Coleroad

Azz said it happens when he accelerates hard. It is going to be rich at that moment. Causing the chemical reaction in the catalytic converter. BGW when you removed you 3rd one. It reduced the catalytic reaction. This would help stop the sulfur smell.

Bgw70

Cole, would anything in post 6 make matters worse, if they are old parts? Azz has 97k miles.
Would the wrong plugs cause this...

Yes, mine was really bad until the third car was removed...never smell it now. It was only with the top down and WOT.

In post 12, azz said it began to smell after the work was completed...

What do you think is the problem?

Coleroad

I doubt it had anything to do with the work he had done. If I was making educated stap at parts that could contribute to this. MAF sensor ( I m not a fan of cleaning. I think replacement is the only way to go. Only exception to this for me is if you have an oiled air filter.) pre cat O2's, or professional fuel injector clean.

Bgw70

Do you think any of the items should be replaced that are listed in post six?

Do many folks here run a K&N air filter?
I do...

So azz, change the mass airflow sensor, number one O2 sensors on bank one and two, then have the fuel injectors cleaned professionally.
Cole, would that be performed by removing each injector or running the cleaner through all injectors with the engine running?

Coleroad

I would get the injector cleaning first. Then pre cat. o2's. The maf I wouldn't change without testing it.

theazz

Well I installed the spark plugs and know they are correct. I guess my next step based on all your comments is try injector cleaning. What do I look for to get this done or is this something I can do.
Thanks for all your comments

Coleroad

You want it done somewhere that disconnects the fuel pump. Runs the engine on pressurized cleaner. The only other method that works well is to remove the injectors and clean them. This is the best way but expensive. When they are out you can flow test them. Cleaner you add to the tank is more of a preventive thing.

Bgw70

Do you think it started all at once after you changed your plugs or was it gradual?

Have you changed or cleaned all of the items in post 6, minus spark plugs?

Coleroad

Here is the reason for my suggestions and why the order. He has almost 100K, the injectors have varnish on them. I don't care what kind of gas you used, there is a build up. The fuel isn't atomized like it used to be. Let's say 1% more of the fuel doesn't get burned now because of it. That is then a rich exhaust getting to the cats. I suggested first because it will help the injector spray pattern. It will have a slight cleaning of the cats. It can be harsh on the O2. Which is why I would suggest that if needed it be done after the injector cleaning. If cleaning fixes the problem your done. If not, like I had stated I see the pre cat O2 as a maintenance item. You will see an increase in gas mileage if nothing else. Still have the problem? If the maf is not giving an accurate reading it can cause big swings from lean to rich. The maf can read within normal range as far as the computer knows, but be off enough to cause issues. Just not bad enough to cause a code yet. Now the air filter would have to be very dirty to be causing this condition. On computer controlled engines. A dirty filter just creates a lose of power, because the computer will keep the fuel ratio within a tight range. in a carbureted car the filter makes a big difference in the air fuel ratio.

theazz

Honestly can't remember before or after the pugs but noticed it early summer when I had the top down. Car doesn't miss or lose power.
Frustrating.
theazz

Coleroad

Was the car parked for most of last winter?

theazz

Yes car was parked for most of winter.

Coleroad

Yes then that fuel sitting in the injector would tend to varnish. I did two things when I stored my cars for winter when I lived in Michigan. A full fuel tank with sta-bil, and a bottle of fuel system cleaner. Then run the car enough to circulate that treated fuel all the way to the engine. Put the treatments in before fueling. That way the fuel going in mixes it in.

Start with a good injector cleaning. It will be worth it.

theazz

I will do it. I'll get the injectors cleaned with someone who disconnects the fuel line. The injectors makes sense to start with. I'll keep everyone posted.
Thanks everyone

Coleroad

Azz, please understand that nothing stop the sulfur smell 100%. It is a byproduct of the catalytic converter working properly. This is an effort to get it back to a level it was before it became excessive. One more question, BGW had asked if the throttlebody had been cleaned. If not like he said that would be a good idea.