This is going to be a long one, so bear with me. 2013 LR4 V8, 70k miles.
Starting last summer, I started having issues filling the truck with fuel. It was random, and was just the pump clicking off very early here and there. I noticed the fuel pump cover was leaking and replaced it (I'm going to the dealer in two weeks to have it done again under the recall). I'm not sure when exactly the fueling issues got worse, but it got to the point where I was struggling to get any fuel in the truck without it getting spit back out from below the filler neck somewhere. I replaced the DMTL pump and purge valve (based on what I was sure was causing those issues, as well as the codes the truck was throwing), and that fixed the fueling up issues.
The next issue I'm not sure when it started, but the truck would stumble and sometimes mis-shift and/or stall after filling up. I thought it was a trans issue, so I changed the fluid and filter and replaced the pan with a two-piece aftermarket one, and reset the TCU with the GAP tool. I still had the fumbling issues but the trans issue stopped happening as frequently when combined with the stumbling. This was ONLY after filing the truck with fuel, and the mis-shift would ONLY happen once. So to me, it was obviously electronic and not an issue with the transmission. It shifts fine every other time. After restarting the truck, or after that first mis-shift, the truck drove completely normal.
I dealt with this for a bit, and then it went away in the warmer weather. It started again a couple weeks ago, I got a MAF code (dont recall which) and cleaned both sensors. The truck was very hard to start one afternoon, but once it did it cleared itself up and drove normally. I got a fuel tank cap warning and replaced with an aftermarket one. That light still comes up every now and then. I cleaned the MAFs again and put in fresh air filters (it threw a MAF code) and that issue went away for a bit. Driving to work I got a reduced engine performance light.
Here are some live value shots from around that time, GAP tach in the upper right is not correct
idle
2500rpm in park
2000rpm highway cruising at 70mph
The day or so after I took those, the truck randomly stalled at a light. Restarted no problem after. I posted on another forum and was told to look for an air leak, not vacuum leak, and I heard one near the PCV valves, but couldn't feel it. But those are cheap enough so I bought them will put in tomorrow.
It's been driving fine, but this morning again I fueled up and the truck stalled out at a red light a few hundred yards down the road. I restarted it and it was still idling a little rough. No codes but the p0442 I've been getting on and off for a year. so some more values:
idle
3/4-ish throttle, pulling 3k rpm ~50-5
1700rpm or so, cruising after the pull
any ideas from the resident pros? My only idea is a saturated EVAP canister could make for a rich condition, but I'm not well versed enough in this stuff to know more than that.
Starting last summer, I started having issues filling the truck with fuel. It was random, and was just the pump clicking off very early here and there. I noticed the fuel pump cover was leaking and replaced it (I'm going to the dealer in two weeks to have it done again under the recall). I'm not sure when exactly the fueling issues got worse, but it got to the point where I was struggling to get any fuel in the truck without it getting spit back out from below the filler neck somewhere. I replaced the DMTL pump and purge valve (based on what I was sure was causing those issues, as well as the codes the truck was throwing), and that fixed the fueling up issues.
The next issue I'm not sure when it started, but the truck would stumble and sometimes mis-shift and/or stall after filling up. I thought it was a trans issue, so I changed the fluid and filter and replaced the pan with a two-piece aftermarket one, and reset the TCU with the GAP tool. I still had the fumbling issues but the trans issue stopped happening as frequently when combined with the stumbling. This was ONLY after filing the truck with fuel, and the mis-shift would ONLY happen once. So to me, it was obviously electronic and not an issue with the transmission. It shifts fine every other time. After restarting the truck, or after that first mis-shift, the truck drove completely normal.
I dealt with this for a bit, and then it went away in the warmer weather. It started again a couple weeks ago, I got a MAF code (dont recall which) and cleaned both sensors. The truck was very hard to start one afternoon, but once it did it cleared itself up and drove normally. I got a fuel tank cap warning and replaced with an aftermarket one. That light still comes up every now and then. I cleaned the MAFs again and put in fresh air filters (it threw a MAF code) and that issue went away for a bit. Driving to work I got a reduced engine performance light.
Here are some live value shots from around that time, GAP tach in the upper right is not correct
idle
2500rpm in park
2000rpm highway cruising at 70mph
The day or so after I took those, the truck randomly stalled at a light. Restarted no problem after. I posted on another forum and was told to look for an air leak, not vacuum leak, and I heard one near the PCV valves, but couldn't feel it. But those are cheap enough so I bought them will put in tomorrow.
It's been driving fine, but this morning again I fueled up and the truck stalled out at a red light a few hundred yards down the road. I restarted it and it was still idling a little rough. No codes but the p0442 I've been getting on and off for a year. so some more values:
idle
3/4-ish throttle, pulling 3k rpm ~50-5
1700rpm or so, cruising after the pull
any ideas from the resident pros? My only idea is a saturated EVAP canister could make for a rich condition, but I'm not well versed enough in this stuff to know more than that.
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