Endless running problems on 99 V70 AWD - B5254T

Mokomaki · Post by **Mokomaki** » 15 Mar 2016, 01:19

Hey, i'm desperatly in need of some advice.. i've already spent more money on repairing this car than the whole piece of crap is worth.
Some time after i got the car my timing belt jumped... it was towed to a shop and the mechanic noticed that the previous owner had mixed two different coolants, whole system was bogged and cylinder 3 was almost burnt.

Now 2200€ later i've had him do a complete service.. Head gaskets, timing belt, all 20 valves, oil flush and filter, fluid flush and refill. etc.

But STILL after the repair the car is idling very rough.. Almost like a "racecar" and the whole engine is unbalanced and shaking.. So im assuming some problem in ignition?
Its also running rich, cause it smells of fuel, and the exhaust is popping on downshifts..

Yesterday i tried replacing the middle ignition coil, but no change... at the same time i noticed that once again my engine was covered in oil, that had came from the PCV hose coming to the top... I already did a PCV service a week before my timing belt jumped.. Replaced the breather box and all. Only thing i didnt touch was the PTC valve... Also just yesterday there was so much pressure, that after tightening the top breather hose and starting the car up, the hose came off during idle.. Didn't rev the engine at all. Also when the engine is cold and im driving about 40km/h on 2nd or 3rd, when the revs drop under 2000 it starts to stutter earlier than normally.

But what i've tried so far:
IAT sensor
MAP sensor
MAF
changed plugs..
Changed a coil, and tested all coils by pulling the connectors on each one.
checked for vacuum leaks, even changed the intake manifold gasket again.

Also no fault codes, or CEL

Heres some footage on how it runs...:
- https://www.dropbox.com/s/3ut8ffj7exh1x ... 2.mp4?dl=0
- https://www.dropbox.com/home/Photoshop/ ... 154325.mp4

Post by **Ozark Lee** » 15 Mar 2016, 08:13

It sounds like there is a massive vacuum leak somewhere which will cause the car to run horribly. You can actually hear the hiss from the leak in the video. I am really surprised that you don't have a lambda light.

Check all of the vacuum lines and also check to make sure that the intake manifold is bolted on tightly and that nothing (wire or vacuum line) got stuck underneath the manifold when it was bolted back on.

...Lee

Mokomaki · Post by **Mokomaki** » 15 Mar 2016, 08:32

Already changed the intake manifold gasket. And tightened.. Tried brake clean spray test and no spike in idle.
Apparently that dreadful hiss is coming from the timing gears/belt.. After the belt swap...

Mokomaki · Post by **Mokomaki** » 15 Mar 2016, 10:56

I'm actually suspecting the IAT sensor. I changed it to a one that was also used and had broken clips... Maybe i should order a new one from volvo..
Cause i did wiggle the sensor and it did run normally for s few seconds. Also disconnecting the battery causes the car to run normal, until i take off