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PLEASE HELP!

  • Thread starter Thread starter 92greenlx
  • Start date Start date Jul 15, 2004
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92greenlx

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Mar 27, 2002
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Jul 15, 2004
#1
  • Jul 15, 2004
  • #1
I believe I have a Vacum leak. My car idles choppy like I have a Cam but all I have is the stock one. My exhaust smells the worst it ever has and thats even with the high flow cat h-pipe. It smelled 100 times better with my old off road one. Also, when I let off the gas my brakes get hard. So dont I need vacum for my brakes? And when I 1st start it for the day it dies right away as if the car needs to warm up and the idle bounces. Then it hangs at like 1500 sometimes at 2000 rpm while slowing down to a stop!
Please help me out here! What can I check or do to try and fix this problem? I am ready to take it to the dealership around the corner because I cant figure this thing out!
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 16, 2004
#2
  • Jul 16, 2004
  • #2
have you pulled codes?
vac on a near stock motor should be 15-20 inches at idle.
your symptom sound like a vac leak. the brake booster should be related (or the booster took a poo at the same time).

grab vac off the vac tree and let us know. ditto for codes.

good luck.
 
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92greenlx

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Mar 27, 2002
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Jul 16, 2004
#3
  • Jul 16, 2004
  • #3
How do I grab vac off the vac tree? Also, I looked under my hood for any obvious vac leaks and I found the small line that comes from the passenger side firewall and connects to the piece on the drivers side firewall busted.
 

dastang2

Active Member
Dec 11, 2003
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tx
Jul 16, 2004
#4
  • Jul 16, 2004
  • #4
if you pump your brakes fast and about 5 or 6 times and your idle starts to either rise or drops, then your booster is bad. i have heard this works
 
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92greenlx

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Mar 27, 2002
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Jul 16, 2004
#5
  • Jul 16, 2004
  • #5
I will try that out. I bought a new Temp Sensor just in case that is part of my other problems.
 
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BlazerLT

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Jun 26, 2004
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Jul 16, 2004
#6
  • Jul 16, 2004
  • #6
EGR valve stuck open with carbon?
 
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92greenlx

Founding Member
Mar 27, 2002
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Jul 16, 2004
#7
  • Jul 16, 2004
  • #7
I was thinking it might be that as well. But would that also cause the nasty exhaust fumes? I have had a vacum leak before and it made my exhaust smell bad. But that leak was easy to find. I cant find this one. I just changed out my Temp Sensor while having the negative battery cable disconnected. I started up the car and it turns over right away nicely then the idle goes down and it dies. The 2nd crank it did it again. So on the 3rd crank I gave the car some gas and it stayed running.
 
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blk92stangg

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Jan 30, 2004
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Jul 17, 2004
#8
  • Jul 17, 2004
  • #8
If it IS a vacuum leak, Ill bet you 20 bucks it's the vacuum line under the intake, or the hoses that extend from under the intake to the smog box. I take paypal btw.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 17, 2004
#9
  • Jul 17, 2004
  • #9
again, i would pull codes and check your vacuum. dont guess at it. the IAC is hard to check with a meter, so just clean it.
good luck.
 
J

Js5ohLX

Member
Apr 5, 2004
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Jul 17, 2004
#10
  • Jul 17, 2004
  • #10
To affect your brakes, you have a massive vacuum leak, check the pcv, or the line going to the breaks, have you had the upper intake off lately?
 
9

92greenlx

Founding Member
Mar 27, 2002
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Jul 17, 2004
#11
  • Jul 17, 2004
  • #11
Last time I had a leak it was from the hose under the stock upper intake that goes to the box. But I now have a GT40 intake on. I dont remember if there is a line under the upper intake on the gt40. The intake swap was done about a year ago by my buddy and brother while I was overseas. This all started recently and its getting worse. 1st it started with just the check engine light coming on when I accelerated hard then let off the gas. Now all of this. What exactly is my IAC and how do I clean it.
 

The Shape

Founding Member
Jan 11, 2002
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East ARKANSAS Delta
Jul 17, 2004
#12
  • Jul 17, 2004
  • #12
The IAC is the little cylinder shaped object on the side of your throttle body it is held on with two bolts. Just pull it off and clean it out really good with throttle body cleaner and some Q-tips. Also wouldn't hurt to do the same to your EGR. But if you are getting a CE light the first thing to do would be pull the codes. You can pick up a cheap code reader for about 20 bucks at wal-mart or autozone will run the codes for you for free.
 
9

92greenlx

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Jul 17, 2004
#13
  • Jul 17, 2004
  • #13
OK......I found a disconnected hose on the black box just like blk92stangg said. Same area as my last leak. It is a little bit better now. But I still have a litle bit of an idle problem. When I slow down for a stop light or sign, the rpms hang at like 2000 then to 1500 and then after a few seconds its normal again. The check light comes on and off while just crusing as to where before it only came on when going down the highway after hitting the gas hard and then getting off of it. So I now have the car sitting in the garage with the battery cables disconnected. In a lil while I will start it back up and see how things are headed and go from there.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 17, 2004
#14
  • Jul 17, 2004
  • #14
hanging idle sounds like a vac leak still. if you have a gauge, check it. see one of my above-posts for specs.
good luck.
 
9

92greenlx

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Mar 27, 2002
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Jul 17, 2004
#15
  • Jul 17, 2004
  • #15
Thanks for the info HISSIN!
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 18, 2004
#16
  • Jul 18, 2004
  • #16
92greenlx said:
Thanks for the info HISSIN!
Click to expand...
no, you can thank us when it is fixed.
good luck.
 
9

92greenlx

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Mar 27, 2002
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Jul 20, 2004
#17
  • Jul 20, 2004
  • #17
OK.......I found 2 vaccum leaks. They are fixed now. I also set my timing to 12 deg and set my idle best as possible. So now the only problem I have is the cold start and the somewhat hanging idle. The hanging idle is still there but not as bad now. So looks like the next thing I will be doing soon is cleaning out the IAC and the EGR.
 

dastang2

Active Member
Dec 11, 2003
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tx
Jul 20, 2004
#18
  • Jul 20, 2004
  • #18
spray some starting fluid around the engine while running to see if it revves up, if so you have a leak somewhere close
 
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92greenlx

Founding Member
Mar 27, 2002
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Jul 26, 2004
#19
  • Jul 26, 2004
  • #19
I installed a new IAC. Next is a new EGR. I will try out the starting fluid test.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 26, 2004
#20
  • Jul 26, 2004
  • #20
i would test the EGR before blindly replacing it. the valve can get coked up, and the solenoid can take a dump (wiring, etc can go bad, but i think the two i listed are most likely).

just my thoughts. good luck.
 
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