So yeah...

I just finished the install of my XE 236/242 .555/.576 112LS on stock heads. I'm using Crane Gold rockers, Comp R lifters, Comp hardened pushrods, and Crane 99893 dual valve springs. Converted to a Cloyes double roller timing chain, CSI electric water pump, Holley 52mm throttle body, and added Jet Hot long tubes while I was at it. Here's the problem, and I'm sure it speaks for itself. It's kind of embarassing really, but oh well, what can you do?

Cam Idle.

The car will NOT idle or start by itself without motivation of my right foot, nor will it start without opening the throttle blades manually. You'll see it in the video, and my reaction when it doesn't. LOL! It's also backfiring like you wouldn't believe, as the video shows. (it's actually quite funny watching my friends get frightened...listen to the one guy start laughing ).

I'm running open Jet-Hot long tubes at the moment, and relatively old O2s along with a new PCMforless program. What the HELL could be the problem? Valve lash?

I also had to slot the TPS sensor to get the original voltage from the stock throttle body. Stock was .61v, and with the Holley it jumped to .75v. I slotted and readjusted it down to .61v, but no change.

On another note, I had the intake manifold powdercoated House of Kolor metallic green. It looks pretty badass, and if you remember my "GTO badge" post, you'll see what I did with the other badge!

http://www.ramair95ta.com/car/engine.JPG

Any takers? I appreciate any help you guys can give me.

EDIT: If it's any help, the dowel pin was cut to about .610 long, +-.005".

 

Vacuum leak...my guess is brake booster line.

What do I win?

Edit: Okay it appears to be connected but my money is still on vacuum leak.

 

had the same problm the other day on the install of a new motor with 230 236. the iac motor went bad and flooded the cylinders with fuel and the exact same thing was happening just as you descibed. pull a plug out and see if it has a large amount of fuel on it.

we replaced iac motor and clean all the plug and the car fired up first shoot.

 

re check plug wires, if its not them, then re-ajust the rockers and put less pre load on them try a 1/4 turn instead of what you did( i only wsed a 1/8 th a turn after zero lash )

If none of the above just go back and recheck everything

 

hey noticed the name of the video. is that a joe O. cam

 

two things, one, after you run it initially, always go back and relash the valves while the eng. is still hot. two, it will pop w/open headers. that doesnt explain the idle problem though. seems to do alright at light throttle when your holding it though. maybe all that air is getting back into the headers and being pulled into the eng. that way? I would relash the valves, and install the ypipe before messing w/it too much. are you waiting for a ypipe like me? mine should be here anyday. maybe. if they ever feel like shipping it. one day.

 

no HIS name is Joe

 

I had horrible cam problems when mine first went in. Bad starting problems, skipping, loss in power, nasty surging, car shaking in 6th and all kinds off stuff. Come to find out I had 2 cylinders on 0 compression from bad valve adjustments.

 

valve lash, and plug wires. i would check those first.

 

Mine sounded like that and I had swapped two plug wires on one side of the opti. re-check them!

 

First thing that came to mind for me is plug wires. Next would be valves.

There's no way you would get that much popping for a bad IAC motor or the fact that it has open headers. NO WAY IN HELL.....

And if that was my friend in the background laughing at me, I would have kicked his a$$, no second thought about it.....

 

1/8 of a turn on the Comp rollers, no more!! I tried a little over 1/4 turn with mine, and the car would barely idle. Now I am just over 0 lash, try to shoot for 1/8th and try it again.

Although the backfire is kinda wierd, bad lash wouldn't do that I don't think. That sort of thing is caused by an ignition problem most times. Like the others stated check and triple check your spark plug routing, and numbering.





Reid

 

Im having the same damn problems with the exact same setup except that I have a Holley 58mm TB and the 236/242 is on a 110lsa.

It was running fine till I drenched the Opti...now it won't even idle, if I try to give it gas to keep it running.... it sputters and back fires, but will be fine after 3.5Krpms. I adjusted my rockers the first time around with 1/4 past zero lash...and still no luck..did it 4 more times...still no damn luck. So I tried 1/2 lash and no luck either. Im gonna try 1/8 past zero lash and if that doesnt work.....then swap my old opti in and see if that will help.

-B

 

You have to big time TUNE for the Holley 58mm TB, its got no BYPASS for idle air, almost all air goes through the IAC, you have to adjust the IAC follower table a lot or the car just plain & simple WILL NOT RUN WITH HOLLEY TB, don't get me wrong, they are awesome TB's, there is a reason they did this & thats to prevent reversion from big cam, but to make them run you need to tune big time on the IAC follower tables I repeat!

 

He's using the 52mm, not the 58mm.

I wish I could help Joe, but without being there looking at the car, it could be a hundred different things. Did you make sure everything was plugged in, like sensors, etc.?