Ls1 goes lean at idle
Thread Starter
On The Tree
Joined: Aug 2009
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Ls1 goes lean at idle While at idle the afrs go from 14 to 18 on my wideband which creates a hesitation and a rough idle then the o2s must pick this up and returns to 14.2 and the idle clears up.Also every now and then the car once its warm hesitates and splutters for a short moment while cruising at low speeds and wants to buck when in first gear.Wot its perfect.With my obd11 there indicates no missfire,and the o2 sensors seem fine,anyone possibly no whether this is tune related. Its driving me crazy
Thanks
Thanks
WOT & normal driving are basically different tunes. Idle fueling could be a number of things. Sounds like the MAF table scaling is off. Did you change the MAF without changing its' scaling? When's the last time you cleaned the little MAF sensor resistor wires?
The once warm issue could be the ECT tables, but more likely also MAF related.
The once warm issue could be the ECT tables, but more likely also MAF related.
Joined: Mar 2007
Posts: 1,151
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From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
Currently dealing with the same during initial warm-up from a cold state. It seems to be a OL to CL functionality issue. My O2 sensors are slowly switching or not at all; I am running Bosch units and looking to go to Denso or NTK replacements shortly.
It could also be a ground issue causing both O2 sensors to react slowly; as I do find it odd that they would both crap out at the same time.
It could also be a ground issue causing both O2 sensors to react slowly; as I do find it odd that they would both crap out at the same time.
Thread Starter
On The Tree
Joined: Aug 2009
Posts: 104
Likes: 0
WOT & normal driving are basically different tunes. Idle fueling could be a number of things. Sounds like the MAF table scaling is off. Did you change the MAF without changing its' scaling? When's the last time you cleaned the little MAF sensor resistor wires?
The once warm issue could be the ECT tables, but more likely also MAF related.
The once warm issue could be the ECT tables, but more likely also MAF related.
Thread Starter
On The Tree
Joined: Aug 2009
Posts: 104
Likes: 0
Ive currently unbolted the cat pipes as im thinking its leaking between the header pipes and where the cats bolt up.This could be causing the leak before the 02s.Ive checked all hoses in the engine bay and cannot find any cracks or holes.TB is very clean as well as tps.Its only started since i finished my m6 conversion.If anyone else has any ideas to where any possible leaks could be that would be a help.
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On The Tree
Joined: Aug 2009
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Ok after finally checking for vacume leaks and everything else a million times,when at cold start idle it idles mint until it gets to 70 degs once it get to that it goes lean to 18afrs then after a bit the o2s bring it back to around 14 afr and idle clears up.So this morning it was doing the same thing then i jacked the car up disconnected the o2s and now it idles perfectly and sits on 13.3-13.5 afr on the wideband.Maybe they have been turned off in the tune or are my 02s shagged?
cheers
Glenn
cheers
Glenn
Teching In
Joined: Feb 2015
Posts: 46
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From: Ny
Ok after finally checking for vacume leaks and everything else a million times,when at cold start idle it idles mint until it gets to 70 degs once it get to that it goes lean to 18afrs then after a bit the o2s bring it back to around 14 afr and idle clears up.So this morning it was doing the same thing then i jacked the car up disconnected the o2s and now it idles perfectly and sits on 13.3-13.5 afr on the wideband.Maybe they have been turned off in the tune or are my 02s shagged?
cheers
Glenn
cheers
Glenn
