This may be a noob question, but i couldnt find an answer online so I'll ask you guys.

If your truck is runing rich, would any adjustment to timing help? Want to play with my new programmer, saw that I could adjust the timing, and I have been told by a few shops that it is running rich.

Been battling a slight rough idle since i got the truck and if I am parked in a garage having work done and the truck is cranked, the whole shop will smell like gas/exhaust within minutes.

 

Hi.

No. And don't play with that without a corresponding octane change.

How old are yer front O2's?

This is overly-simplified but -

In closed loop ( idle, part throttle cruise, light load ) AFR is controlled primarily by feedback form the front O2's.

In open loop, ( WOT, high loads, > 70-80% throttle ) enrichment and yer AFR is controlled primarily by the MAF transfer function and the MAF table in yer PCM.

Unmetered air ( air/vac leaks ) will cause the PCM to enrich to maintain stoich AFR. Same with exhaust leaks before the front O2's.

Leaking injectors are another potential cause. As are misfires. Both send raw unburnt fuel downstream.

Need a competent shop with the requisite instrumentation & expertise to nail this one properly without just throwing parts at it.

Start by pulling any stored / pending codes with an advanced diagnostic scanner.

Maintenance - cleaned the MAF lately? Plugs? Those O2's? Etc, etc...

MGD

 

I, personally, wouldn't mess with timing parameters.....a move of 3-4° either way COULD potentially be catastrophic.

 

Yes, I have done new MAF, Plugs and O2 front and rear. Also new cats and new manifolds.

Still has the shake at idle and still smells like running rich. I thought the injectors were suspect. Will have a shop check it out.