Hesitant @1500RPM and P0340

nickgb

A few months ago my wife phoned me from the local supermarket - the car had pretty much come to a stop exiting the motorway and she had limped into a car park. The engine was misfiring badly as soon as it warmed up. Replacing the coil pack seemed to fix the problem and we were back on the road a day later.
Two days later the report from the boss was "the car didn't feel right", and the warning light on again. The code was easily read it is P0340 - defective cam shaft sensor - but not very useful, all the information I have says the Z22SE does not have a cam shaft sensor. It took me three days driving to feel the problem - below about 1600RPM (but sometimes up to 2000RPM) there is a misfire when opening up the throttle.
It feels to me as through the mixture is too lean when accelerating so the EGR valve (very rusty in an 8 year old car) was the next replacement although it did not explain the P0340. It did not make any difference I still have the problem and I still have the P0340 engine fault code.

Any suggestions? Where do I look next?

MikeS

could well be a lazy front lambda sensor as for the misfire

vocky

might be a duff plug or injector

nickgb

New plugs have fixed the most obvious problem, the misfire at low RPM (thanks to Vocky). No visible reason why the old ones were failing, all looked clean and in good condition, but after a new set the engine settled down - not immediately but after a week on the road.

I still have the P0340 engine code though, it is very persistent. It often logs at very low speed (often <10 mph) and low RPM (<1500) shortly after starting the engine. I can reset the code and drive the car for hours with nothing then drive it for only a couple of minutes and the code is back.

Can anyone tell me what the P0340 code means in an engine with no cam shaft sensor?

sdbutler10

sounds alot like ine mate, mine missfires when the engine is cold, and hesitates bwtween 1500 to 2000rpm a sort of miss fire there as well.