Hi guys, I need help.
I have a 2001 V70 X/C. Car takes about 15 seconds of cranking then it starts and runs rough for about 30 seconds then it's smooth but while its running rough black smoke comes out of the tail pipe I changed the spark plugs today and they were black (too much fuel) no difference with new plugs, car has brand new fuel injectors, it had a coil go bad and kept ruining the after market ones until i got one from a junk yard that matched the original part number. I also did the throttle body upgrade with the no contact sensor, still with everything I've done no fix yet. I'm thinking about the cam and crank sensors, but I have only found the crank sensor and the cam sensor is not were the pictures on google show, this one is different. I need help guys please, thanks in advance.

 

did you check the coil packs? i had a similar problem when i first bought my wagon and i had 2 bad coils and 2 bad o2 sensors.......

 

Hi thanks. Yeah I only had one bad coil and changed it out already, when it was bad it lit the CEL but not anymore. Unless I do an ohm test but I wonder what specs I'm looking for? How did you find your bad coils by code reading or by other means?

 

you may need to drive it a bit to see if the CEL resets but my general experience is that a bad coil pack will set a P030x (misfire) code. O2 sensors are tougher to diagnose since an intake air leak can create an idle fuel trim error which may get blamed on the sensor. Did you try cleaning the MAF when you did the throttle body? Cam/crank sensors will also usually set a CEL, but you can start by popping off the timing belt cover to see if there's any oil leaks from the VVT gear. Finally you may have a fuel pressure issue - not sure if you model has a regulator/pressure sensor etc but you may want to pop on a pressure guage to the rail and see how it measure up at idle and when driving.

 

I did clean the maf sensor with the special cleaner from crc
But I will give it a drive and report back. Like I mentioned the car seems to run and idle fine after its been idling for a few minutes, but nonetheless I shall drive it and report back thanks.

 

Ok checking in. I drove the car on the highway for 30 miles, at about 14 miles the car started jerking a little not very rough, I had a code reader plugged in the whole time at this point no CEL but I checked anyways and Only P0134 O2 sensor no activity was now there. A few miles later the CEL flashed a few times but didn't stay on now it added 3 more codes PO300 random/multiple misfire P0301 & P0305 cylinder 1&5 misfires, funny that cylinder 1 came on because that is the one I recently changed. Any thoughts?

P.S. Car started cranked for about 15 seconds before it started and when it did idled rough for about 30 seconds then it felt fine, then after 14 miles the above happened.