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Cruising up to a red light tonight, had the gears in neutral, foot off brake & off accelerator, when the engine suddenly redlined on its own!

I quickly put my foot on the brake which instantly dropped the revs. This make me think something funny happened with the cruise control...thinking it needed to accelerate until the brake activation provided the cut out.

Has anyone else had this problem? Possible reasons other than cruise control gone glitchy?

I should mention this is the first time my baby has seen the redline...I dont know who was more surprised, me or her!

Quick thinking to suspect cruise control and hit brakes switch off function. Can you pull a cruise control fuse to isolate it so not happen again until fixed ?

So you were driving along with your cruise control on and just knocked the gearshifter out of gear?

The cruise control has switches on the clutch and brake pedals, so that if either one is depressed the cruise control will be deactivated. I'm also thinking (but not 100% sure) there is also a neutral switch on the gearbox, which should also stop the cruise control.

Cruise control hadn't been on, I'd been driving with my right foot then slipped it into neutral when the light went red & was coasting when after about 10 sec it redlined out of the blue!

I had slipped it out of gear without the clutch (lazy lol, just revmatched), but the CC hadnt been on so that shouldnt matter.

Really can't see the CC pulling on the throttle if it wasn't turned on. I'd be checking that your idle air control valve is clean, sounds like that may have opened. So did the engine start screaming? and did any lights on the dash come on?

yep, engine suddenly screamed to the redline with no warning. No dash lights, just the tacho @6500

I'll have a look at the idle air control valve, is there any trick to inspecting it? Is that the one you shouldnt remove cos its almost impossible to reset correctly?

So you could actually hear the engine screaming? I'm only asking becasue I was thinking just the tacho had a electricial spike and sent it crazy.

If your throttle is closed the only other thing that lets air into the engine is the Idle Air Control Valve. Pretty sure from memory the early EJ20 Foz had the IACV on top of the throttle body. You can remove it (I think with 2 screws??) and clean it out with some carby clean spray. I'd also replace the little rubber gasket/seal when you take it off. Might be best to buy a seal beforehand.

Also check that your air filter is clean

Did you get to the bottom of this Matt?

Cheers

Bennie

Nope. Checked all the nuts, bolts, hose connections, all good. I have to get an IAC gasket so I can do what Paul said & take it off for a clean. Hasnt happened again....touch wood lol

PS: have got a slice of wood from Bullocks Link Tr on the dash for just this purpose