I have a question about my intake valves. I was getting ready to do a valve adjustment this evening and noticed something odd. All my intake valves visually looked to sit at an equal height but one of them was off. it appears to be atleast a quarter inch off. I was just wondering if this is normal or not? I have posted a picture below to show you what I mean.

 

there will always be open valves, as the cam rotates with the engine -each cylinder is in a different location/stroke of combustion
One cyl will be firing so all its valves closed,,a few cyls down one is opening so intake will appear lower

this is why you rotate the engine to top dead center for that cyl when adjusting valves

 

I thought so I just assumed the valves on the same cylinder would move together when opening and closing. good to know thanks.

 

the car was running ok before you started the job?

 

no I have a missfire issue and I am checking the valves to make sure they are all still gapped properly. been fighting this missfire for a while now and I am not sure what is causing it. I have read that possible causes may be the EGR port and a possible valve gap issue. I am also wondering if I have a bad fuel inector somewhere as my gas mileage is down to 24mpg's.

 

as long as the intake is removed- clean the egr ports all the way thru the manifold- every 75kmiles is when they need it bad- see diy
that will screw up the running

misfire is often a bad coil
what codes did it read?

dirty injectors and plugged egr will lower mileage
run a can of seafoam in just under half tank of gas- 8 gallons, that will clean anything blocking the fuel system and will clean the intake valve backs and piston tops- all important to running

if a valve was `dropping` low, from bad spring let say, it would make the car run realllly bad,,popping etc
A coil will make a small miss

 

Thanks for the info! I just did the intake cleaning and went ahead and adjusted the valves. Most of them were way off. All the intake valves were .02in. or more off and one of the exhaust valves was almost .06in. off. the majority of the exhaust valves were .02 off though. The car has 188000 miles on it so I am sure it has never been readjusted. Also just drove it for about fifteen miles and no miss and no check engine light. Crossing my fingers it is fixed.