I just traded my old work truck for a 92 camaro rs ,it’s a v6 3.1,it ran rough and had idle stumbles and would stall at lights ,so I replaced everything for a tune up(plugs wires icm rotor cap air filter oil and oil filter,fuel filter and transmission fluid change) as well as replacing the idle air control valve egr valve checked fuel pressure, oil pressure every sensor and went over the computer to make sure all solder points were good on both ecm and prom.so after this I took it to get smogged and failed for gross polluter,so I decided to check the hoses and comb over the wireing and check the timeing cause it was a young kid I traded. Well it was set to 18 instead of 10 .is this the reason I failed and had the gross polluter ,I’m just curious and trying to understand what the results of running an engine that’s that far out of time and if that’s the problem

 

Dont know if thats the only reason, but if the timing is off more than 2 degrees from stock. You will fail the smog test.

 

Ok Yeah it did better with correct timing,was surprised at how far out it was it got close to passing we’re it was a huge fail last smog.it turned out it failed due to my Egr failing.

 

Update :replaced egr and triple checked timeing ,i failed again with gross poluter ,I’m at a loss

 

Air pump still functional? You didn't post what parts of the inspection failed so the converter could be bad.

 

When you set the ignition timing, make sure the distributor disconnect on the firewall. If not, the timing will be off.

 

Took me three tries in California to pass about 6 years ago. The two big things that finally got me (barely) passing we’re the AIR Pump and EGR Valve — I think the valve mostly as it probably was sealed shut or barely operating. If you do those two plus reset your computer and let it adjust after the timing fix, that might help.

 

Forgot to say — I also had a guy running the tests who would show me the breakdown about which particles were failing. Sometimes that helps single out what it is. Maybe you can snap a picture of the report and upload?

 

Coincidentally, if the base timing is set correctly to 10BTC, then 18 degrees is a very typical amount of total advance while idling. At least on a 2.8L Fiero anyway.
So this does raise my suspicions. OP, please make sure you bypassed the ECM advance when you checked the timing.

Your emissions test is supposed to include a timing check, so it should show what the inspector thinks it was.
Do you take the "enhanced" test or the "2 speed idle" test?
You'll probably get better suggestions if you post both of your complete test results, along with a description of what was changed in between them.

 

Ok so I’ll upload pics of report so I decided to comb over system,new 02 sensor I check fuel pressure and it’s right at 43 psi like spec,and decide to check and test injectors,when I pull injectors to test,and right away I noticed whoever owned it last swapped 2 of the 6 oem injectors with two triple flow and left the rest oem,so I’m assuming haveing two high performance higher pressure injectors and the rest oem would throw off everything,I’m just spitballing


Smog results

 

I think you’re on to something — your CO was too high. Carbon monoxide is the result of running really rich, incomplete combustion. The fuel mixture might be off.

 

Yep, all injectors need to be identical for the system to work correctly. Assuming your ECM is stock, I'd recommend replacing all the injectors with a matched set of factory equivalents.

 

I agree that all fuel injectors need to be the same. Reach out to South Bay Fuel injectors (they are a sponsor of Thridgen.org). They have both stock 14 lb/hr and the upgraded 17 lb/hr injectors. I can vouch for the 17 lb/hr units quality, but I'm not sure you will pass smog with them.