Well I've noticed something that seems interesting as to whether techron in chevron gas really does clean carbon build up. I've had a cel light witha egr malfunction. So this past weekend I took it part of the way off and just tapped it with my wrench to knock any harden carbon build up out. I sprayed some cleaner in and then filled up with amoco gas. I drive all weekend and my light goes off yippie.......Getting low on gas so I fill up at amoco again. Light is still off. So yesterday I go to get gas and this time the best and closest gas station is Chevron. On my way home the light pops back on and I can tell the difference in my car below 3500rpms.
So I talk to a mechanic and he said sure enough that techron does work and it probably loosened up some carbon buildup that was left and clogged my egr again. He said they run it in cars sometimes to clean them out as well, versus throwing in some injector cleaner.
Just thought I would put this out there and see what others thought.

 

EGR deposits have nothing to do with fuel detergents.

The EGR recirculates some exhaust gas back into the intake. It is not related to the fuel system in any way. I'm not saying Techron doesnt work. I'm saying that the only things it can clean are the injectors, the intake ports and the intake valves.

 

Ok makes sense but lets assume it cleans the gunk off the intake valves, and not all of that gets burned where does it go?? out the exhaust valves I presume which would put it in my exhaust track. Sounds like I might be overthinking this..lol

 

It ends up in your cats.

 

EGR system SUCKS...

 

Why do you say that?

 

That's like saying Catalytic converters suck. Even newer cars that have done away with the EGR systems still use variable valve timing to recirculate the gas through slight valve overlap at low revs. Either way you look at it, it's a good thing. It doesn't do anything at WOT, so what does it matter??

 

Not all deposits ends up in the cat. What the original poster is saying is very possible. I've ran fuel injection service on many vehicles and sure enough some (Chevy S10, Blazer, etc. comes to mind) will come back with a customer compaint of idling ruff. Sure enough when I removed the EGR valve you can see a piece of carbon holding the valve open. It became so common at times we just told the customers if the car starts to idle ruff bring it back and we'll check to make sure the EGR valve wasn't being stuck open with a piece of carbon.

 

Because it makes your SES light come on and it's not a lot of fun taking it off and cleaning it. I sure he was'nt talking about it's performance or purpose.

 

Cats do suck. But thats another worthless issue. I just mean its a real SOB to get at under the hood, and i've sunk a little over 250 into replacing my fouled up parts trying to pass emmissions.