Carbon problems
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Joined: Dec 2013
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From: Leavenworth KS
Carbon problems
Hi folks, Pulled the intake off the C4 last weekend and today I was working to clean things up. There is a ton of carbon in the throttle body, the intake runners and everywhere in general. Found some vacuum ports plugged and the EGR seems pretty sluggish. I didn't have any code set and the car ran reasonably well. Any thoughts on where to look. Thanks
Le Mans Master
Joined: Sep 2006
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Carbon
You don’t have a problem.
its the EGR soot.
you flood the intake manifold with exhaust to partially fill the cylinders with already burned Exhaust so that your car puts out less emissions, but The byproduct is soot.
just clean it up and press on.
as for the egr valve, you can clean the valve part, and operate it with a Hand held vacuum pump.
it has a bleed off hole in the body, so it won’t hold vacuum, but u can operate it
its the EGR soot.
you flood the intake manifold with exhaust to partially fill the cylinders with already burned Exhaust so that your car puts out less emissions, but The byproduct is soot.
just clean it up and press on.
as for the egr valve, you can clean the valve part, and operate it with a Hand held vacuum pump.
it has a bleed off hole in the body, so it won’t hold vacuum, but u can operate it
Last edited by coupeguy2001; Jul 19, 2020 at 04:44 AM.
Thread Starter
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Joined: Dec 2013
Posts: 64
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From: Leavenworth KS
I check it and it is operating so I will clean it up and reinstall. I was amazed at the amount of soot. My previous experience with Ford 302 was this area stayed pretty clean. It was filthy but I guess it does have 110,000 miles on. Hopefully this will perk it up a bit but wasn't running bad when I took it apart!
Le Mans Master
Joined: Sep 2013
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From: near the thumb in the mitten
The throttle bodies will carbon over time and periodically will need sprayed with cleaner. The hot pcv vapor will cling to the cooler aluminum. It may have been a while since it's been apart.
