problem identification and solution -- resolved. - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


General GM Chat When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made. Chat about all things GM (and related cars). Off-topic stuff should be in the Lounge, and all Model specific mechanical problems should be posted in the proper forum.

Reply
 
 
 
Thread Tools Search this Thread
Old 03-08-2007, 01:19 AM   #1
Junior Member
Thread Starter
 
Join Date: Sep 2002
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
jwakamud is on a distinguished road
Default problem identification and solution -- resolved.

ive noticed recently an annoyance. let me set it up.

when im idling [say, stopped at a light], if i push two window buttons [like, if i want to roll down both of the front windows at the same time] -> i feel a vibration come from the back of the car to the front of the car. i can do this on cue, at any time im stopped.

my brother says its causing a misfire because im overloading the alternator [i dont get the connexion]. but it seems to me, with my severely limited experience, that it has to be related to the alternator because its very clearly an electrical issue. or am i mistaken?

[the possibility im mistaken is why this is in general chat instead of electrical]
jwakamud is offline   Reply With Quote
Old 03-08-2007, 06:53 AM   #2
Senior Member
True Car Nut
 
Join Date: Oct 2002
Location: Groton, CT _NEBF 05, 06, 07_
Posts: 2,703
Thanks: 0
Thanked 0 Times in 0 Posts
markwb is on a distinguished road
Default

Simultaneous lowering or raising of two windows will place significant load on the electrical system, but shouldn't have adverse impact. You should be able to operate all four windows at once. I don't understand the vibration that is mentioned though.
markwb is offline   Reply With Quote
Old 03-08-2007, 07:14 AM   #3
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

The vibration may be caused by the alternator putting more of a load on the drive train as it supplies the power. You could have Autozone/Advance/PartsAmerica test the alternator for free and see if it passes the "stress" or load part of the test.

When your brother says misfire, have you actually seen a misfire from the engine or merely a lowering of the rpms for a moment?
BillBoost37 is offline   Reply With Quote
Old 03-08-2007, 08:49 AM   #4
Junior Member
Posts like a Ricer Type-R
 
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road
Default

A weak alternator can make a misfire worse, or bad enough to feel it. Not saying that'* your issue, but it can be related.

If the engine stumbles, the exhaust will shake. Your exhuast is a giant tuning fork. The stumble will cause a travelling wave that goes out to the mufflers, and returns.
willwren is offline   Reply With Quote
Old 03-08-2007, 08:54 AM   #5
Senior Member
True Car Nut
 
Join Date: Jun 2003
Location: Purgatory
Posts: 6,313
Thanks: 0
Thanked 0 Times in 0 Posts
PontiacDad is on a distinguished road
Default

I think your brother is right, when you load the alternator the voltage drops causing a miss fire. Do you have a voltmeter to see how much the voltage is dropping when you press the windows?
PontiacDad is offline   Reply With Quote
Old 03-08-2007, 11:53 AM   #6
Junior Member
Thread Starter
 
Join Date: Sep 2002
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
jwakamud is on a distinguished road
Default

thanks for the replies.

ill check out the voltmeter today.

on a related note, my lights dim very noticeably when i do this.
jwakamud is offline   Reply With Quote
Old 03-08-2007, 12:14 PM   #7
Guest
Certified GM nut
 
Join Date: Jul 2004
Location: West Point, Utah - Village Idiot
Posts: 1,606
Thanks: 0
Thanked 2 Times in 2 Posts
SSE Motorhead is on a distinguished road
Default

Don't forget to check the battery condition too. It works with the alternator.

Might check them battery cables for corrosion as well...
SSE Motorhead is offline   Reply With Quote
Old 03-08-2007, 12:42 PM   #8
Retired Moderator
True Car Nut
 
Pearl_bonnie02's Avatar
 
Join Date: Sep 2006
Location: Northwest Indiana
Posts: 3,047
Thanks: 0
Thanked 0 Times in 0 Posts
Pearl_bonnie02 is on a distinguished road
Default

Quote:
Originally Posted by jwakamud
thanks for the replies.

ill check out the voltmeter today.

on a related note, my lights dim very noticeably when i do this.
Hey Jwak,

Mine does that to. And all my other cars have done this also. I've looked at it as no biggie really. When the lights start dimming bad, then you know its time for a new alternator. IMO anyway.
Pearl_bonnie02 is offline   Reply With Quote
Old 03-09-2007, 01:52 AM   #9
Junior Member
Thread Starter
 
Join Date: Sep 2002
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
jwakamud is on a distinguished road
Default

yeah, im not concerned about the lights dimming. just thought id throw that in.

on my way to work today, i watched the DIC battery reading. reproduced the result, and the DIC dropped from 14.9 volts to 14.0 volts, then jumped right back up. verdict?
jwakamud is offline   Reply With Quote
Old 03-09-2007, 04:31 AM   #10
Senior Member
True Car Nut
 
Join Date: Aug 2003
Location: Salina, KS
Posts: 5,246
Thanks: 0
Thanked 0 Times in 0 Posts
TrueWildMan is on a distinguished road
Default

As Will said, it can make it worse. It'* worth checking to see if the low voltage didn't uncover a slight existing issue with your plugs/wires/coils. May as well check those, too.
TrueWildMan is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
My boss and I resolved things debra Lounge 3 07-18-2013 11:18 PM
RESOLVED! 95 SSEi S/C Start - Idle problem Taddduck 1992-1999 0 07-24-2009 04:08 PM
E-brake - found problem, need solution papilgee4evaeva 2000-2005 1 12-28-2008 11:18 PM
Stalling Problem (Resolved) bonneville2k6 1992-1999 4 08-27-2006 05:39 PM
Steering problem final solution... chili_1 2000-2005 8 02-28-2005 02:18 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 09:43 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.