Engine sudden rough idle

[WestCoastRegal]

Hey guys, got a 86 regal with a 3.8 and about 80,000 original miles and yesterday all of a sudden after driving and pulling into a shopping center and stopping at the stop sign, the engine started sputering badly where the car would shake with a rough idle all of a sudden but would go away when you pressed the accelerator, but even when you pressed the gas it would hesitate at first then it would go. Almost as if the engine wants to turn off. This happened all of a sudden and this is my daily driver. Any help will be GREATLY appreciated from you guys.

ok, this morning turned the car on and the idle went high like it always has and when it came back down the engine started with the rough idle again. by the time i rev it a couple times and pull it out the drive way the car seems to get better and the rough idle is gone, the 4 minutes down the road i come to a stop light and the engine has a reallyy rough idle. I take it to a shop and they find a gasoline leak from one of the main pipes going into the carburator in the front, so they said i was lucky it didnt catch on fire, so they fix the leak and still has a rough idle, so they change spark plugs and the roter and rotor cap. And it made the idle a tiny bit better but its still rough, they said a carb rebuild would fix the idle. But why would it do this all of a sudden and work fine for a few miles this morning? doesnt make sense to me. any help will be GREATLY appreciated.

 

[WestCoastRegal]

im very close to taking a sledge hammer to this car

 

[TurboBuRick]

Are we talking a GN here? What year?

Are you getting a check engine light?

 

[WestCoastRegal]

its a regular 86 regal. and no check engine light. And yes all the lights on the dash come on when the ignition is opened.

 

[TurboBuRick]

What motor? Is it a 3.8 turbo car?

 

[charlief1]

You've got a vac leak.

 

[WestCoastRegal]

no its a regular 86 regal with a REGULAR 3.8 engine, no turbo. Just a plain jane regal.

 

[WestCoastRegal]

and where do i start looking for a vacuum leak??

 

[charlief1]

Get a can of carb cleaner and while the engine is running spray around until the engine speed picks up or smooths out. Then look in the general area you were spraying.

 

[davidf]

Get a can of carb cleaner and while the engine is running spray around until the engine speed picks up or smooths out. Then look in the general area you were spraying.

What he said. Also if you have a good set of ears, you may hear a slight hiss also.

 

[kingots2004]

check the plugs also. if you dont find a vac leak

 

[WestCoastRegal]

Ok, turned the car on this morning and idle went high as usual for cold start and when it came back down it had a little rough idle, and so i sprayed the carb cleaner down the throat of the carb and it smoothed the idle for a few seconds and it would go back to rough, so i sprayed alot everywhere in the carb and it seemed to make the idle smooth, so i drove it for about 10 miles and the car was running perfectly, and then it had a tiny bit of rough idle by the time i got back home. So maybe it does need a carb rebuild???? Just put all new spark plugs on the car yesterday. The old ones werent too bad.

 

[fmster]

Change your gas filter while your at it,maybe you put bad gas or dirty gas.Happens all the time.

 

[WestCoastRegal]

how hard is it to change the fuel filter? How do i do that?

 

[fmster]

Gas filter is easy to change, is inside the carb in front follow the fuel line to carb.The filter is brass or paper 1inch or1 1/2 inch by 3/4 with a little spring.
Spray carb cleaner on inside of carb before you put new filter through the filter hole.All so check that the choke is not sticking.

 

[charlief1]

Very good point. I didn't think about bad gas. It's very possible that you have water in the gas. Does it seem to be using more fuel than usual?

 

[WestCoastRegal]

Fuel filter replaced and no difference.

 

[charlief1]

Have you checked for a vacuum leak yet?