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How's My Fuel Trim Look

you need rpm, throttle position, and speed to make any sense out it!
 
Also would be good to have engine load. But that aside, I don't know how much can be said about your fuel trims because the XJ crowd doesn't seem to talk much about this kind of thing. My only comment is that the LTFT is staying mildly positive which indicates that the ECU is having to request a longer fuel injection pulse time than is prescribed by the baseline map. But the LTFT is at all not concerningly high, and small consistent trims like this are a common occurrence and shift back towards zero when weather or driving conditions change. Now if your LTFT were holding consistently at 10% or higher, then I would suggest that there may be a problem somewhere.
 
Hmmm, interesting. Sorry, I thought it was always supposed to be +-3%. Would an out-of-whack fuel trim cause the Jeep to run warm on hills? I just rebuilt the whole cooling system with OEM parts and milled the head. She stays under 210 most of the time but climbed up to maybe 220 on a few hills on an 85 degree day. Not something she used to do.
 
Hmmm, interesting. Sorry, I thought it was always supposed to be +-3%. Would an out-of-whack fuel trim cause the Jeep to run warm on hills? I just rebuilt the whole cooling system with OEM parts and milled the head. She stays under 210 most of the time but climbed up to maybe 220 on a few hills on an 85 degree day. Not something she used to do.

The fuel trims are what keep the engine running at the correct AFR. Most fuel systems are designed to accommodate situations where the actual fuel demand is as much as 15% above or below the predicted demand, i.e., up to 15% above or below the base fuel map. I consider LTFTs of +/- 7% to be normal. Anything outside of that range suggests an issue. If fuel trims exceed +/- 15%, there is definitely a significant fuel system issue.

So, your slightly positive fuel trims are not suggestive of an obvious issue. However, fuel trims are based on the behavior of all cylinders combined, and a significant fuelling or spark issue may not immediately be identified by fuel trim values alone. You should be assessing whether there is an obvious misfire condition or anything else that may suggest that a particular cylinder is not functioning properly.
 
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