[devilxc]

While in queuing traffic, and by queuing I mean 2 hours or more, the revs on my ZS180 begin to build. The idle starts at the normal 750 and slowly goes to 1000, 1250, 1500, 2000, 3000 and all the way to idleing at 5000rpm!

The problem first happened in enroute to Germany when I was stuck in traffic for 2 hours going under Brussels. It then happened again when queuing for Rock am Ring festival. Both times were hot days and i thought it was an issue with temperature.

I have since cleaned out the throttle body as suggested here
http://forums.mg-rover.org/showthread.php?p=3847403
I have also tried cleaning around the IAC as suggested here
http://forums.mg-rover.org/showthread.php?t=279797

I thought I'd fixed it but yesterday it happened again; when the snow (in Leeds) caused my 20min drive into a 4.5 hour epic. I had to dump the car (due to the over reving) after 2 hours and get a lift the rest of the way. This removes the likelihood of overheating as the temp was sub zero.

Any suggestions?

My inlet manifold sounds like a bag of spanners but I'm guessing that won't be related at all?

Thanks in advance.

 

[RaptorUK]

Did you take your idle control valve off and clean it inside with carb cleaner ?

You should also check that your throttle cable isn't being caught up on something or otherwise restricted . . . it's what caused my problem.

 

[devilxc]

Yeah IAC / ICV gave it a good clean with carb cleaner. Not had a look at throttle cable as the car is fine 99% of the time. The issue only shows up once I've been queuing in traffic for about 2 hours.

 

[Spectre]

Yeah IAC / ICV gave it a good clean with carb cleaner. Not had a look at throttle cable as the car is fine 99% of the time. The issue only shows up once I've been queuing in traffic for about 2 hours.

I had a sticky idle that was a worn plastic part on the throttle spindle, it was worn at an angle and would twist in a way it was not supposed to, this would then bind the throttle cam on the way back to closed causing the throttle to stay open. I fitted a brand new throttle body form ebay for £70 and now religiously lubricate it to stop it wearing again (incedently the new items have a different type of plastic).

 

[devilxc]

I had a sticky idle that was a worn plastic part on the throttle spindle, it was worn at an angle and would twist in a way it was not supposed to, this would then bind the throttle cam on the way back to closed causing the throttle to stay open. I fitted a brand new throttle body form ebay for £70 and now religiously lubricate it to stop it wearing again (incedently the new items have a different type of plastic).

Thanks I'll give it a look.

What symptoms did yours have? Mine returns to normal if I leave the car turned off for an hour or so.