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Car dies ALL the time.

  • Thread starter Thread starter cammngt
  • Start date Start date Sep 11, 2009

cammngt

New Member
Sep 18, 2007
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Houston, TX
Sep 11, 2009
#1
  • Sep 11, 2009
  • #1
Car seems to die all the time once I come to a stop or sometimes on initial start up. I thought I found the problem being a dryrotted Vaccum line that come from the back of plenum. Changed and seems to be idoling fine now, but I need to bump it up some.

My real question is, after the engine dies....why do my gauges sweep EVERY time I restart the car. I know that it mean the comp is reset or battery was un connected. Is this an issue somewhere in the wiring? Battery? Ignition switch??? I'm lost here. I am just unsure what would cause the gauges to sweep only when the car dies on it's own and not with the key.

Anything obvious to check?? I see no loose or unplugged connections, battery terminals ok, no loose fuses, no more vaccum leaks. No codes or CEL on either.

Thanks for the help.

2000 GT with Cold air, PP TB and plenum, Shorties, x-pipe, mufflers are all the mods done if it helps
 

RedDaemon

10 Year Member
Mar 31, 2005
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108
Atlanta, GA
Sep 11, 2009
#2
  • Sep 11, 2009
  • #2
when the car dies when coming to a stop or from an intitial start, this is usually a symptom of a bad IAC. Clean or replace it and your problems will mostl likely go away.
 

cammngt

New Member
Sep 18, 2007
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Houston, TX
Sep 11, 2009
#3
  • Sep 11, 2009
  • #3
would that make the RPM's come back down really fast?? Like in between shifts. or cause the idol to surge up and down pretty quick at idol??
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
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108
Atlanta, GA
Sep 11, 2009
#4
  • Sep 11, 2009
  • #4
Like in between shifts. or cause the idol to surge up and down pretty quick at idol??
Click to expand...

yes

cammngt said:
would that make the RPM's come back down really fast??
Click to expand...

quite possible. a few things could cause this i would imagine.
 

cammngt

New Member
Sep 18, 2007
20
0
0
Houston, TX
Sep 11, 2009
#5
  • Sep 11, 2009
  • #5
I will replace this weekend.

But....I don;t see what effect that has on makeing the gauges sweep if the IAC is causing the car to die
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
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Sep 11, 2009
#6
  • Sep 11, 2009
  • #6
Guage sweep is most likely a problem with charging system. You possibly have two separate issues.

Check battery terminals and take the car to AutoZone and have them test the charging system in the parking lot for free.
 
H

HOOCBB

New Member
Jun 5, 2008
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Sep 11, 2009
#7
  • Sep 11, 2009
  • #7
The gauge sweep has nothing to do with the IAC. I believe when turning the key to start, it removes power from the dash in an attempt to ensure the starter gets enough power to turn the engine over.

Next time you get in your car, turn it on (without starting). Turn the radio on, then start the engine. I bet your radio turns off when cranking, but comes back on when the key returns to the run position.

I'm not 100% on that as I have not had mine die on me in a couple of months.
 
T

tradde

New Member
Aug 2, 2005
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Pennsylvania
Sep 11, 2009
#8
  • Sep 11, 2009
  • #8
I don't know if this could be related, but will offer it up as it happened to me.
I had an 85 Capri that would sometimes just start to die, usually on a corner, but sometimes not. Took me awhile to figure out it was a bad ignition switch that on a slight pull on the top of the steering column would start to pull
apart and cause the car to stall. Replaced switch, and all was well again.
And it was an easy fix. Looking at the old switch you cold see that it
could easily separate and pull connections apart. Hope this helps in some
way. It does seem to be something other than IAC to me.
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
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108
Atlanta, GA
Sep 11, 2009
#9
  • Sep 11, 2009
  • #9
Kilgore Trout said:
Guage sweep is most likely a problem with charging system. You possibly have two separate issues.

Check battery terminals and take the car to AutoZone and have them test the charging system in the parking lot for free.
Click to expand...

+1
 

trombonedemon

Well-Known Member
Jun 25, 2009
1,962
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59
U.S.A, U.S.A., U.S.A.!
Sep 11, 2009
#10
  • Sep 11, 2009
  • #10
Your car's computer is smarter than what people is giving it credit for, your car knows that you did not turn it off manually. Its just a fail safe sweep of some type. OBD2 is awsome its not a problem. You can do a manual sweep by holder the button on your car gauges when you turn the key. No worries. Now if it does that when you start your car when it didn't die then you might have battery or battery terminal problem. Know thye car and your car will know you, its true.
 
R

rconaway

Founding Member
Nov 11, 1999
1,415
3
39
Phoenix, Az.
Sep 12, 2009
#11
  • Sep 12, 2009
  • #11
I had a similiar problem when coming off a freeway or just from a steady state throttle position. We never really solved the problem directly since we did a lot of other work right after it cropped up. However, assuming it's not a computer programming problem, I would look for the following:

Pull the codes and make sure there is nothing there
Clean the IAC
Make sure the throttle is closing all the way
Check the air filter and possible clean the MAF sensor
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Sep 12, 2009
#12
  • Sep 12, 2009
  • #12
rconaway said:
I had a similiar problem when coming off a freeway or just from a steady state throttle position. We never really solved the problem directly since we did a lot of other work right after it cropped up. However, assuming it's not a computer programming problem, I would look for the following:

Pull the codes and make sure there is nothing there
Clean the IAC
Make sure the throttle is closing all the way
Check the air filter and possible clean the MAF sensor
Click to expand...

this to me almost sounds like a different issue that ive seen with our cars. ive seen multiple threads about our cars dying right when theyre getting off the freeway (usually when you depress the clutch) and/or when you go over a bump in the road. is your car manual?
 
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