i put a flow master on the truck and the next day the check engine light came on and went right back out as soon as i slowed down. does anybody think it had anything to do with the installation of the exhaust. just a thought. its also a 95 so auto zone cant help me who can help other than isuzu.

Did you reset the ECU?

If you cut out the old and just put in the new high flow your ecu could be freaking out thinking you have a leak (but it is just a high flow muffler).

pull the neg battery terminal for 15-30 minutes and see what happpen.

-Ryan

I have a flowmaster 50 series. no problems at all. try resetting the ECU by disconnecting the battery for 2 minutes.