2004 chevy impala, rough idle

40

Asked by Jul 04, 2016 at 02:07 PM about the 2004 Chevrolet Impala LS

Question type: Maintenance & Repair

I have a 2014 chevy impala. It has started with this
rough idle here lately. And while driving it will jerk a
little. And during acceleration it seems to hesitate
and jerk a little bit. I've replaced the plugs, wires,
fuel filter, fuel pump, crank shaft position sensor,
mass air flow sensor and I don't hear a vacuum
leak. Any suggestions on this would be greatly
appreciated. Thank you.

9 Answers

65,905

If this is a '14 model it was still covered by the new car warranty unless you have over 36,000 miles on it. If it's an '04 model, is the check engine light on? If so, have the computer scanned and post the trouble codes here. Most auto parts stores will do it for free. HTH. -Jim

40

It's a 2004. The problem has been going on for about 2 weeks. The check engine light came on. Had it scanned. 0455, evap leak large. So replaced the cap and the vent solenoid. And the light went off. But it still has the rough idle. Don't want to keep replacing parts blind. What about the purge valve or the throttle position sensor

1 out of 1 people think this is helpful.
65,905

Check your vacuum hoses, paying close attention to the EVAP system lines. Keep your gas tank between the 1/4 and 3/4 marks to try to get the computer to run diagnostics on the EVAP system again. That's the hardest one to do. Sounds like a vacuum line is disconnected or the purge valve is stuck open. If you have raw fuel in the vacuum line at the throttle body, purge valve is malfunctioning and dumping raw fuel into the throttle body. However the purge valve should trigger the check engine light and a different trouble code should set. HTH. - Jim

40

Just changed the purge valve. No difference. I guess I need a smoke test on the vacuum lines. I don't hear any hissing. I'm stumped.

1 out of 1 people think this is helpful.
65,905

At this point, I agree. A smoke test will find any leaks, large or small. Please keep us posted. - Jim

40

Definitely.

1 out of 1 people think this is helpful.
40

And thank you for the help.

1 out of 1 people think this is helpful.
65,905

You're welcome. Glad to help! -Jim

I have an 03 impala and it's exhibiting the exact same symptoms it's a rebuilt trans with about 5k miles and the motor has about 114k it was running just fine till a few days ago I did recently cut the cat and straight pipe it so idk if that has anything to do with it

Your Answer

Add photo

Related Questions

Impala

Looking for a Used Impala in your area?

CarGurus has 31,465 nationwide Impala listings starting at $799.

ZIP:

Search Chevrolet Impala Questions

Chevrolet Impala Experts

#1 Js08016
Js08016
Reputation 1,760
#2 Danny Wang
Danny Wang
Reputation 1,640
#3 Tom Demyan
Tom Demyan
Reputation 1,570
View All

Related Models For Sale

Used Chevrolet Malibu
915 Great Deals out of 79,357 listings starting at $1,500
Used Honda Accord
821 Great Deals out of 85,701 listings starting at $988
Used Chrysler 300
400 Great Deals out of 19,918 listings starting at $1,000
Used Nissan Maxima
296 Great Deals out of 25,094 listings starting at $999
Used Ford Mustang
454 Great Deals out of 45,520 listings starting at $1,999
Used Buick LaCrosse
212 Great Deals out of 21,531 listings starting at $1,100
Used Nissan Altima
1,025 Great Deals out of 80,832 listings starting at $1,995
Used Toyota Camry
1,012 Great Deals out of 90,766 listings starting at $650
Used Chevrolet Tahoe
566 Great Deals out of 28,765 listings starting at $1,699
Used Chevrolet Silverado 1500
1,686 Great Deals out of 174,330 listings starting at $1,250

Used Cars For Sale

2017 Chevrolet Impala LS For Sale
1,729 listings starting at $19,700
2016 Chevrolet Impala LS For Sale
6 Great Deals out of 556 listings starting at $14,893
2015 Chevrolet Impala LS For Sale
343 listings starting at $10,856
2014 Chevrolet Impala LS For Sale
3 Great Deals out of 324 listings starting at $10,499
2013 Chevrolet Impala LS For Sale
33 listings starting at $7,700

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.