Looking for a sanity check/opinions.
Truck is a 98 3500 dually cab and chassis box truck. 5.7 gas Vortec. Crate motor installed by/for PO. Already had the crank sensor die.
Muffler replaced Monday due to a broken baffle and a god awful racket it made.
We went through Nashville at a slow crawl due to traffic, constantly shifting from 1-2-3. So, pretty much, hot conditions for any engine.
Pulled into a station for gas right after the city. Truck wouldn't start after sitting for 10min or so while we were inside, wouldn't hit at all. CEL was now lit.
Pulled codes, only had P0404 exhaust gas recirculation control circuit range/performance.
Searched about the code for 10min or so. Truck then cranked and idled rough. Drove to parts store, installed a new EGR, one contact in the plug had some light corrosion. It was the 5V reference pin. Gave it some contact cleaner. Checked voltage, got 5.1V.
No heavy carbon deposits.
She fired right up with a smooth idle.
Here's my hypothesis: EGR valve was marginal, increased back pressure from new muffler combined with the heat of an hour of stop and go pushed it over the edge. After cooling a little while, it started working again or truck went into a limp mode.
Code was erased before we started driving again, CEL did not light after 5 hours of hard driving. Haven't checked codes, tired, will check tomorrow before we leave hotel.
Anything I should check or be looking for? Is my reasoning sound?
Truck is a 98 3500 dually cab and chassis box truck. 5.7 gas Vortec. Crate motor installed by/for PO. Already had the crank sensor die.
Muffler replaced Monday due to a broken baffle and a god awful racket it made.
We went through Nashville at a slow crawl due to traffic, constantly shifting from 1-2-3. So, pretty much, hot conditions for any engine.
Pulled into a station for gas right after the city. Truck wouldn't start after sitting for 10min or so while we were inside, wouldn't hit at all. CEL was now lit.
Pulled codes, only had P0404 exhaust gas recirculation control circuit range/performance.
Searched about the code for 10min or so. Truck then cranked and idled rough. Drove to parts store, installed a new EGR, one contact in the plug had some light corrosion. It was the 5V reference pin. Gave it some contact cleaner. Checked voltage, got 5.1V.
No heavy carbon deposits.
She fired right up with a smooth idle.
Here's my hypothesis: EGR valve was marginal, increased back pressure from new muffler combined with the heat of an hour of stop and go pushed it over the edge. After cooling a little while, it started working again or truck went into a limp mode.
Code was erased before we started driving again, CEL did not light after 5 hours of hard driving. Haven't checked codes, tired, will check tomorrow before we leave hotel.
Anything I should check or be looking for? Is my reasoning sound?
