08 V6 stumbles on start

[Pony08]

This seems to have started back in august after I had the Ford dealership install my CAI (to keep the warranty intact). Sometimes when the car has been sitting (anywhere from overnight to a week or two) when I go to start it, the engine starts but begins to rumble and shake for a few seconds then dies. After it does this, when I try to start it again, it starts up just fine. There are no problems starting it when the engine is warm, and it doesn't do this all time when the engine is cold. Outdoor temperature doesn't seem to make a difference but I haven't really paid attention too much. It just has a hard time starting sometimes.

PS. I have had success in starting it the first time just by holding the key in start while it rumbles slowly to life. It just takes a few seconds. Also, after it dies the check engine light is on. After I noticed this, I tried to read any codes that may have been thrown but none were present. When I started the engine right after no lights were present on the dash.

[Quick281]

did you get a tune for the CAI ?

[Pony08]

Originally Posted by Quick281

did you get a tune for the CAI ?

Yes, it's tuned with the Ford Racing tune that came with the CAI.

[matt07gt]

Is the CAI on tight? MAF?

[Pony08]

Originally Posted by matt07gt

Is the CAI on tight? MAF?

Yeah everything seems tight. A dirty MAF is a possibility, should I take it to the dealership? I don't want to risk screwing my warranty so I'd rather just have them look at it. At first I thought fuel pump because it could be a symptom of no fuel pressure when it sits but it started happening after I got the CAI. I hesitated taking it to the dealer because it doesn't do it all the time and only after it sits so I doubht they'd be able to recreate it.

[Quick281]

Originally Posted by Pony08

Yeah everything seems tight. A dirty MAF is a possibility, should I take it to the dealership? I don't want to risk screwing my warranty so I'd rather just have them look at it. At first I thought fuel pump because it could be a symptom of no fuel pressure when it sits but it started happening after I got the CAI. I hesitated taking it to the dealer because it doesn't do it all the time and only after it sits so I doubht they'd be able to recreate it.

could have a cracked coil. ford coils love to do that

[rw0640]

mine just started doing this now that its colder. it only does this when it has sat overnight. I have a cai with a tune also. Mine will start if I hold it and let it slowly rumble to. I was thinking of trying to flash it back to stock for the winter, I don't know if that'll help though.

[Wicked Xtreme]

Sounds like a tune problem to me. Have the Stealership look at it since they did the work.

Good luck

[rw0640]

I tried flashing back to stock... no luck, now I have a check engine light.

[1990_LX]

Did you check the MAF yet?

[Quick281]

cant run a stock tune with a CAI

[rw0640]

Originally Posted by Quick281

cant run a stock tune with a CAI

yea, it runs too lean. the tune wasnt the problem in my case. I replaced my battery and havent had any problems. Maybe check yours, I know on an 08 it should be fine but you never know.

[Quick281]

i put a stock tune in my stang and it actually started...

[rw0640]

Did you figure it out? Thought the battery helped, but its happening again. it takes about 3-5 times to get it started. I don't know maybe its the alternator.

[sking]

Originally Posted by rw0640

Did you figure it out? Thought the battery helped, but its happening again. it takes about 3-5 times to get it started. I don't know maybe its the alternator.

+1 Very interested if you were able to resolve the issue. I purchased a ford racing cai kit with tuner for my car last month. I have not installed it yet since my car is in storage now. I hope there is not a issue with the ford racing tune.