So my truck sometimes will just stop at like 50mph and wont go over 2200rpms...Any idea why? it only happens sometimes when i've got my foot the the floor. but once i let the rpms go back down it'll be fine.

 

 

Limp mode.

Welcome to the world of the Duramax Protection Program. You either limped the tranny or engine. Odds are, since you don't have a programmer yet, you didn't limp the tranny you limped the engine. This means, your fuel rail pressure was way under it's desired pressure, so the engine protects itself. Now, this can be something simple or something expensive. A lot of the times it's simply a clogged fuel filter and since you just bought it used, I'd start there. Who knows the last time it was replaced. While your at it, check and/or replace the air filter while your there. Cheap insurance. Oh, oil change and tranny service should be on the list too.

 

i agree with Rttoys, change the fuel and air filter. and at least change the tranny spin on filter. you could also go to an autoparts store and have them check for codes that may also help find the problem. hope this helps

 

change FF first, when i first got my truck from the dealer it limped on the test drive, then it took them hours to change the FF

 

I would have requested a discount for that. When a vehicle has a malfunction on a test drive, that's not a good sign.

 

Thanks guys! I think i will go down to the dealership where i bought it. The guy i go to will probably run a full systems check and what not and see what needs to be fixed or replace for free or a very small fee. I'll make sure to tell them what all ya'll have said to look for.

 

so what happened

 

oh yeah i forgot about this. So i went down to the ole dealership where i bought the truck and they changed out my fuel filter for free. which is pretty sweet cuz it would cost like 143 buck. but yeah it's fixed and is shifting fine and movin right on past 50mph with ease.

 

holy crap 143, those dealers need a

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