So lately I think that my 2008 QC 5.7 has been running a little sluggish. I bought a Superchips 3865 a few months ago and have been running the 91 tune with 93 octane. MDS is off. At first I was like wow this is much better. Truck has 35,200 miles on it.

Think something needs to be checked or is it just me getting used to the truck. Neve had a check engine light either.

Only mods are the Superchips 3865, K&N drop in, and a cat back exhaust.

 

I'd advise you to purchase the trans tune(~$40) it gives full control of the trans. Way more than what you have now.

Also, spark plugs are due every 30kmi and you should use the basic copper plugs.

 

Forgot to mention I already have purchased the trans tune. I have Sils shift schedule saved in there. I am currently running the Superchips one.

I knew plugs were due but I was hoping to hold off on those and new wires until spring. Think 35K on the plugs could make it run a little sluggish?

Was going to clean out the trottle body when I did plugs as well.

 

As long as you don't do a lot of short trips the plugs should be ok. I mainly only use my truck to run from central Florida up to my farm property in central Georgia and then play some up 'yonder. I did mine at 30k and by the way they looked, I could have gone to 50k. But short runs, heavy traffic, etc. will have them needing it at 30k.

Throttle body, IAT sensor, EGR & PCV all being fouled will make it sluggish for sure and a good cleaning at 30k I've found is needed...

 

Crap. Its pretty much only short trips for my truck which include HEAVY traffic because I work downtown in the city. Looks like i have some work to do.

There a guide anywhere for cleaning all of the things you mentioned hammer?

 

I know that mine really become sluggish in heat.. The cold though, that baby flies. It's a huge drain on the engine.

 

Sounds like my truck when the EGR went on it.

 

Its not horribly sluggish but just seems like its not running quite as good as when I first got it or when I installed the Superchips.

My buddy has the same truck and he said he cleans his out with "Sea Foam"? Anyone tried this? He said it works great.

Bad EGR huh? Howe much was that fix?

 

i did my egr its pretty easy look on http://www.rockauto.com/ for oem parts if u want to go that way its alot cheaper some times i didnt when i did mine it cost me 104$ for the valve and gasket then did the work my self

 

Sea Foam treatment is good, although I won't use it in the crankcase on the oil, but to clean out the intake system and fuel system - fine. But don't kid yourself and think dumping some Sea Foam in the intake will clean that gummed up throttle plate anywhere near as good as physically scrubbing it. It's more like a "maintain" thing if you start it when it's clean so you won't have to tear it apart and clean it as often.

EGR is about $35 at Advance Auto parts, made in USA by the same manufacturer who makes the Mopar part...