Hi all,

Just wondering if anyone can shed some light, i've got a 98 puma with a terrible idle, revs all over, sometimes it cuts out.

I have had ECU reset, drove, then codes read, only one it found is Cam position sensor, which was replaced but bad idle still present.

I have cleaned the idle control valve (twice) with a full can of carb cleaner, and also cleaned MAF. When i unplug the idle conrol valve the car wont tick over at all, so I guess the ISCV is doing its job.
I've also checked the plug for the power steering pressure sensor and also the microswitch on top of the clutch pedal, as i've been told theyre a weak point on these and can cause random running issues.

When the car is first started in the morning, it will idle fine for the first few mins. Revs are at about 1200 rpm at this point as its on cold start. as soon as it comes off cold start/choke, the idle goes bad again.
Is there some sort of sensor that the car doesnt read until its 'off choke'.

Also, sometimes when sitting stationary, in neutral with foot off clutch, the revs will creep up to about 1500rpm, the only way i can get the revs to drop is to press the clutch and release it again (still in neutral), then revs drop to about 800-900, but go really lumpy again.

Any ideas folks, its doing my head in...
any help greatly appreciated.

 

I would clean your idle speed control valve out. Or even get another one and change it. It should be on your inlet manifold near throttle body.

 

Might be the flap in throttle body as had issues with some fords and a lot of vauxhalls.Builds up carbon deposits on edge. As far as i mind it says on the body not to clean them but never had any probs.

 

ISCV, sometimes they respond to cleaning, but more often than not just replace. £25 from ebay.