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Discussion Starter #1
ok, so here’s my issue. i’ve got an 08 lmm that i bought used that’s been “heavily modified” and as i drive down the road and get into the pedal a little to either accelerate or even just to maintain speed, the glow plug light will come on. sometimes it’ll go off on its own, but more often than not i have to let up just a tad on the pedal to get it to go off. this is even when going pretty easy on the pedal.

not 100% sure on all the modifications, but i do know for sure it has a ppe dual fueler, a dsp5 switch, and a few of the tunes throw quite a bit of black smoke at as little as 1/3rd pedal, indicating to me a lot of fuel is being dumped in there. also, from what i was told by the dealer who had supposedly bought it from the original owner who’d done all the modifications, it also has bigger injectors, a bigger turbo, and the cam and crank are both keyed, but i haven’t been able to verify those claims yet other than it does scoot along pretty quickly. it also does have a torque convertor locker as well that i‘ve dont usebut did accidentally lock up in park in the driveway once while dicking around with it trying to figure out what it does....that was my bad.

so far a few of my thought as to what may be wrong are: 1) it’s dumping a sh*t ton of fuel in there and cooling the cylinders to the point the glow plugs are kicking on, maybe by a sticking injector or just from fueling that heavy in the tunes? 2)maybe the glow plug controller is going out and causing the light to come on intermittently. 3) bad tuning that causes the light to come on? and that’s all i’ve got so far.

sorry for the long post, but i’m interested in any input anyone may have. thanks
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