look into the temperature sensor, some updates since my last post, on the highway my transmission light started flashing drove it back home got a check engine code that i've been getting again wiped it both lights have turned off since. Driven about 40 miles since. Was checking something earlier and went ahead and checked my heater core sense it went out on my "00 v70xc when I first bought it and noticed a small coolant leak on the seam of it, going to get that replaced asap but wondering if it is possible for that to be whats causing my issues with stalling and putting the car in gear.

 

So I've done a whole laundry list of work to the car now with no progress, it has actually gotten far worse than it originally was, the car now consistently stalls when shifting into Drive or Reverse unless you gas it to all hell and in which case it'll drive with no lack of power but will without fail stall every time you come to a complete stop. I have changed the MAF, cleaned my throttle body and IAC, changed the thermostat and engine coolant temp sensor, as well as the fuel filter. I am at a total loss with this problem and could really use some help in what direction to head in next.

 

Another follow up checked fuel pressure, at idle in park its at 35 psi and at prime its at 39 psi, wasnt able to check at throttle since i was alone.

 

Ran some smoke tests looking for vacuum leaks after everything else came back okay, found a vacuum leak last night wasn't able to find out where from until earlier today when I did another smoke test, found the leak on the crankcase vent hose that runs under the intake manifold, barely bumped after finding the leak and it snapped into 3 separate pieces. Part is ordered and comes in on thursday, if i do not come back to update the thread this is the solution.

 

I replaced the crank case breather hose that was causing the vacuum leak, there was no improvement, car is still stalling when put in gear as well as when you come to a stop when you launch it to drive it. I really could use some help with any ideas of where to go next with this please

 

Unplug your IAC (Idle air controller) and see what happens. You can drive the car without one powered, but it will surge and act funny when idling. Mine malfunctioned and was constantly closed when powered, which caused my car to stall and die when put into gear.

 

tried that and it did not work, thank you for the suggestion though

 

The car is still not able to be put into gear without stalling, updated list of maintenance includes: replaced crank case breather line, the hose running from breather box into the engine (little L shaped hose), hose running into the top of engine from the breather box, the throttle body gasket has been changed as well as the intake manifold gasket, I have a brand new volvo air intake hose on the car (fixed the vacuum leak between the crank case breather hose and the air intake hose), upper idle air control valve hose. The lower one has been patched up to the point of no smoke leaking out through 3x different smoke tests, I have a new hose coming in soon anyway to go ahead and replace it anyway. Really at a loss here, When you launch the car in L to get it to drive it still fully stalls at a full stop as well as putting it into drive and then turning on Winter mode the cars idle drops down to about 400 ish and the car shudders hard and gassing it does not allow for the car to really move at all, way way down on power in Winter mode pretty much. any insight or advice on where to go would be nice.