Alright so about 2 years ago i put in a cold air intake that i modified from a dodge ram and took out the old steel rusty crankcase breather and tube and put in a chrome filter. Ever since then my check engine light has come on. Now i have a 3.9L in the truck, i ran the light with my scanner and it came up with a cylinder 7 misfire, how can this be??

Any help would be greatly apprecieated ,
Thank you

 

so let me get this straight, you've been driving your truck around for 2 YEARS with the MIL lit, and your just starting to worry about it now? thats your first problem. your second problem is that you say you have a 3.9 v-6... with a cyl. #7 misfire code. last time i checked, the "6" in "v-6" means... 6 cylinders. with that said, there is absolutely no way that a cold air intake setup, (or a crankcase breather for that matter), would make the pcm throw a #7 misfire code. so in short, your cold air kit has nothing at all to do with your MIL. and it sounds to me like your running a v8 pcm in a v6 truck. if this is the case, perhaps your getting a #7 misfire BECAUSE THERE IS NO CYL. #7!!!! i would correct that before you do anything else.

 

I think he was saying that he just dropped in a 3.9 from what I understand???

 

Ya know i asked for advice no to patronized, i KNOW what the "6" stands for in v-6. it was just simple question.

 

Well are you running a V8 computer? Or did you switch your pcm down the the V6 one?

 

either way, i would hope that people have a little more common sense to post a question like yours on a forum... at its most basic element, it still comes down to the fact that you have a 6 cylinder engine, and your asking about a #7 misfire. doesnt make any sense at all.

 

You need t be more specific in your post. To me it seems like you put a v6 in.

 

As I read this, it sounds like the OP is as perplexed as anyone else about a Cylinder 7 misfire on a V6. See the red text in the quote above. I think the question he was asking is why is there a cylinder 7 misfire on a v6.

 

im not trying to belittle anyone, but if he was previously running a v8, with a v8 ecu, then went down to a v6, but never swapped ecu's, the answer should be VERY obvious. thats what i was getting at.