I got my valves adjusted on Friday and I threw a check engline light on sat. Looked at it and it was codes 71-74 - misfiring on all 4 cylinders! Can having your valves adjusted too tight cause this?

 

No it cannot.

Make sure all the ignition wires are firmly plugged in, and no oil leaks into the spark plug holes. Reset the ECU while you're at it.

 

yes i would definantly take a look at the ignition system and the valvecover seals too. something isn't connected correctly or maybe isn't functioning at all. maybe for some reason something was damaged during the valve adjustment that is causing the misfire. resetting the ECU is always a good idea too.

 

Yes, but they would have to be really tight. What year and model is it?

 

Hes right they can....someone has to be a fool and not pay attention to what they are doing if misfiring occurs on all cylinders....always adjust valves on TDC of Compression stroke

 

if the valves were adjusted incorrectly, like at the wrong timing point, then yes it could really mess up the combustion process including the misfiring.

 

what the **** are you smoking? it sure can cause a missfire if they are too tight

 

the car's a 00 si

 

Is it still codeing? Did you have the valve clearances rechecked?

 

still coding, gonna check it out this weekend. The mechanic adjusted the valves while the car was relatively warm so I dunno if it played a part in the misfiring.

 

tell him TDC on EACH cyl and .007 adj.

 

and make sure the motor is cold when it's done so it's accurate.

 

never suppose to adjust valves when it's warm.

 

true, didn't have much of a choice considering that i had to drive the car over to the shop, and I didn't have much time to wait until my engine was completely cool.

 

They need to be cool. I think the helms says that the temp has to be under 100 F which is still pretty hot. I hope your car isn't jacked since you couldn't wait to adjust them cold.

 

looks like he did that when I observed him, but the order he adjusted the valves was different than what was stated on c-speedracing.com's how-to. Would that make a difference, also how can you tell TDC using aftermarket cam gears such as AEM?

 

Doesnt matter what order it is in...just so the piston is on TDC of compression stroke....you can set the piston at TDC by watching the cam lobes,line up the crankshaft to 0 degrees, or place a screw driver tip down in the spark plug hole and roll it around till you get to TDC.