I have 2 Oldsmobile’s
a 85 delt coupe and a 84 regency coupe. Both 307s both CCC. The delt runs perfect. the regency I just bought and it’s not running right. The fuel pump quit and I replaced it but it’s still running like it’s starved for fuel. Could I take the carb off the delt and put it on the regency to troubleshoot if I’m having a problem w the carb or should I leave the delt alone since it’s running good. I’m under the impression tht the computer controls the mixture on these cars so if I took it off the delt and put it back on would it adjust itself where it needs to be?

 

Yes I think you can swap the carburetors for test purposes; but, I wouldn't yet because almost every time something is R&R'd something else gets broken or twisted and because there are other more likely areas to check first.

1.) Change the fuel filter,
2.) Check the rubber hoses at the tank for cracking,
3.) Drop the tank to look at the pre-filter/sock, and
4.) Swap fuel pumps as a test or pressure and flow test the new one.

What are the symptoms?

Good luck!!!

 

I forgot to mention i changed the fuel filter when I did the pump. It’ll start and idle fine but when u hit 45 it starts to bog down or up hill it loses power real bad

if the rubber hoses hoses at the tank were cracked would there be a gas leak or not necessarily?

 

I forgot to mention i changed the fuel filter when I did the pump. It’ll start and idle fine but when u hit 45 it starts to bog down or up hill it loses power real bad

That could be a plugged catalytic converter, can you hear a moaning sound on the RF floor.

If the rubber hoses hoses at the tank were cracked would there be a gas leak or not necessarily?

Yes the cracks would allow in air instead of pulling fuel toward the engine without seeing an obvious outward leak.

Good luck!!!

 

Is there a check engine light? Is the stock catalytic converter still on it? Does it almost stall at a light? There could be an issue like a stuck on lock up torque converter or plugged cat. Also a timing check by grounding the B? terminal, the tan wire needs disconnected to disable the computer advance, is a good check as well. The 307 is no powerhouse, if anything is off, it feels sluggish in a big car especially.

 

Definitely check to see if there are any stored codes. Auto parts stores used to do this for free but I'm not sure if the parts monkeys would know how to check a GM type 1 computer for codes.

Here's a good thread:

https://classicoldsmobile.com/forums...stions-149168/

 

Once again, the CCC carb must be adjusted on the specific engine following the procedure in the CSM EXACTLY. Fail to do this and you'll just be chasing your tail. That involves setting the idle mixture screws while monitoring the mixture control solenoid duty cycle with the system in closed loop mode. No, there is no guarantee that a carb adjusted for one 307 is properly adjusted for another. Even worse, the 84 is a flat tappet cam 307, likely with a two-point adjustment solenoid. The 85 is a roller cam 307 with a three point adjustment solenoid. Those two carbs are not the same internally.

 

Thanks Joe for the clarification on the carbs. Another member recently had a stuck heat riser/flap in the exhaust manifold, that would be worth checking.

Good luck!!!