Oldsmobile cutlass supreme 1980, cant go over 15mph

[78Delta88]

What tools do you have? You need to base line.

Minimum replace you fuel pump it's garbage. Then clean the carburator, get new fuel filters toss the old ones.

Research how a choke works. The engine is an air-pump. Choke it off and it can't breath. Choke closes to start and slowly opens to full open as engine heats up. You set the choke by closing on a 1/16 inch drill bit. That is begining setting and you open that gap over time to a max of 1/8 inch. Any more than that and something is out of balance.

 

[78Delta88]

Next find your firing order and trace all the wires to make sure they are hooked up correctly.

Put your foot on the brake and rev to 1200 and hold it, does it shake and shutter, does it run rough or smooth?

With your foot on brake put in drive hold down on the brakes so car can't move. Now from idle stab the gas to the floor. Does it speed up, bogg down, shudder or shake, or back fire?

 

[mickeypowa]

Hi!
My firing order is ok I just checked.

What is the problem with my fuel pump ? Why is it garbage ? What type of fuel pump do you recommand ? I replaced it few years ago.

Thanks

Mickey

 

[L05edSS]

when was the last time you rebuilt your carburetor?

yeah i was thinkin bad accelerator pump.

 

[Kra5379]

Hi guys!

Thanks a lot for your help.
Actually the engine is an oldsmobile 350 from a 74 oldsmobile I guess.

I did new tests with new spark plugs and cleaning and rising a little bit de idle speed by turning the screw. It was better, I was able to drive at maybe 50 mph on flat road but no power when I go uphill ! But I was able to drive home!

The carburetor is a holley 4776, I just bought the rebuild kit, new spark plug wires and new spark plugs because I noticed the UR4 are for chevy, the oldsmobile blocks need XR4 actually ! I also bought a new gasoline filter And air filter.

Can't wait to test all that. I will keep you in touch and thanks again !

Mickey

If I had a nickel for every pre-1977 350 Oldsmobile that ended up being a 1977-1984 260, 307, or 403…Better start by running your casting numbers so you know what you actually have.

 

[78Delta88]

Quality of parts not what they used to be. Your FP gauge jumps around too much

 

[78Delta88]

From Olds Junction

 

[mickeypowa]

If I had a nickel for every pre-1977 350 Oldsmobile that ended up being a 1977-1984 260, 307, or 403…Better start by running your casting numbers so you know what you actually have.

Castings numbers on the block :
395558 2

On google it says 68-76 350 oldsmobile 😁

 

[78Delta88]

Yep 350

 

[Kra5379]

Castings numbers on the block :
395558 2

On google it says 68-76 350 oldsmobile 😁

If the Casting number is 395558 then Google is wrong again. It’s a 1968-1970 350 block. I’ll go out on a limb and say it’s a 1969 since the first digit 3=Oldsmobile Division and the second = Year manufactured (9-1969, 0-1970, 1-1971, etc)