Annoying lean spike help please:
Annoying lean spike help please: Here is the deal:
In 1600 and 2000 rpm colums only, at less than 15% throttle only I get an annoying lean spike every 5.5 seconds. Any gear, any road speed. Every 5.5 seconds. I have OLSD tune so there is no MAF to worry about, nor stock O2s failing. It feels like the car hits a rev-limiter for one instant, spikes lean and then goes a bit rich and then settles back in line. For 5.5 seconds. Sure makes cruising around corners interesting with the Locker
.
What the Hell is that? I can find nothing in the fuel control that happens at less than 15% throttle or every 5.5 seconds.
The only thing that happens is the spark advance drops to almost 0 every time it happened.
In 1600 and 2000 rpm colums only, at less than 15% throttle only I get an annoying lean spike every 5.5 seconds. Any gear, any road speed. Every 5.5 seconds. I have OLSD tune so there is no MAF to worry about, nor stock O2s failing. It feels like the car hits a rev-limiter for one instant, spikes lean and then goes a bit rich and then settles back in line. For 5.5 seconds. Sure makes cruising around corners interesting with the Locker
.What the Hell is that? I can find nothing in the fuel control that happens at less than 15% throttle or every 5.5 seconds.
The only thing that happens is the spark advance drops to almost 0 every time it happened.
Last edited by 1CAMWNDR; Mar 10, 2008 at 04:59 PM.
Spark and fuel cut together is the signature of DFCO.
Maybe the car gets enough of a whiff of "deceleration"
to kick that in. Try disabling DFCO entirely and see if it
quits the behavior. If so then the next question is,
what accounts for triggering it rhythmically?
Maybe the car gets enough of a whiff of "deceleration"
to kick that in. Try disabling DFCO entirely and see if it
quits the behavior. If so then the next question is,
what accounts for triggering it rhythmically?
I was wondering about the DFCO also, but can't understand it going into DFCO every 5.5-6 seconds. Good idea to just disable it and see what happens.....
OK. Disabled DFCO and the problem has fanished. I reset the entry TP% up to 20% instead of the 15% it was at
. We will see if that fixes the cruise lean spike/stumble. I think it should.
. We will see if that fixes the cruise lean spike/stumble. I think it should. Trending Topics
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Verdad Gallardo It is better, but I agree that 10% should work better. It rarely goes down to 10% with the cruise control on. Now I just need to get the kPa fixed so it still works at cruise so I can save more gas
.
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Why do you have your DFCO throttle setting so high?
You should be able to lower it back again if you play with your MAP, RPM, and VSS settings. I have mine to come in [way] under about 5% and it never comes on when I don't want it to.
You should be able to lower it back again if you play with your MAP, RPM, and VSS settings. I have mine to come in [way] under about 5% and it never comes on when I don't want it to.