after pulling my truck out of winter storage and running two tanks of premium fuel threw it it is getting smelly after sitting at idle in drive thru,s and traffic lights no codes coming up motor has 3 summers on it less than 20 thousand kls anyone have this happen it is a 1994 bravo stock bore 454 boat motor with 1999 279 casting heads tbi edelbrock intake manifold lunati efi camshaft installed staight up the mild one stock 1991 ecm 1999 gm dual exhaust with two cats i believe the timing is 5 degrees btdc
i hope not the y pipe with cats was 700 plus and they have less than 10 thousand kls on them
1. Proper punctuation and sentence structure would be appreciated. That would be taught in our schools starting about third grade.
2. "Stink" in relation to exhaust gas is almost always a result of excess hydrocarbons. The other components of exhaust gas--water vapor, CO and CO2 are colorless and odorless. NOx has some color, and some odor, but isn't much of a problem at idle.
3. Excess hydrocarbon in exhaust is usually the result of MISFIRE, including misfire from too-lean fuel mixture. ANY cause of misfire will throw lots of hydrocarbon in the exhaust (except a
non-firing fuel injector.)
4. Excess misfire can kill a catalyst in a few days.
5. I would connect a scan tool to read the data stream looking for clues.
6. A cylinder-balance test is good for finding weak or dead cylinders (misfiring cylinders)
Good luck!