I have been having trouble with my L at the track not running as good as I felt it should. It even threw a code that was caused by powerbraking the motor to 100% throttle (I haven't done that), high inlet air temp, or high trans temp. I checked over the whole truck and nothing really seemed wrong. One thing that bothered me was the intercooler fill tank was overfilled so I decided to drain a bit and watch how fast the refill rate was with the pump running. Started the truck, disconnected the hose but no fluid movement. I checked the pump and it wasn't running, I wiggled the connector and it would run for a second or two then stop. I did a voltage check at the plug after checking the fuse and relay and there was 14.15 volts at idle. Disconnected the hose at the pump and hooked the pump directly to the battery, pump would sing but still no fluid movement.

I am guessing part of the impeller has come apart or completely fell off, whatever the case my new engine has been injesting some really hot air over the last month and running like crap because of it. I will be ordering a new intercooler pump tomorrow and having it installed Turesday under warranty, will post results from the track visit Wednesday night soon after! Hopefully I'll have my top end 40 hp back and be able to run a bit quicker than 14.20 @ 95mph!!

 

Good news! Let us know the outcome . . .

 

The pump does not come on all the time. It's controlled by the PCM to come on and off based on ACT2 temperature readings. Let the truck idle for about 5 minutes to warm up if it's cold and it should be pumping.

 

John,
good detective work, hope that FINALLY solves all your nightmares.......JR