CEL Help

[ant]

Hi all. Just wanted to put this out there and see what people thought. Lately my CEL (Check Engine Light) has been flashing on for a very short time. 95% of the time it comes on at exactly the same spot every day, and usually its when Im holding steady pace or accelerating slightly up a hill. It literally flashes on for a second then goes away. After every drive when the light comes on I check for codes but always 5 slow 5 fast which is no codes logged. There has only ever been one code and I dont know if its related but it was 7 slow 3 fast which is injector pump communication. I had a work shop also scan for codes but nothing. The only things that changed on the car before the light started was I replaced the rear muffler with a straight through pipe (full beaudesert exhaust, now with no muffler) and I did the EGR/vacuum hose mod. Anyone got any ideas, or even somewhere to start looking? Just thought id see what everyones thoughts are.

 

[Old.Tony]

If it were me, I'd start where things were showing intermittent difficulties before and pay close attention to the electrical connections for injectors, fuel pump, any sensors on the fuel line and your MAPS too. There's also value in removing fuses and re-inserting them (it cleans the contacts) but beware that some fuses will cause the ECU to lose power and that will wipe your tripmeter and may require you to re-enter the radio pin.