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Anyone have a problem with the rpms hanging sometimes? Even has high as like 3k?

  • Thread starter Thread starter Pokageek
  • Start date Start date Oct 16, 2005

Pokageek

Active Member
Jun 10, 2005
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MA, USA
Oct 16, 2005
#1
  • Oct 16, 2005
  • #1
And sometimes I am cruising and the car pulls itself along without me hitting the gas pedal. I put it in neutral and it stays at whatever RPM until I hit the gas again and then it comes back down.
 

CManT1914

New Member
Feb 5, 2004
3,172
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0
Killeen, Texas
Oct 16, 2005
#2
  • Oct 16, 2005
  • #2
That could be anything from a vacuum leak, to a faulty TPS, to a sticking throttle blade.
 

1994Vib.RedGT

Member
Aug 19, 2004
585
0
16
Denver, CO
Oct 16, 2005
#3
  • Oct 16, 2005
  • #3
i had this problem once, and mine was the throttle body stop screw was not holding its place, and tightening itself down, opening the butterfly more and more as it did, i just put some locktight on it and problem solved
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Oct 16, 2005
#4
  • Oct 16, 2005
  • #4
The prob might even be your ISC or IAC or whatever you wish to call it.

You know ............ that little thingie connected to your throttle body.

Maybe you ought to try and give it a good cleaning.

Grady
 

Pokageek

Active Member
Jun 10, 2005
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Oct 16, 2005
#5
  • Oct 16, 2005
  • #5
That's the weird thing. I have a NEW Ford Racing 65mm TB that comes with all those components. This did not happen until I removed my smog pump though.

"i had this problem once, and mine was the throttle body stop screw was not holding its place, and tightening itself down, opening the butterfly more and more as it did, i just put some locktight on it and problem solved"

This could be it. Thanks for the suggestions. I will try. (checked vaccum leaks and couldn't find any).
 

CManT1914

New Member
Feb 5, 2004
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Killeen, Texas
Oct 17, 2005
#6
  • Oct 17, 2005
  • #6
Pokageek said:
That's the weird thing. I have a NEW Ford Racing 65mm TB that comes with all those components. This did not happen until I removed my smog pump though.
Click to expand...

I can almost guarantee that it's a vacuum leak then. There's a couple vacuum lines that run to the smog pump hoses, those are probably leaking somewhere. Mine were, but they had holes in them back in the loom where you couldn't see them untill I took the whole harness off. Look at those hoses very carefully.
 

Pokageek

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Jun 10, 2005
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Oct 17, 2005
#7
  • Oct 17, 2005
  • #7
I removed those hoses but maybe there is one still somewhere. I will check.
 

CManT1914

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Feb 5, 2004
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Killeen, Texas
Oct 17, 2005
#8
  • Oct 17, 2005
  • #8
Pokageek said:
I removed those hoses but maybe there is one still somewhere. I will check.
Click to expand...

Awesome, you remembered to plug the holes they came from with something right?
 

Pokageek

Active Member
Jun 10, 2005
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Oct 17, 2005
#9
  • Oct 17, 2005
  • #9
I don't think you realize. I pulled all that **** out. I am pretty sure it was 9/16 bolts inthe back of the engine and then the exhaust tube on the h pipe.. I honestly dont remember anymore holes other than 2 sensors.
 

Chowder Head

Member
Dec 30, 2003
155
0
16
Tampa, FL
Oct 18, 2005
#10
  • Oct 18, 2005
  • #10
Now that you mention it, when I start my car up and give it a little rev, it seems slow going back to 1k.

Anyone know what this means? There are no other rpm related problems.
 

CManT1914

New Member
Feb 5, 2004
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Killeen, Texas
Oct 18, 2005
#11
  • Oct 18, 2005
  • #11
Pokageek said:
I don't think you realize. I pulled all that **** out. I am pretty sure it was 9/16 bolts inthe back of the engine and then the exhaust tube on the h pipe.. I honestly dont remember anymore holes other than 2 sensors.
Click to expand...

Yea I know what you mean. You plugged the holes in the back of the heads and on the h-pipe. But on the actual hoses, there are two valves (not sensors) that have small vacuum lines coming off them and running into the fender. One is green, the other either gray or brown, don't remember for sure. But these vacuum lines have to be capped off as well, NOT just the holes in the heads and h-pipe. I think we are misunderstanding each other. I just want to make sure you got the vacuum lines capped off too.
 

Pokageek

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Jun 10, 2005
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Oct 18, 2005
#12
  • Oct 18, 2005
  • #12
Ahahah!! No I did not cap them. I thought they were sensors! I will try this CMan, thank you.

"Now that you mention it, when I start my car up and give it a little rev, it seems slow going back to 1k.

Anyone know what this means? There are no other rpm related problems."

This is a usual problem for our cars. There is a IAC plate that resolves problems with airflow that ruben.olivencia@us.army.mil makes. He is on this site. Here are his comments.

"Should work fine as long as the IAC has restricted airflow. A copper cap (with a drilled restrictor hole) in the hose going to the IAC will make it work also.

$7.50 shipped and money back is not satisfied."
 

CManT1914

New Member
Feb 5, 2004
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0
Killeen, Texas
Oct 18, 2005
#13
  • Oct 18, 2005
  • #13
Pokageek said:
Ahahah!! No I did not cap them. I thought they were sensors! I will try this CMan, thank you.
Click to expand...

Awesome dude!! I had a feeling you hadn't capped those, or capped them properly. I thought I had gotten mine capped off good, but it turns out they had fallen against the header and melted them below the caps, so I had to cut them back and recap them. Good luck bro!!
 

Pokageek

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Jun 10, 2005
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Oct 19, 2005
#14
  • Oct 19, 2005
  • #14
Thanks. I used zip ties on them so they shouldn't hit the header. I was also wondering with my EGR leak, if that could cause surging..Hmm.. I wonder if that is considered in the category of exhaust leak or vacuum leak..or both?
 

CManT1914

New Member
Feb 5, 2004
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Killeen, Texas
Oct 19, 2005
#15
  • Oct 19, 2005
  • #15
Pokageek said:
Thanks. I used zip ties on them so they shouldn't hit the header. I was also wondering with my EGR leak, if that could cause surging..Hmm.. I wonder if that is considered in the category of exhaust leak or vacuum leak..or both?
Click to expand...

Exhaust leak, and that won't help anything either. Fix that while you're there.
 

Pokageek

Active Member
Jun 10, 2005
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Oct 20, 2005
#16
  • Oct 20, 2005
  • #16
Cman, yo uare going to laugh at this one. I think when I put the new intake on, the fuel lines may have been interfering with the actual physical movement of the throttle cable causing it to do this. I will test tomorrow after I plug in my tweecer and remove the EGR.
 

CManT1914

New Member
Feb 5, 2004
3,172
2
0
Killeen, Texas
Oct 20, 2005
#17
  • Oct 20, 2005
  • #17
Pokageek said:
Cman, yo uare going to laugh at this one. I think when I put the new intake on, the fuel lines may have been interfering with the actual physical movement of the throttle cable causing it to do this. I will test tomorrow after I plug in my tweecer and remove the EGR.
Click to expand...

LMAO, lemme know what you find.
 
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