I had a turbo charge tube boot explode while towing a car going up hill. I replaced the boot now I have a service engine light that blinks only when the transmission shifts out of overdrive and the rpm goes high. As soon as the rpm drops the light stays off. It doesn't feel like it's missing. I put in new valve cover gaskets/under cover harnesses last fall when I replaced the glow plugs. Could I be getting an overboost now causing this? I am on a trip so haven't been able to find anyone that can check for codes. The truck has 345000 miles. I now live in Las Vegas.

 

It could be overboost, but the only way to know for sure is to hook it up and read the codes Do you have a tuner/chip installed?

 

It has an old Superchip programmer. One that has only one power setting.

 

If the light goes out its most likely an over boost. The RPM's go up then drop so boost goes down.

 

It doesn't stay on steady, just blinks until the rpm drops. It doesn't do it unless I'm towing up a hill and the tranny downshifts and the rpm goes near or above 3000. I seldom tow but was towing a car on a car hauler this time going thru the mountains west of Vegas going toward LA.

 

Behavior of an overboost code: The SES light comes on as soon as the overboost event occurs, then the light stays on for about 90 seconds. If the SES light flashes and goes out immediately, something else is going on. Since a chip is involved, ICP is one of the possibilities.

 

I will try to get the codes read in the next couple days and see what is going on.

 

ICP would be my guess