Just finished a heads and cam swap, the heads are ported Dart Pro 1 200s, the cam is a CC306, car has SVO 30# injectors, fuel pressure regulator is stock, the PCM4less tune is set for stock fuel pressure. The issue I'm having is the car will not idle, it's just rich as hell, enough to light up inside the intake manifold. If you give it gas and rev the motor, it revs up fine and is responsive, the car just wont hold an idle on it's own. I converted to a vented opti when I did the swap. It'll crank up on the first try every time, just usually die right away unless you hold the throttle open. From what I have read, the issues could be related to a really bad vacuum leak, or an issue with the tune. I'm thinking about swapping the bolt on tune in the car and seeing what happens.

 

Try setting the idle around 1000-1200 for 10-15 mins. Is there an established CC306 cam "break in" procedure?

 

What TB are you running?

 

AS&M 54mm, was on the car before hand with no issues. I just really don't want to jump the gun and start blaming things.

 

Did you check all vacuum lines, opti hook-ups?

 

Going back through that right now, I'm thinking I may have had the FPR plugged in where the HVAC vacuum connection went, not sure, in the right place now. The Evap purge is on right, on the opti the diameter of the fittings corresponding to the diameter of the hoses on the vacuum harness since they are different from one another, I'll check that again though. The egr has been removed, the vented opti now uses that port since the cars a 93. The solenoid(?) for the EGR on the side of the intake manifold has the plug hooked in, no vacumn lines since the EGR is gone but the ports are open. I'm thinking I should cap them any way, EGR should be tuned out.

 

If there is no vacuum line from the nipple on the manifold to the EGR solenoid, it doesn't matter whether you cap off the connections on the EGR solenoid. Did you put blanking plates on the back of the manifold for the EGR connections and seal them tight?

When you say its running rich enough to "light up inside the intake manifold", do you mean its backfiring through the intake? That would indicate a problem with the valves, or the ignition timing.

 

The EGR is blocked off with SJM plates, I have double checked all the vacuum connections, I used my buddies 94 Z28 as reference on the intake manifold so every thing should have been hooked up right. The opti was brand new new, took our time putting it on, I believe I have read there are three possible ways to install it, with the two wrong ways you wont get spark, we have spark. It did back fire through the intake, my TB looked like it was smoking a cigar. The issue may be with the valves, I guess if their two tight we aren't getting enough air in the cylinders to get proper combustion. Thanks Fred, once I get the Coolant x-over fixed, that'll be the next thing to try and mess with.

 

We took out an 1/8 of a turn on the rocker nut thinking they were on to tight, the car fired up, tried to idle for maybe a few seconds then cut out. Tried to take another turn out the rockers, this time the car would not start and just back fired through the intake. Found a leak at the coolant cross over tube and fixed that, so I guess some progress was made as well as fixing all the exhaust leaks we had. I swapped my bolt on chip back in to see what would happen, did the same thing so it's safe to rule out a possible tune issue with the car.

 

I would almost take a stab and say you've got your rockers tightened down too much then. I had that problem when I first got my car back together earlier this spring.. Loosen them all up a bit and try it again. Then you can adjust for valve lash anyways..

Hope that might help a bit..

 

On the 95-97 vented Opti, there are three possible locations to insert the dowel pin into the back of the Opti. You will get spark no matter which hole you put it in. But with the incorrect locations, the timing will be 120 cam degrees.... or 240 crank degrees advanced or retarded. You can see where this will cause backfiring through the intake.

With your 93 and the unvented Opti, the splined shaft can be inserted in 16 different positions, allowing the timing to be anywhere from dead on to huge errors.

Courtesy of Shoebox:

http://shbox.com/1/93-94_opti.jpg

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

 

Given timing and tuning is good enough for it to idle, crack open the TB blades slightly to see if it holds. (using idle stop screw). I had to enlarge the idle hole on my stock TB on my 93 w/ Ported & XE 230/236 cammed engine for it too hold a decent idle.

Also make sure your MAP readings are decent, you should see at least 10-12 inches of vaccumm.

As for tuning, my VE table has values of 48-50 in the 600-1000 rpm range. I also have 30# SVO on stock fuel pressure setting. I verified on dyno, AFR was good. Idle Timing is set around 28-30 degrees.

You may consider running a open-loop tune only, I had all sort of problems with 02 sensor readings in the 93 that I did not experience on the 96Z. If you have problems it will throw fuel curves off everywhere.

Good Luck.

 

The car has been converted to a vented opti, we got it to idle on its yesterday for a few minutes, had a crossed plug wire so it stopped back firing through the intake. The car was really rich, as we began to adjust the valves it sounded like it wasn't firing on all 8 to the point where we could not get the car to start any more. The car was running really rich so I plan to check the plugs and see of they possibly fouled out. Some thing that seems worry some is, the fans would come on soon as we keyed forward, checked all my fuses, they were good. So I hooked the code scanner up to it, would not make communication with the ECM to flash the code via the SES light like it normaly does. Later, we hooked up the TTS datmaster to the car and got the error the cable was working but no ECM was was found. Which kind of goes back to the tried and true code scanner not being able to pull any possible codes...

 

If you installed the chip incorrectly or have a bad chip it will do that. Recheck chip installation.

Joe

 

I will check that Joe, thanks for all the help guys. Here is a video to show proof it once had life This all kind of sucks in a way, but good because it's some what trial by fire way to learn.

http://www.youtube.com/watch?v=BwDKBj_WGaY


I realize that the url ends in gay btw