2000 V70 Running rough, misfires

[asfd]

I have had problems for a few weeks with a 2000 manual non turbo V70. It started coming back from work with misfires and flashing check engine light. Since then it does it quite frequently under various loads. I changed the spark plugs but it didn't help. I bought an OBD 2 Code scanner today and hooked it up. The error codes were as following:

P1670: Volvo Immobilizer Control Module Communication Error/Code Error
P1612: Throttle unit communication Signal too low
P0300: Random/Multiple Cylinder Misfire Detected

I think I might have two different issues going on right now.

First, before I bought my OBD 2 readerb I thought I might have bad spark plugs (hence I changed them) or ignition coil (didn't change them before scanning) but am I right thinking it might be the antenna ring of the immobilization system that might be failing and cutting ignition thus causing misfires?

Might the throttle unit communication problem be an ETM issue. I think my car is still under the 10 year extended service for this and I don't know if it has been changed. I am thinking about this because while reading on this topic I recognized some symptoms I experience such as: uneven idle, dipping revs while slowing down at stops and lights and even sometimes stalling while coasting un neutral.

Thank you all!

Lova Andriamanjay

[mikealder]

Take a look at the ETM in the car, if its got a white sticker then its the original, replacements have a yellow sticker, quite possibly two faults though the antenna ring is worth changing - usually when these start to play up the car will fire up for around one second then die, I have never had mine cause miss fire and the ring was shot until I changed it!

The ETM is known to be a weak point with these cars, I had to change mine nearly a year ago engine RPM all over the place and cutting out as you stopped at junctions, since getting it re-manufactured by bba its been fine, the other option for a better longer term solution is the XeMoDeX contactless version - Mike