You guys helped through an ICP swap recently, the help was greatly appreciated. I'm now having another issue I'd like some opinions on.

After the ICP swap, the truck ran rough when cold. Seemed an obvious injector issue. I bought and used the starter 2-bottle kit of Rev X and the issues magically disappeared. For the first time in my life I believed in snake oil, this one certainly did what was promised.

Fast forward 2 months and I'm back to running rough. I have put no more than 3K miles on the new oil change. The weather is getting colder, but I'm in central FL so most mornings are still in the 60's.

First start in the morning, it runs EXTREMELY rough shaking the truck for about 10 seconds. It smooths out then but unless it is up to full temp (idle for ~10 minutes) it runs rough driving out of the neighborhood. Once it is up to full temp it runs perfect.

Where to go next?
- injector test from a mechanic?
- add more Rev X and keep truckin?
- Use thinner oil (I've read 5W40 helps, I used Motocraft 15W40)
- Can injectors be cleaned/rebuilt?

thanks for any advice/info.

 

I would suggest checking the FICM voltage and check for any trouble codes. Also, some people have reported better cold starts with synthetic 5w40.

 

I have a copy of the TSB 08-26-3 which details the FICM test and the expected results. It is part of an Alliant Power tech bulletin APTB-01/09 R1. It looks to be pretty thorough. It is breaking new ground for me to do a test like this. What test equipment would I require, or is there a simple pin to pin test for FICM voltage?

There are also currently no codes being thrown from the ECM.

 

Second thread down from the top of the list is the .......TECH FOLDER...... The FICM testing procedure is listed in there.

 

FICM testing showed 20V while trying to crank. The engine had been cranking prior to this test but at this test, it had given up.

The repair procedure as DrQuad described in the tech folder fixed everything. I can't believe how easy it was with the info I found here. I owe everyone a beer.

thanks
Brian