put on my headers, new coil, Crane gold 1.6 rr, and new hardened pushrods along with plugs, got done today. started it up and its missing bad and im getting the flashing ses light. checked the wires, none are crossed, everything appears in order, save for the misfires. Is it possible that the lifters need a few minutes to prime and this will go away, or should i readjust everything again?? anyone ever ran into this problem??

 

You are sure you have the wires on right ? Also, maybe you set the preload on the valves too tight.

 

no, the wires are not crossed. ill need to double check that they are all secure on the plugs, but im almost certain that they are. As far as the preload, im sure i didnt set it too tight. in fact, now that i think back on it i only did a little over a half of a turn. maybe 3/4 of a turn. cant think too well right now, only about 2.5 hours of sleep in the last two days. but in any case, can their mis-adjustments cause misfires??

 

Anything that alters the speed of the crank can cause a detected misfire. The crank position sensor monitors this. I would bet it is ignition related though.

 

ill triple check everything tommorow after i can move my fingers again. headers are a bitch.

 

Sometimes when you can step away and come back later, you see something you did not see before.

 

very true

 

Sounds like the rockers are too tight. How did you check for zero lash. (What method?)


Is the the car having trouble keeping an idle? Often when they are too tight, the car will won't idle , and throttle response will be bad, and sometimes you have to step on the accelerator pedal to start the car. And you might get an SES light which is sometimes the O2 sesors because the car is running too rich. (Not much compression because the valves are not closing all the way, when they are set too tight. )


Again , what method did you use to check for zero lash?

 

Sounds valve train related... Trust me... I'm getting ready to install a new spring and valve today. Pics of carnage coming soon...lol

-Shannon

 

i checked for zero lash by tightening down the nut by hand, feeling the pushrod untill i would not move up or down, then would not twist. right now the car will idle, but very rough, and the ses light blinks.

 

unless you have them VERY tight i dont see how they could cause a misfire. are you sure the plugs are on the opti tight? and how certain are you the opti is on correctly.. i have seen a vented opti put on wrong before but the timing was so far off it wouldnt fire but theres also more than one way to index it wrong.

using the method where you rotate the crank 180* at a time to get all the rockers set worked fine for me. and i found zero lash like you did and proceeded with another 1/2 turn to sink the pushrod down in the lifter so theres no gap.

 

Yes the valves can aause a miss fire it happenned to me. I finally adjusted them while the car was at idle... I believe shoebox's site tells how to do this if not i will post it, it is very easy. JMHO Matt

 

I think they may be too tight. The reason I asked what method you use to set them is because when you check for 0 lash by using the method of turning the nut until the pushrod get's so tight it wont twist. That is very tight already.

That seems too tight in the first place, let alone the extra 3/4 or how ever many turns you would like to go after 0 lash. Maybe just checking for 0 lash by turning the nut until there is no up or down movement with the pushrod is better, ...... then going the extra 1/4 , 1/2, 3/4, or 1 turn.

If you turn the nut until the pushrod can't even twist..... thats very tight already.

 

The difference between "no up and down" and "can't turn the pushrod" is only about 1/16 of a turn, so the lash is probably ok.

 

i checked all the plugs and wires, all are fine. I believe im going to check and make sure that the pushrods are not too tight. ill probably have to pull a bunch of crap, including all of the plugs so i can freely turn the motor. but i think im going to find TDC, and set up all of the rockers on one turn and all of the others on the next, not each one individually like i did. hopefully i can get a snap on computer tommorow morning and pull the codes on which cylinders are misfiring. AHHHHH! so annoying.