2004 Buick Century GM 3.1 stalling and rough idle

Video shows procedure to clean idle air control valve, replacement of a leaking vacuum line. It was also necessary to thoroughly clean the throttle body plate and tunnel to improve the idle and eliminate the stalling. For the rest of the story see the follow-up video at • 2004 Buick Century 3.1...

[@williamdon3442]

All these 3100 gm engine videos proved so useful to me. I’m in Canada and it’s -30 -35 and not very fun pulling wrenches my 02 century starts idles but when I put it in gear to move forward it just bogs and I have to slowly apply throttle and it eventually gets up to speed. Done the plugs, fuel pressure regulator next I’m going to do the fuel pump(it has that easy access from the trunk) so happy for that

[@diywithdave3186]

Thanks for your comment. Glad it helped.

[@greglawson8001]

I have the same issue mine's egr insufficient follow p0401 code

[@louisgarris9435]

check the injectors easy fix / wont run right if one gets lazy it drove me nuts/ changed all 6

[@adamdefibaugh9674]

I was planning on doing mine after the fuel pump installation just be safe, then I'll do the fuel rain sensor.

[@JasonKale]

My idle was erratic sometimes would idle really high in traffic and Id have to restart the car and it would settle down. I was thinking it was this idle sensor but it always looked ugly to get to. I just cleaned the mass air flow sensor and throttle body plus the air filter and will see if that does the trick. Of course this morning before I cleaned the MAFS the car seemed to idle fine but Ill see later today.. A lot of people have had good luck just cleaning MAFS. I used cheapo walmart cleaner and not the CRC stuff as they were out of it. But thanks for the video because this is my next step if the high idle comes back.

[@adamdefibaugh9674]

The hole he is talking about is located under the bracket that holds the coil packs. Unbolt the bracket to safely reinstall the negative emissions pipe. Careful now, as it's made of plastic, and will break just as easily as the positive emissions pipe.

[@ratagris21]

Best thing to do is take off the throttle body and clean it thoroughly especially the back side as the accumulation affects it more than the front. May as well replace the gasket too while you're at it.

[@diywithdave3186]

Thanks for the tip.

[@michaelgarcia9362]

Thanks for your help

[@bronzebullet8640]

Omg my Buick is doing the same thing, I hope this works for mine too.

[@diywithdave3186]

Thanks for your comment.

[@stephenhebard7558]

Where is the plug for a code reader on an 03 Century?

[@diywithdave3186]

On the bottom edge of the dash by the driver's knees.

[@adamwarner5433]

Or could definitely b a clogged catilatic converter for having to press gas pedal down slow ,same issues and was my problem

[@diywithdave3186]

Thanks for sharing that info.

[@alexdergacheff8135]

My 2005 Buick century seems to idle a little rough but idles better when the AC unit is on. Also, I can hear a slight knocking noise when idling. Any ideas? Thanks!

[@diywithdave3186]

I don't know if you have checked for trouble codes. Mine still has a P0300 misfire code. It seems to be mainly on cylinder 5. When it idles the misfire gets worse. When it is running at higher RPMs it does not misfire as much. I have tried to swap spark plug wires between cylinders, with no difference. It could be a bad ignition coil, spark plug, or a vacuum leak on that cylinder. In your case with the additional load of the engine from the A/C unit it might be taking it out of the window where it is more likely to misfire. I guess you have to decide if it is bad enough to start trying to eliminate things.

[@alexdergacheff8135]

There's no check engine light on. I just purchased a scanner tool off amazon. Creader 3001. Will this show any faults in the car if there's no engine light on?

[@diywithdave3186]

Not all codes will illuminate the check engine light, but if you have the misfire p0300 code that I was talking about, it will. So it might show some codes, but they may not be related to your rough idle condition.

[@louisgarris9435]

check out the belt pully system i thought my buick was on its deafh bed an it was the harmonic balancer/now i beat it every day/flyin out my drive way like batman

[@2cents186]

Same problem Alex did you ever figure it out?

[@keithzeykon9428]

Camera a little closer next time

[@diywithdave3186]

Thanks for the feedback.

[@JustinSmith-hr6qg]

Have you ever changed thermostat in that car? I’m having an awful time changing mine.

[@diywithdave3186]

Yes, I just changed mine a couple of weeks ago. Check out this video kzbin.info/www/bejne/kJiviIVnmaiLiK8 . I did not make one because I thought his was pretty good. I did not need the funny shaped wrench that he used. I loosened that screw on the black bracket that holds the cables to the throttle body, that helped a bit with getting to the thermostat.

[@sonny2435]

with 3.1's, they're hidden and obstructed; there is a special angled tool--saves you from removing half the fuel inj. ( also on the 3.4's )

[@diywithdave3186]

@@sonny2435 thanks for your comment.