Intermittent lean when in boost.
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- Dreams of owning a 240!
- Posts: 66
- Joined: Thu Aug 11, 2005 7:41 pm
- Location: Sioux Falls, SD
Intermittent lean when in boost.
I've started having a problem with my KA-t intermittently leaning out at WOT. Sometimes my AFRs are perfect in the mid 11s, but then the next time I do a pull it'll be low-mid 12s, or even get into the 13s. The car runs E85, 1000cc injectors, Walbro 450 lph pump (hardwired, and brand new), a Sard FPR, and an Enthalpy tune. The car has been on its current setup for 3 years now, and this is the first issue I've had (aside from blown up transmissions ). I've already checked fuel pressure (behaves how it should), had my injectors cleaned and flow benched (they really needed it), changed spark plugs, I can't find a vacuum leak anywhere, TPS behaves properly, and the MAFS behaves properly. Anybody have any idea or suggestions?
Re: Intermittent lean when in boost.
I wonder if the fuel is heating up after the run. I have an oil cooler on my return line before getting to the tank. I do not have any issues leaning up after multiple runs. That is the only suggestion I have. Everything you stated seems spot on. After the lean WOT, if you chill for a bit then do a pull, is it good again?
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
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13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
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- Dreams of owning a 240!
- Posts: 66
- Joined: Thu Aug 11, 2005 7:41 pm
- Location: Sioux Falls, SD
Re: Intermittent lean when in boost.
It isn't always after multiple runs, sometimes it'll do it right after I start the car and let it warm up.
Re: Intermittent lean when in boost.
May want to check out your ecu coolant sensor. It could be on its way out.
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
-
- Dreams of owning a 240!
- Posts: 66
- Joined: Thu Aug 11, 2005 7:41 pm
- Location: Sioux Falls, SD
Re: Intermittent lean when in boost.
I assumed the ECU temp sensor was good because I replaced it and soldiered in a new pigtail a couple years ago. That's a good idea though, I'll have to check it one of these days and verify it hasn't failed again.
Re: Intermittent lean when in boost.
Maybe clean MAF as well.
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel