teamstream

Well, i was watching the OLD video the other day on optisparks that someone posted. My 95 trans am just had the motor rebuilt and my buddy took 2 optis, and made one. (one had a crack in it). After I did the motor swap it seemed to run good. I however havent drove it but one time and that was around the block before it got cold out. it seemed to run pretty good then. Lately it seems to have a miss to it. No codes are bein thrown either. Anyway after watchin this video i noticed if you take the vacuum line off the opti to the air cleaner its suppose to have suck from the line and mine dosent. and from the other vacuum line that runs from the opti to the intake it has vacuum from the intake side. so....does that mean my opti isnt sealed properly and maybe it just needs a new one?

Injuneer

Confusing... you indicate you only drove it once, but it appears you are now driving it more regularly, and it is misfiring.

You indicate there are no codes? Are you basing that on actually scanning it, or relying on the fact the SES light did not come on?

You need to verify you have vacuum present at the Opti. Pull the line off the cap, and verify that you have vacuum, all the way back to the connection on the intake manifold. If you have vacuum (remember there is a flow limiter in the vacuum line, so you might not feel the vacuum unless you hold your finger completely over the end of the hose) at the Opti end of the hose, that vacuum line is good. If you don't have vacuum, you may have the hose installed backwards, and the check valve is preventing vacuum from reaching the Opti.

Reconnect the vacuum line to the Opti cap. Feel for vacuum on the air syupply connection on the body of the Opti. Then reconnect the air supply line to the Opti, and verify you have vacuum at the nipple that pushes into the intake elbow.

Shoebox has info:

http://shbox.com/1/opti_vacuum_hose.jpg

http://shbox.com/1/opti_vacuum_harness.jpg

http://shbox.com/1/opti_vacuum_conn.jpg

teamstream

well i have a somewhat fancy code reader, and everything is clear. the vaccuum line coming from the intake, i disconnected it past the second check valve, and it had suction there...on the intake side. im just not gettin any suction on the line coming from the other end that plugs into the air cleaner fitting. The lines are connected correctly ..since i marked the hoses when i took everything apart. when the car is running, and I rev it up it, it will pop out the exhaust at times, and after i rev it and let off it acts like it wants to die? like i said my friend had the opti apart and i think maybe he didnt get the cap tight enough maybe? im not sure. I should of just installed a new one while the motor was out.