Author Topic: idle problems  (Read 1577 times)

Offline carloscdt

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idle problems
« on: 06 January 2005, 13:05 »
think i've caught something about this before but here goes...
Mk2 1987 8V  PB engine - Digifant -
Car keeps reving +/- 500 RPM about the idle speed and
very often cuts out as the revs drop.

Is this the ISV thing?

Cheers

Offline Gambit

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Re: idle problems
« Reply #1 on: 06 January 2005, 13:39 »
courtesy of http://www.gvk-motorsport.co.uk/

1. start engine. When at normal operating temp, disconnect BLUE
plug from water pipe on front of cylinder head. Rev engine PAST
3000RPM 3 TIMES. (This resets the ECU).

2. Alter the idle using the screw in the throttle body. Set it to
850/900 RPM. When happy, re-connect the blue plug.

It should now be OK. If it is not, then you may have a fault on the
blue sender

The senders are very cheap (?13ish) and are worth replacing if you have any kind of over-fuelling or idling issues with your 8V

Also, the rubber grommet on the rocker cover where the breather fits can sometimes split causing a major air leak - check this and look around for any other vacumn leaks whilst you're there
Remove the brass idle screw and clean the end,a lot of Digifant idling issues can be simply rectified by cleaning the screw
Many people think "Aghhhhh, I need a new ISCV (idle speed control valve) ?????? - try the set up first and check the wiring to (and) the microswitches on the throttle housing before spending your hard earned cash on a new ISCV

Offline Mr Blue

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Re: idle problems
« Reply #2 on: 07 January 2005, 10:17 »
Gambit,

whats the blue sensor and the other one for by the way?
:)

Offline Gambit

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Re: idle problems
« Reply #3 on: 07 January 2005, 12:37 »
blue is for the ECU
black is just your water temp gauge