KB 2.8 idle question???

NIL8U

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Im new to the mod motor and about to purchase a 03 cobra with a 2.8 KB non mammoth. I had a question regarding idle. it seems to have a small misfire at idle, is it common with these KB 2.8? or could it be tune, plugs, coils?

I know its kinda vague info but i am about to go see and test drive it within the next couple of days.
any help would be greatly appreciatedladies and gents.

Reposted here seems a lot more active.
 

03' White Snake

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That's not normal. Mine idled like stock with stock motor. Check plugs, vac leaks. Boost bypass is working, and or could be the tune. What injectors are you running?

Even with the built motor and cams, mine still idles just fine, no missing.
 

NIL8U

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60lbs injectors
Dam, that sucks if it’s a misfire!
It’s just at idle, you hear it run smooth then like a really small stutter.
Ive been searching and it ranges from plugs ngktr6 most common that do it to coils and internal engine problems.
What if it drives normal and just does it at idle?
I will be test driving it soon as it’s a couple of states away
 

Quick Strike

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Try to avoid buying someone else's troubles if you can. Mine is similarly smooth even with cams. I would wonder why the seller did not address this if selling. Or, did he?
 

CobraBob

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I agree with @Quick Strike. NO way would I proceed with a buy on that car without the issue having been corrected. Just not worth the risk of it ending up to be one of multiple issues. Could be plugs. Then again, it could be something else. Do you really want to spend more time than you want to trying to find/correct the issue if you purchase the car "as is"?

Sometimes finding out about one seemingly small issue on a car you're looking at ends up being a subtle warning flag.
 

Stage 4.6

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Mine isnt a 2.8, but i do have the 2.6H and had a slight miss only at idle, other than that it ran fine. The issue was in the tune. Before i even went to E85, i had my car re-tuned with HP tuners (91 oct) and installed ID 1050x, car idled and ran great.
 

GodStang

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Ya I would guess tune. I have run 4 different KB all different sizes and never had a miss.
 

NIL8U

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Thanks gents for chiming in, didn’t buy the car after all flew over 1,000 to see a car with a cracked rocker bumper paint bubbling. So I m going back home empty handed.
 

Stage 4.6

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That sucks! hate when people don't disclose those type of details. Good thing you went and seen it personally. Keep searching the right one will come around.
 

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