Ok, I have read everything I can find about startup issues on here but it seems that everyone has problems with warm starts. My 05 5.4 Lariat has a cold start problem. After sitting for at least 5 hours when I start it, it misses for about 3-5 seconds then smooths right out?? I haven't got any check engine lights but it is now a consistent issue. I can start it all day after the first time and it will start fine all day long.

I just finished my Magnacharger install and replaced all plugs and injectors so I would hope I could rule those out.

Once it smooths out the vacuum pressure is rock solid. I also have steady fuel pressure as well.



Anyone have any ideas.....

 

Anyone??

 

If its throwing a P2106 diagnostic code you might want to just go have your PCM recalibrated. Check out the TSB's for our trucks.

 

Yea, I believe that my truck has the warm start problem also. Ima take mine in for service before the warranty runs out.

 

I'm thinking lash adjuster(s)/lifter(s). What I think is happening is one or more of your lash adjusters is leaking down causing your valve timing on one or more cylinders to be incorrect until it "pumps" back up and works as designed. This problem would probably not set a code.

 

It is not throwing any codes, the dealership hooked it up to the scanner today and they said it came up clean as a whistle.

The only time it seems to do it is when is gets colder. When it was 35 here the other morning it chugged like it was flooded for about 3-5 seconds. This morning it was about 50 and it didn't really do it to bad.

Could it possibly be the tune?

 

Same issue with my 07. I start up in the morning, back out of the drive and take off down the block. If I get on it, it will pop and run crappy for about one block. Then it finally smooths out. It feels like an old cold carbureted car that wasnt warmed up.

I had it in twice and they couldnt duplicate the problem. I can get over the morning thing but I worry about pulling out in traffic and having it die on me.

 

Same problem here, I have had it to the dealership at least three times and I think they are beginning to think I am crazy.