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idle dropping /going lean at idle

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Old 01-01-2015, 11:10 AM
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col93saphcos
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Default idle dropping /going lean at idle

Hi guys,
93 plate 4x4 idles shite,
Revs drop and come back up again, afr going lean to normal,
Did check from ecu and all seemed in tolerance,
Tps and iscv disconnected idles fine but so does unplug lambda,
Cts relatively new, lambda also,
Tps 0.15v at idle,
Fuel pump 13 odd volts,
Base idle 950 rpm,
That's months it's been shite any ideas?
Last effort to get it right, totally sick of it and now my pishy bayjoo springs are broken, Ffs!
CheeRs Colin

Last edited by col93saphcos; 01-01-2015 at 11:12 AM. Reason: add info
Old 02-01-2015, 12:53 PM
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carl/saff
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base co been set at 950 rpm .. ?

I always clean the idle screw (counting the turns)- remove- clean -refit and use mate co testing maching ..
Old 02-01-2015, 03:09 PM
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James @ M Developments.
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We can tweak the map and add some fuel at idle and adjust the closed loop strategy if you want us to try. just send the chip in with some figures of what you get and lets see if we can help.
Old 02-01-2015, 06:40 PM
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col93saphcos
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Thanks James,
Think maybe got it this time,
Lambda sensor I think, swapped it with narrow band output from afr thing, and seemed fine,
If snows will go for test drive, if not will try it out tomorrow,
Will the narrow band output be ok or best to renew lambda sensor it's the standard one fitted in turbo exhaust housing,
CheeRs Colin
Old 02-01-2015, 07:23 PM
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col93saphcos
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Ah well not the lambda sensor then,still crap
Old 03-01-2015, 02:11 PM
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leaky FPR?
Old 03-01-2015, 02:34 PM
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col93saphcos
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Doesn't seem to be tried a couple now

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Old 03-01-2015, 06:03 PM
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Reading over bigturbo pages , L8 will try and still run the engine with faulty phase sensor and map sensor. Maybe your pipe is split or faulty sensor. L8 must be much harder to diagnose issues than L6 as they just stop running instead of 'bypassing' sometimes.
Old 04-01-2015, 09:35 AM
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I have same problem in my L8 ECU...idle dropping up and down at cold engine.... I cant find an solution ....big nightmare
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