403 Olds CCC Swap Gone Wrong

[jetsetw31]

Also, hooked up the vacuum gauge again and it was 15 dropping to 12 after proper warm up and idling.

Start checking for vacuum leaks.

 

[jpoole]

Also, hooked up the vacuum gauge again and it was 15 dropping to 12 after proper warm up and idling.

Start checking for vacuum leaks.

I don't think I wrote that correctly.

after warmed up and idling it was pulling 15 inches. then the engine would lope and then it would drop to 12 then back to 15 etc.

 

[jpoole]

Hi Guys, one more question before I remove CCC. When the computer goes to closed loop, what exactly happens. The car is running along fine no backfires idle good. dwell showing 30 and plenty of vacuum.

When it seem to go to closed loop, and the dwell starts swinging, it goes up to 38 and seems to almost die, then it swings again to 25 and seems to run fine, except the dwell keeps dropping all the way to 6 and the rpms go up and the idle smooths out. This is when the back firing starts.

Also no back firing when the CCC system has a connector removed, such as the MC solenoid or distributor connector.

Today I backed the mixture screws out by a half turn 2 times resetting the computer each time. Same thing, down to 6 and starts backfiring.

Also, after the swap my AC quit working. A dyno was performed after the swap and the CCC was in limp mode with Check Engine Light on, Air Fuel was good. At this point there are no CELS.

Thanks, Jeff

 

[jpoole]

These CCC systems are very touchy and can be mysterious sometimes.
One thing I just encountered with my '85 442 a few weeks ago was a bad prom and it had rough starts and wanted to die all the time.
It was messing with the RVB and EGR by cycling them on and off all the time.
The car sounded like it was excessively knocking during startup like I had thrown a rod, it was that bad...
It was not throwing any codes either which had me very confused as to what the problem was.
I had to disconnect the EGR solenoid block which also controls the RVB and had to bypass the solenoid by hooking up the RVB to the back of the carb and EGR to the ported vacuum just like earlier setups to fix the issue temporarily.
I just installed a used Hypertech chip and it solved the issues and runs better than ever especially with the additional advance it gives at WOT.
I have an NOS one of those lying around too, always good to have spare parts with these CCC systems.
I've been buying GM/Delco sensors whenever I can over the past 2 years, much of this stuff is better than the aftermarket stuff, especially the O2 sensors.
I have heard people having issues with Bocsh O2 sensors causing rough idle as well.
Use GM when you can...

Can the proms go bad? What about the computers? I get no codes and it was working fine before the swap but who knows.

thanks ,jeff

 

[88hurstolds]

Absolutely, my 85 had a similar problem and was fine after swapping out the prom.
I have an '83 ECM lying around, It's not a BPA but was a GM replacement for 83 VIN 9s that came out of an 83 Hurst if you think the unit is bad all together. I think it has an ANK prom in it.

You really should talk to Luke, 83hurstguy, about this subject.
He's already been through all this with his 307 and knows the computers limits.
I have a suspicion that he will tell you that you have too much cam as I mentioned earlier.

 

[DoubleV]

My take is if the engine runs good during open loop ( where it's running rich ) and then runs crappy once it goes into closed loop ( where it's trying to run lean ) would mean the engine just wants more fuel. Either the carb could be out of tune or the guys who modded your carb didn't do what was needed (or did it wrong ). I think calling the carb guys and telling them of your issue wouldn't hurt.

Bad PROM/ECM could be the issue too but if it was perfectly fine before the swap then it seems unlikely it suddenly went bad after the 403 swap.

 

[jpoole]

I appreciate all the help with this but I have had this motor in for 4 months and only been able to drive it 150 miles. I am tired of chasing the gremlins that are the CCC system.

I have a Holley 4160, DUI HEI and Monster Trans lockup kit and will be installing next week. Problems are how to hook up the lockup kit cleanly, getting the AC to work (want to keep my throttle cutoff) and electric choke from the ECM area.

I have read posts by DoubleV on these items but don't fully understand how to accomplish.

I just want to be able to drive my car, no fun sitting in the garage!

Phase III will be Multi-Port FI, so CCC was just a temporary situation anyway. Have a manifold but will be adding parts over the next year of so as I am able to afford.

 

[jetsetw31]

I appreciate all the help with this but I have had this motor in for 4 months and only been able to drive it 150 miles. I am tired of chasing the gremlins that are the CCC system.

I have a Holley 4160, DUI HEI and Monster Trans lockup kit and will be installing next week. Problems are how to hook up the lockup kit cleanly, getting the AC to work (want to keep my throttle cutoff) and electric choke from the ECM area.

I have read posts by DoubleV on these items but don't fully understand how to accomplish.

I just want to be able to drive my car, no fun sitting in the garage!

Phase III will be Multi-Port FI, so CCC was just a temporary situation anyway. Have a manifold but will be adding parts over the next year of so as I am able to afford.

I understand your woes concerning the CCC. Everyone that gave advice had a good point and that proves just how multiple the issues of the CCC can be. Even though I got mine running on it, I was always prepared to ditch it because it's temporary and holds back my motor from what it's truly capable of. The biggest problem with the CCC is it's limited ability to sense what the engine is doing. And we all should agree that for true HP use, the CCC can't hold up.
To put it more exact. If you want to operate your car within the 1000 -4800 rpm range (Normal driving) your factory CCC can handle it. If your engine is capable of going past 4800 and you push your car sometimes, then your out of the CCC's parameters. (The H/O and the 442's CCC are exceptions)
My plans are similar to yours, FI with aftermarket control system as cash flow allows.

IMO, you have a unique problem, so If those gremlins are still scoring touch downs on you, then stop going crazy chasing them and go non CCC.
T

 

[Clone TIE Pilot]

You have to remember that the CCC will only work correctly if the engine itself is working correctly. I have seen many times people blaming the CCC being a bad system and replacing it would be the fix, only to have the problems still persist after the removeal of the CCC. My motor with a aftermarket cam didn't want to idle, turned out it was a vacuum leak. Fixed the leak, adjusted the IAB valve and went from stalling to a super smooth and strong idle, my carb was also SMI rebuilt. Stock L69 305s run 9.5:1 CR from the factory and the CCC runs fine with them. Also you should not adjust the idle mixture with the lower idle screws, rookie mistake, you should adjust the idle mixture with the IAB valve instead. Just a slight turn makes a world of difference.

If the CCC is checking out ok, then you need to check the other systems out, check for improper cam timing and dist timing, vacuum leaks, cold T-stat, etc. It really sounds like a lean problem and you should find out what is causing it since a aftermarket carb won't solve vacuum leaks or off timing. Here is a link to a dealership CCC repair checklist that will allow yopu to find the problem and fix it, you will need to scroll down. http://www.earlythirdgen.com/forums/viewtopic.php?f=29&t=769

The backfiring sounds like the smog pump diverter valve isn't working right. When you release the throttle, the air from the smog pump should be diverted from the exhaust and into the air cleaner to avoid backfiring.

 

[jetsetw31]

You have to remember that the CCC will only work correctly if the engine itself is working correctly. I have seen many times people blaming the CCC being a bad system and replacing it would be the fix, only to have the problems still persist after the removeal of the CCC. My motor with a aftermarket cam didn't want to idle, turned out it was a vacuum leak. Fixed the leak, adjusted the IAB valve and went from stalling to a super smooth and strong idle, my carb was also SMI rebuilt. Stock L69 305s run 9.5:1 CR from the factory and the CCC runs fine with them. Also you should not adjust the idle mixture with the lower idle screws, rookie mistake, you should adjust the idle mixture with the IAB valve instead. Just a slight turn makes a world of difference.

If the CCC is checking out ok, then you need to check the other systems out, check for improper cam timing and dist timing, vacuum leaks, cold T-stat, etc. It really sounds like a lean problem and you should find out what is causing it since a aftermarket carb won't solve vacuum leaks or off timing. Here is a link to a dealership CCC repair checklist that will allow yopu to find the problem and fix it, you will need to scroll down. http://www.earlythirdgen.com/forums/viewtopic.php?f=29&t=769

The backfiring sounds like the smog pump diverter valve isn't working right. When you release the throttle, the air from the smog pump should be diverted from the exhaust and into the air cleaner to avoid backfiring.

X2 with an exclamation point!!
T