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Hi, I've been having alot of trouble with an erratic idle problem that regularly causes the car to stall. As soon as there is any amount of throttle on the car it runs completely fine but just refuses to idle. I've replaced all the coils and plugs, new oxygen sensor and new MAP sensor. I cleaned the throttle body yesterday as there was quite alot of oil residue but still no better. Any ideas?

Hi Josh
Have you replaced the Air Filter ?
I am not saying that would cause your problem but a good starting point perhaps.

Also it would help any suggestions if we know exactly what engine Type/Code your car is.

Have you checked all intake/throttle body hoses and pipes for vacuum leaks?
Does the car start alright, battery fully charged and at good health?

Could be caused by a fuel system problem. When was the last time the fuel filter was renewed as it could be clogged. Perhaps it might be worth checking out the injectors and giving them a test and a clean they might be blocked. Even the fuel pump or fuel lines could be faulty or clogged/restricted.

Other checks which might be worth doing for fault finding is cylinder compression test, engine timing, timing belt tensioning.

This sounds like it could be the rather nasty 1.2 timing chain issue. RUM should comment on this soon

Air filter was recently replaced and doesn't look like it would be causing any problems. I've had a look at the the vacuum hoses and pipes and can't see any obvious signs of any leaks but not entirely sure how to check thoroughly. I had considered a problem with the fuel system but I replaced the filter about 3 months ago and due to the problem being completely solved as soon as any throttle is applied I figured it was unlikely. Over the past few days It's been getting harder to start but I'm not sure why, thought it might be due to having had to restart it that many times when it stalls over the past few weeks it could be wearing down the starter motor.

alexperkins wrote: Wed Feb 20, 2019 11:46 am This sounds like it could be the rather nasty 1.2 timing chain issue. RUM should comment on this soon

I agree, that needs to be checked and proved/disproved before spending more money on other things, check or get checked, the static timing to see if the chain has stretched too much or the chain has jumped on the chainwheel.