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Idle Problem

675 Views 9 Replies 7 Participants Last post by  bert
From having a steady idle of 900rpm, It has suddenly gone to 1800rpm and I havent done anything
When I disconnect the Throttle position sensor (the one that I have connected the resistor to) nothing happens it remains at 1800rpm, I dont understand why this has just happened....... Any ideas?
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throttle body wedged open some how ???
You have developed a vacuum leak. check for blown off hoses/leaking couplers!
sounds like a vac leak.
I get this on mine though it jumps exactly the same amount.. I can cure it with the idle screw.. then a few weeks later it jumps the other way again.
Stick a timing light on the crank and check you are getting the same as what the megasquirt says.
That will rule out a timing issue i.e. borked cas or worn key way.
Checked all the vac hoses and hoses from the SC and I/C they all seem fine, will check the timing tomorrow when I get my timing gun back. I will keep at it..........
Cheers Guys
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Clean your TB and ISCV, etc!
Found it!! The bung cover thingy that is used for Cruise Control (right at the back of the inlet manifold, low down) had blown off (Thanks Richy), idling nice now
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Top result, sounds like you managed to resist the temptation to play with your ems settings which in these circumstances is just too easy to do.

Glad you got it sorted.
Phew! Well done matey.
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