ruff idle

[Murfthesurf]

Hey guy,s i have a 1987 buick regal with a rebuilt motor 3.8L new carb.if my car idles to long my check engine light comes on.Once i pull off in a couple of minutes it goes away .Before i got my engine rebuilt it did the same thing.Do i need to change my coumptuer? it also idles ruff.It was a hassle at the Woodward Dream Crusie.

 

[MrSony]

Probably a vacuum leak. These cars had 100s of little vacuum lines that dry rot and split. Nice car. Also, it's considered polite to introduce yourself. Welcome to the forum. You said your engine was rebuilt... is everything plugged in?

 

[Wageslave]

Hey guy,s i have a 1987 buick regal with a rebuilt motor 3.8L new carb.if my car idles to long my check engine light comes on.Once i pull off in a couple of minutes it goes away .Before i got my engine rebuilt it did the same thing.Do i need to change my coumptuer? it also idles ruff.It was a hassle at the Woodward Dream Crusie. View attachment 72394

You might check your ignition. If it has a rough idle, it is probably reading rich at the O2 sensor. Too long and it may be triggering a CEL.

You may want to check your distributor cap and rotor for wear. Then check your plugs and wires.

Ditto for the vacuum lines. If that doesn't work check back in and we can try something else.

 

[Jeff L]

Find out what trouble codes were set when the check engine light came on.

 

[pontiacgp]

Did you remove and install the engine or did the shop who rebuilt it do it? Also when and who installed the new carb. If the shop did it all then they have the obligation to make sure it was running right before they returned the car to you.

 

[Clutch]

Greetings from dirty Jersey you'll find your answers here

 

[fleming442]

I'd try an O2 sensor before the ECM.

 

[Murfthesurf]

Probably a vacuum leak. These cars had 100s of little vacuum lines that dry rot and split. Nice car. Also, it's considered polite to introduce yourself. Welcome to the forum. You said your engine was rebuilt... is everything plugged in?

Hi ,guy,s i'm Mike. I'm from Detroit Mi.I work for GM.Thank,s for all the info. You guy,s are great!.I've seen this site before but never joined until now.I'm going to check vacuum hose,s.If that don't work I will take it back to the shop where they did the work.Thank,s again and great to meet ya'll

 

[565bbchevy]

Sorry in advance.

 

[airboatgreg]

When car is idling rough spray a little carb cleaner in intake or put you hand over carb blocking air. If it idles good then you have a lean condition which I suspect. Make sure you have the correct AC Delco PCV valve installed (as others will have one number that covers ten Delco') and check for vacuum leaks by pinching vacuum hoses one at a time. With new engine properly re-torque intake bolts. Adjust carb air/fuel screws if need be. If that doesn't work swing by house next weekend and we'll look at. Can't today as back is jacked