Joined
·
428 Posts
I've had this problem on my 02 L now for over a year and a half and i'm finally to the point where I am willing to ask for help to figure out why it's happening and fix it. The truck is my 2002 Lightning and the engine mods are a 6lb lower, ported Eaton, Accufab SBTB, REM air intake, JBA shorties, Magnaflow cats, full 2.5" magnaflow exhaust, LFP valve body in my trans, and tuned with an Xcal2.
The problem is when my truck is WARM and I start it up the RPMs will drop down, sometimes it'll pick back up and idle properly and other times it'll just die. When it dies I restart it and hold the RPMs up for like 30 seconds or so and it idles just fine after that. Now the weird part is when the engine is ice cold or when it's still hot and at operating temp it will start normally and it doesn't try to die. It only tries to die from a WARM start.
Now i've already gone through and tried to fix this on my own with no luck. I've tried to tackle this a few times with everything i've done being in vein. First thing I did was to try some simple routine maintenance, I cleaned my MAF sensor with contact cleaner, pulled the IAC off and vigorously cleaned it with brake cleaner, and I checked the TPS voltage which was already at .99v. None of that worked but since it was an idle problem I went ahead and replaced the IAC anyway, again no change. Second, another round of routine maintenance, the supercharger was pulled and the IC was cleaned, new set of NGK TR6 plugs gaped at .34, and new Motorcraft O2 sensors, again to my disappointment the warm start problem persisted.
After failing at fixing this over 2 rounds of attempts I came to the site and began searching the forums and I came upon a few members that seemed to have had a similar problem to what I was experiencing. Turns out the symptoms my truck was experiencing pointed to a bad or failing Fuel Pump Resistor. I even found a video on YouTube that seemed to cement my latest diagnosis. Not an easy part to find but again the search function of the forums came through for me and I was able to order one. I got around to installing it this past Sunday. After the install I drove around a bit and parked my truck in the driveway. I went back out after a couple of hours when the engine was still warm and started it up. It started and the idle dropped down and it stalled :smt013
After all that, the routine maintenance and the pump resistor, none of it has worked. I'm at my wits end here, and i'm totally out of ideas of what could be wrong. Please help, this is getting to be an annoying problem.
The problem is when my truck is WARM and I start it up the RPMs will drop down, sometimes it'll pick back up and idle properly and other times it'll just die. When it dies I restart it and hold the RPMs up for like 30 seconds or so and it idles just fine after that. Now the weird part is when the engine is ice cold or when it's still hot and at operating temp it will start normally and it doesn't try to die. It only tries to die from a WARM start.
Now i've already gone through and tried to fix this on my own with no luck. I've tried to tackle this a few times with everything i've done being in vein. First thing I did was to try some simple routine maintenance, I cleaned my MAF sensor with contact cleaner, pulled the IAC off and vigorously cleaned it with brake cleaner, and I checked the TPS voltage which was already at .99v. None of that worked but since it was an idle problem I went ahead and replaced the IAC anyway, again no change. Second, another round of routine maintenance, the supercharger was pulled and the IC was cleaned, new set of NGK TR6 plugs gaped at .34, and new Motorcraft O2 sensors, again to my disappointment the warm start problem persisted.
After failing at fixing this over 2 rounds of attempts I came to the site and began searching the forums and I came upon a few members that seemed to have had a similar problem to what I was experiencing. Turns out the symptoms my truck was experiencing pointed to a bad or failing Fuel Pump Resistor. I even found a video on YouTube that seemed to cement my latest diagnosis. Not an easy part to find but again the search function of the forums came through for me and I was able to order one. I got around to installing it this past Sunday. After the install I drove around a bit and parked my truck in the driveway. I went back out after a couple of hours when the engine was still warm and started it up. It started and the idle dropped down and it stalled :smt013
After all that, the routine maintenance and the pump resistor, none of it has worked. I'm at my wits end here, and i'm totally out of ideas of what could be wrong. Please help, this is getting to be an annoying problem.
