Intake clean. WOW!

clayp · February 5, 2018

I've been running a tank of E85 once every 5 fillups or so to try to dissolve any deposits. Has anyone who has used E85 often had an issue with these deposits?

Nanotech Environmental · February 5, 2018

17 hours ago, clayp said:

I've been running a tank of E85 once every 5 fillups or so to try to dissolve any deposits. Has anyone who has used E85 often had an issue with these deposits?

Actually, doing that won't have any effect on this issue. Basically the issue is deposits on the stem and back of the intake valves. This is caused by the fact that the intake vales run a bit hotter now, as they don't have fuel vapors and mist cooling & cleaning them off like on old school carbed, TBI and port injected engines, and there is oil vapors coming in the intake from the PCV. When these oil vapors hit the intake valves, they coke and form deposits. Deposits can also form around the intake port beside the valve seat as well. The deposits gradually build up until it starts causing issues with power, fuel mileage & driveability.

Since none of your fuel is getting to the stem of the intake valve, it doesn't make any difference which fuel you run.........

Edited February 6, 2018 by Nanotech Environmental

clayp · February 6, 2018

18 hours ago, Nanotech Environmental said:

Actually, doing that won't have any effect on this issue. Basically the issue is deposits on the stem and back of the intake valves. This is caused by the fact that the intake vales run a bit hotter now, as they don't have fuel vapors and mist cooling & cleaning them off like on old school carbed, TBI and port injected engines, and there is oil vapors coming in the intake from the PCV. When these oil vapors hit the intake valves, they coke and form deposits. Deposits can also form around the intake port beside the valve seat as well. The deposits gradually build up until it starts causing issues with power, fuel mileage & driveability.

Since none of your fuel is getting to the stem of the intake valve, it doesn't make any difference which fuel you run.........

great explanation thanks

ByronSing95 · April 3, 2023

Hello guys , anyone still here to help. I have a 2016 gmc sierra with 5.3 in it, i have changed injectors, maf sensor, O2 sensors , spark plugs , but still P219B keeps coming back. Wondering if a good cleaning of the chamber and intake would be my issue. Any thoughts ? Truck has 125,000 on it