OK now on to Plan D 1986 Bonneville GS

[Jim_Rockford]

Ok folks, back again with a New project,, Operation "CCC system Restoration"
I have purchased a fine survivor of a 305 ccc 4 brl 2004r G body , stashed away in a crappy 1 car garage since the sad year of 2004 , due to a non operational transmission . got it home and running in a hour or so with just filling the carb bowl through the vent and she roared to life . Sadly didnt pull in any gear. 20210102_153659.jpg so I rebuilt the Trans, new convertor I had to replace the 4th gear pressure switch cause it was showing closed and if you applied any air at all to it it leaked around the crimp on the outside. removed the carb, cleaned it out and made sue all the air tubes where rodded out with a torch tip cleaner set. can runs flawless, CCC seems to be commanding timing because it changes to the default base setting when you unplug the 4 way to set it. Found some good videos from GM about recalibrating the carbs when they come in for a 25,000 service and explained how finely calibrated everything is including the seals for the accel pump and TPS plunger to keep out ambient air, and this is really a good system in theory and some of the cars when new had milage in the mid 20s on the highway if maintained properly. Im thinking alot of these systems got a bad rap due to lack of knowledge as to how sensitive these carbs are compared with Prior non electronic q jets. But i have regeared the rear with 3.42 gears compared to the Namesake 2.41 that is came stock with. added some New 225/70/14s on some pontiac 14x7 rallys , changed the governor gear so the speedo it within 1mph of the gps reading.20210404_185651.jpg

Plans are to make this system work as advertised. I have a monte SS chip from a 1987 , now currently I have the stock 7169 ECM with a FFU prom. Check engine light comes on and then goes right off once you start the car and you never see it again till the next cycle. I tried swapping the SS chip in and the check engine light stays on , didnt pull the code just figured it was the mix match in years, but turned out I have head the 87s had a different ecm that was a little faster so Im wondering if I do swap to the 87 305 ECM will it work with my current 305 system?

[dave w]

Are the definition files the same . . . 86 Bonneville GS vs. 1987 Monte Carlo SS?

https://www.tunerpro.net/downloadBinDefs.htm#GM

I was not able to find ECM 1227169 in the link posted above.

RockAuto showed the 1227169 ECM as 1986 only.

dave w

[Jim_Rockford]

yeah I think 86 and 87 are one year only PCMs figured they were different before looking them up seeing as how My current 86 prom is only a 3 letter code VS 4 digits for the 87 and newer
I read a few thread over on Third gen.org and several folks did the swap and said their stuff ran better, another thing that I need to check on, is I dont think Im feeling the converter lock, I tested the lock up solenoid before I reinstalled it it worked fine, so I suspect this ECM might have a problem. I havent tried to pull codes on it mainly cause I have been busy getting it road worthy. new front brake hoses, New pad, swapped out the airplane gears for normal street car gears, stuff like that, im currently installed a set of factory rally gauges and will have the Tach hooked up tomorrow and I can see if the RPMs are dropping.

[stew86MCSS396]

I think this is the one you want... http://www.montecarloss.com/communit...Number=1027530

[Jim_Rockford]

good thread, I went over today so I could bring the car home from the shop to my house...(Hard to drive 2 vehicles at the same time. ) and grabbed two proms I had and I was correct The one chip is for the 87 L69 ss the other was a old chi from a 90 9C1 police car I owned withe TBI LO5 so thats one isnt going to do me any good..LOL

[Jim_Rockford]

Took the first road trip in it and the result was 21 mpg so Its close and thats with a 3.42 gear stockers where 2.41s.