Hey hope one of you all has an idea. I installed a hot cam in a friends 96 z28 and now the car won't start. It tries to fire but seems to be out of timing. I also removed the air and egr if that makes a difference. I also checked the sparkplug routing and have new sparkplugs in it. I went back and double checked the opti spark. Any ideas? Does it matter if the rear O2s are unplugged or if the cam was originally for a 94 and we switched the pin

 

Either the pin is to long/short and/or the Opti is not seated correctly.

 

the pin is right and the opti fits on fine. i even took the cover off the opti and looked at the rotor and it seems to be in the right place

 

i just did an opti in my car last night... i thought the pin was in also about 10 times but my car wouldnt start also but when i finally got it right it went right in a fired right up

 

how can you put it on wrong. the pin only fits in one hole on this cars opti

 

how can you put it on wrong. the pin only fits in one hole on this cars opti

 

any more ideas?

 

Not to sound stupid or anything but did you make sure you put the coil wire back on? I was in such a hurry at the end of my install that I forgot

 

i got that on

 

Try reajusting your rockers, they may be too tight.

 

i redid them and it did not change anything. thanks for all the ideas guys

 

Too tight rockers is a very very common error, the books are all sort of ambiguous... symptoms of rockers too tight would be:

The engine will be firing but may not start.

You'll hear the cylinders firing but it will sound like it's blowing out the exhuast/and or back into the intake which might make it seem like the timing is off.

If you get it running it will backfire and pop.


EDIT: dohh.. you snuck that reply in before me. How did you re-adjusted the rockers? What are the steps you are doing.

 

did you check for spark?

 

it has spark. to adjust the rockers i backed them all off and then let them set for awhile. Then i did them in the order the book said, taking them to zero lash and then going an extra half turn. Is that right? Would it matter that i put 1.7 rockers on? Does that change anything?

 

try just going to zero lash and see if it dose anything even a 1/16 of a turn can make a difference. It took a few time to get mine right and i had only one that was off and the car wouldnt idle right.