I recently grabbed a 87 cutlass supreme with a 307 in it. The car sat for a few years prior to reaching me. Since I’ve had it,I’ve swapped out the carb and the fuel pump. It will now idle pretty smoothly, but once attempt to put it in gear it will bog down and shut off if I’m not on the accelerator at the same time. I was pretty diligent on protecting all the vacuum lines when I swapped the carb,so I believe they are solid for the most part. Anyone has any other things i could focus on to try to troubleshoot in getting it road worthy?

Also, it’s really difficult to move the floor shifter from part into other gears. Any specific advice for that as well? Thanks a lot guys

 

You "swapped out" the carb with what? These cars use a computer-controlled Qjet. That same computer also controls distributor advance. If you didn't use another CCC Qjet, the computer goes into limp-home mode and will run like crap. If you DID replace the carb with another CCC Qjet, you then need to follow the adjustment process in the Chassis Service Manual EXACTLY to get it dialed in. Simply bolting on a rebuild will not fix the problem.

 

Lots of possibilities exist. Unless you have a vaccum gauge, a tach-dwell meter and know how to do a tune-up it is pretty hard to start guessing without knowing the basics are in order. Do you have a vaccum leak? Is you timing and dwell correct? Are the plug gaps correct? Is the carburetor correct for your car? etc. My first guess might be checking that the carb is correct since that is what has been changed (assuming the car ran well and did not bog down as you describe before this happened). What kind of carb is it? An older rebuilt one or a new out of the box aftermarket? As mentioned, lots of variables.

 

Joe, you beat me to the "post reply" button.

 

I was going to say that "sluggish" and "307" are synonyms.

 

I replaced the carb with another Qjet. But it is different in the sense that it does not have any plugs on it like the original Qjet had. I didn’t know what those plugs were for. And the car wouldn’t idle at all before I swapped the carb out. Looks like I’ll just need to take it to a mechanic,I don’t think I wanna mess with dialing in a new carb myself. Thanks for the advice!

 

You can keep the non-cc carb but you'll have to swap the distributor for and old school HEI with mechanical advance. If you do that you might as well ditch all the vacuum mess and run only whats required. You won't see any significant power gains but it'll run well once its tuned in.

 

If you want to keep it stock:

NON-CCC carb


CCC carb


You have a problem. You either need to dismantle the CCC system to run that non-CCC carb, or get a computer command control carb for your application. The computer partly controls A/C operation as well, so that stuff needs to be bypassed, and you'll also need a vacuum advance carb instead of the CCC distributor which is now likely locked in to a fixed advance, among other things. Which sucks for you right now.

There's about a million things that could go wrong with your car. You must've got the check engine light already. If not, that's another issue.

As far as the console issue, further describe the issue of hard to get out of park. Is it hard to get back into park as well? I'm not going to play 20 questions with this, but there's a couple few things you could check.

Check the adjustable nylon TOP pin that resides on top of the shifter tube when you remove the T-handle (small U clip under the shifter handle can be removed to take off T-handle). If it's not being pushed down far enough to clear the release pin, you will have a hard time getting it out of park. You can turn it counter-clockwise a bit to extend it slightly to allow the button slide to push it further down the tube when operating.

If that doesn't do much, check the cable- is it original? Adjusted properly? If it is, then it could be stretched. Just figure on replacing it. Since you're going to have to mess with the adjustment anyway to ensure it's properly set, you may as well replace the old, likely original, nearly 40 year old cable. It's relatively cheap. Just ensure you get the right cable for your application, either the 3 or 4 speed version. The old one might be stretched, and sometimes they also act as an alternative ground for a poor transmission ground and can "weld" itself together making it tough to operate. While you're doing all that, check your backdrive linkage to the steering column to ensure it's adjusted properly.

Chassis Service Manuals (CSMs) are worth their weight in gold. Get one if you plan on keeping this car (you can always sell the Toronado manual to recoup some of your money). Think about it, these originally were about $200 from Helm when you could still buy them new. Much cheaper now:
https://www.ebay.com/itm/135183534256

 

Few mechanics knew how to properly tune these CCC cars when they were new. Nearly no one does now. If adjusted following the factory procedure they run great (I've had five of them, including three currently). You MUST follow the factory procedure EXACTLY. You didn't think that not having the correct plugs MIGHT be a problem?

 

I’m here because i didn’t know what was going on with the car. Therefore I ask people who may have some advice. (I’m certainly not a “mechanic”) You seem you want to harp on the things I don’t know,but that’s specifically why I’m here. I have learned a few things here that I was unaware of prior. For that,I’m appreciative. But I dont think I’m interested in anymore advice from you in particular. Thanks again.

 

this sounds like a reasonable route to go with. I’ll look into how much a new distributor would be to match the replacement carb vs going with the old one and having someone get it all fixed up. I appreciate your advice though. I’ll definitely research which one will make the most sense for this project.

 

I'm not harping on anything, but common sense usually would tell someone that if the replacement part doesn't connect the same way as the original, something isn't going to work. GM is not in the habit of installing unneeded parts just to reduce their profits. As for the CCC system, again, this is not something one can just twiddle with and get it to work. It is integrated with other systems on the car, like the distributor. If you don't want to get the correct carb and figure out how to get it adjusted, then your only other option is to completely remove the computer system and install a non-computer carb and distributor. That will also require the skill to properly jet the carb and set up the correct advance curve in the new distributor. Out of the box aftermarket parts will be set up for the generic 350 Chevy.

 

https://www.rockauto.com/en/catalog/...stributor,7108


This distributor will be essentially plug and play. I'm sure it'll have a real conservative timing curve but it will at least provide some advance and will be easy to tune with any of the HEI advance kits.

You could also replace the stock O2 sensor with a wide band 02 with an AFR guage to really tune the carb in tight.

Funny enough I drove an 85 cutlass through the winter one semester in college. The CCC stuff was butchered already so I swapped the carb as you did and actually put a points distributor in it. I had no money and it was in stock so in it went. It took some tuning but the car eventually ran good and got decent mileage. I'm guessing I'm in a pretty exclusive club of folks who swapped an hei for a points distributor...

 

Also post the carb part number. It'll be on the left side of the carb body on the secondary bore. We can look up the factory application and see how close it is. I'm going to guess it'll be off something bigger than a 307 so it'll be a little rich..

 

Just my opinion but I would start out by going back to the stock configuration. The car ran fine at one time and will run fine again with the original type setup. Either get somebody to rebuild your original carburetor or purchase a correct remanufactured one. Unless you are capable of doing the modifications and tuning needed to change everything over I think you will have more problems than it is worth. And finding anyone that will even work on a carbureted vehicle is going to be hard anyway. Never mind somebody who can actually tune it in a non stock condition.

Have you actually driven it at all ? How fresh is the fuel ?

 

Hard pill to swallow time- there was probably nothing much wrong with the original carb. I'm willing to bet it ran better than the current one.
It's an old car, so keep your expectations low, AND it's a 307. The only things worse are a 260 or Buick 3.8. Ask me how I know.

 

the car sat for an amount of years years before I got it,so it literally wouldn’t idle unless I was on the gas. (I wasn’t referring to how it drives or performs…just simply getting it to run) But a gentleman on here explained the computer system to me and I’ll be looking into having the original carb rebuilt. My goal in reaching out on here was to get the car road worthy. Not to increase performance or anything.

 

I have bypassed the fuel tank and it is getting fresh gas from a gas can. And yea,I plan take the original carb to the place that rebuilt my spare carb that I swapped onto it. I’m sure he’ll get it together for me. And I’d love to go back to the original setup due to it being less stuff I would have to buy. Old setup or new setup,I just wanted it running right.