I am sure oil will have nothing to do with a engine code. Car is a 99 nissan motor is a 2.4 and code is po400 (stored code comes on almost daily). Its for the egr and egr valve is clean and good and maybe 2 yrs old. I have used carb cleaner in therein the port to clean and seems to help with the light staying off for awhile. This weekend i got some flexible wire and used it also. So question could the Valvoline Restore and Protect help or would it not? I dont think will help with this but wanted to ask
Oil and engine code
- Thread starter moparguy
- Start date
dnewton3
Staff member
Highly unlikely that R&P is doing to fix a problem which, in your own words, indicates that the EGR is already "clean and good". Especially given that the EGR system is not bathed in oil in the first place ...
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p0400 means not enough egr flow. This doesn't mean it's the egr valve at fault. Any obstruction anywhere can cause it.. the egr flow is calculated by subtracting what it should be from the air flow that's measured.
There is more to just cleaning the EGR. Being a '99 there is possibly a solenoid and/or vacuum and temperature monitor to control the EGR. The engine computer monitors and controls the EGR.
