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Surging Idle checklist: Vacume Hoses

  • Thread starter Thread starter dirty slut
  • Start date Start date Dec 6, 2005
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vristang

15 Year Member
Mar 31, 2005
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Seattle
Dec 12, 2005
#21
  • Dec 12, 2005
  • #21
dirty :taco: said:
Well, The car has had a "Check Coolant" light on since I bought it and the car never fully warms up (I thought this was a good thing, I guess not). The previous owner told me that the cap needed replaced. 50resto has them for $30somethin bucks including the sensor. So I guess im gonna replace the thermostat first, then the sensor & cap, then Ill try the spacer fix.
Click to expand...

Before you buy a new overflow cap/sensor, try cleaning up the metal tips on the end of the sensor. Over time they get dirty and fail to function.

good luck
 
D

dirty slut

New Member
Nov 12, 2005
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Dec 12, 2005
#22
  • Dec 12, 2005
  • #22
vristang said:
Before you buy a new overflow cap/sensor, try cleaning up the metal tips on the end of the sensor. Over time they get dirty and fail to function.

good luck
Click to expand...

I just unplugged the sensor and the light went off. That new cap and sensor was more like $60 somethin. So im gonna do a readiator flush, put all new hoses on it, new thermostat and radiator cap and hope that it is good to go (the previous owner never did that stuff and he had it 2 years). Then Ill just keep an eye on it to see if its leakin coolant or what

As far as the IAC spacer thing I ordered it 2day and they said it should be in tommorrow, so Ill try to pick it up after I change the tranny mount
 

vristang

15 Year Member
Mar 31, 2005
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Seattle
Dec 13, 2005
#23
  • Dec 13, 2005
  • #23
dirty :taco: said:
I just unplugged the sensor and the light went off. That new cap and sensor was more like $60 somethin. So im gonna do a readiator flush, put all new hoses on it, new thermostat and radiator cap and hope that it is good to go (the previous owner never did that stuff and he had it 2 years). Then Ill just keep an eye on it to see if its leakin coolant or what

As far as the IAC spacer thing I ordered it 2day and they said it should be in tommorrow, so Ill try to pick it up after I change the tranny mount
Click to expand...

All I am saying is that most of the time the sensor is still functional, but the build up of debri on the metal prongs prevents the sensor from sending out the correct signals. 5 minutes in cleaning with a mild solvent may fix the check engine light.
 
D

dirty slut

New Member
Nov 12, 2005
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Dec 14, 2005
#24
  • Dec 14, 2005
  • #24
Update:

I installed the spacer and it is still doing it. It is hard to tell which way the spacer is supposed to go but Im 99% sure I did it right. I also had to screw in the 2 idle adjust screws all the way in in order to get it to Idle under 1K, it use to idle at 750, now the lowest it goes is about 900. The directions it comes with also says to back the throttle plate screw out so it dosent touch the plate anymore, I did that and now the gas pedal kind of sticks. Is that screw supposed to rest against the back of the throttle plate, to prevent it from coming all the way back? Mine is not touching it right now.

Im going to continue to try the rest of the things and see if it fix's it. Hopefully I can do the PVC today, if not, Ill do it tommorrow.
 

RUNINAGT

Member
Oct 3, 2005
237
2
18
CHARLESTON S.C.
Dec 14, 2005
#25
  • Dec 14, 2005
  • #25
WOW.amnit: crapola From what I can remember mine went on and smoothed out completely right after. We did have to adjust some, but not a lot. I dont remember anything about the idle screw. One of my Techs installed it, but I was right next to him. Seemed to go on pretty quick. umm I dont know . I guess the frustration continues. I went through a bunch of things before the spacer including the fuel pump. It's been awhile since mine was done and I no longer have the Stang. Sorry dude I was try'n to help. I would check to make sure that thing is adjusted correctly. Maybe ask one of the techs @ Ford.
Keep me up to date.
 

vristang

15 Year Member
Mar 31, 2005
4,933
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Seattle
Dec 14, 2005
#26
  • Dec 14, 2005
  • #26
dirty :taco: said:
Update:

I installed the spacer and it is still doing it. It is hard to tell which way the spacer is supposed to go but Im 99% sure I did it right. I also had to screw in the 2 idle adjust screws all the way in in order to get it to Idle under 1K, it use to idle at 750, now the lowest it goes is about 900. The directions it comes with also says to back the throttle plate screw out so it dosent touch the plate anymore, I did that and now the gas pedal kind of sticks. Is that screw supposed to rest against the back of the throttle plate, to prevent it from coming all the way back? Mine is not touching it right now.

Im going to continue to try the rest of the things and see if it fix's it. Hopefully I can do the PVC today, if not, Ill do it tommorrow.
Click to expand...

If you cannot adjust your idle down lower than 900 with the set screw, then I would supect a vac leak. At least that is what my fix was when I could not get the idle to drop.

good luck
 
D

dirty slut

New Member
Nov 12, 2005
59
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0
Dec 14, 2005
#27
  • Dec 14, 2005
  • #27
Yeah, that is next on the list after I do this complete radiator flush.

Those vac lines are alittle overwhelming b/c they are all over the place and all different sizes.
 

RUNINAGT

Member
Oct 3, 2005
237
2
18
CHARLESTON S.C.
Dec 14, 2005
#28
  • Dec 14, 2005
  • #28
You know another thing you can do is find a shop that has a smoke machine to check for a vacuum leak. We have one @ our shop. It dont take long to use it. Minumal charge also. We charge a 1/2 hour ($40.00) to hook up to it. Its good for finding leaks the eye can't find
 

vristang

15 Year Member
Mar 31, 2005
4,933
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Seattle
Dec 14, 2005
#29
  • Dec 14, 2005
  • #29
RUNINAGT said:
You know another thing you can do is find a shop that has a smoke machine to check for a vacuum leak. We have one @ our shop. It dont take long to use it. Minumal charge also. We charge a 1/2 hour ($40.00) to hook up to it. Its good for finding leaks the eye can't find
Click to expand...

I haven't heard of this process before. Can you describe it a little more?

jason
 

RUNINAGT

Member
Oct 3, 2005
237
2
18
CHARLESTON S.C.
Dec 15, 2005
#30
  • Dec 15, 2005
  • #30
Yep, it's a machine that hooks to the main vacuum harness. Simply turn the machine on press a hand held button and it sends smoke thru the vacuum system. wait untill you see smoke coming from an area. Works real well on stubborn hard to find leaks. It can show a leaking intake, cracked vac line ect.. We use ours a quite often. I would call around to see if someone in your area has one of those machines. If you were local to me I'de say come on buy our shop and show ya.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Dec 15, 2005
#31
  • Dec 15, 2005
  • #31
RUNINAGT said:
Yep, it's a machine that hooks to the main vacuum harness. Simply turn the machine on press a hand held button and it sends smoke thru the vacuum system. wait untill you see smoke coming from an area. Works real well on stubborn hard to find leaks. It can show a leaking intake, cracked vac line ect.. We use ours a quite often. I would call around to see if someone in your area has one of those machines. If you were local to me I'de say come on buy our shop and show ya.
Click to expand...

Sounds like a good way to locate vac problems. I will have to keep this in mind for the future. If only I could trust one of the local shops with my car.

Thank you.
 
D

dirty slut

New Member
Nov 12, 2005
59
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Jan 21, 2006
#32
  • Jan 21, 2006
  • #32
Update:

So far (knock on wood), I have not had any more surging since I replaced that spacer. I did at first once or twice, maybe everything trying to get adjusted, ECU or whatnot, I dont know, but it hasnt surged since then. I also did the cooling system flush and PCV/groumet/ and screen change around the same time, I dont know if that had anything to do w/ it but so far so good. I am also going to get to the vac hoses when I get a chance.

Just didnt want to discourage anyone having surging problems from going out and getting that spacer!!
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
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37
Jersey Shore
Jan 21, 2006
#33
  • Jan 21, 2006
  • #33
Niice so that spacer did fix it?
 
D

dirty slut

New Member
Nov 12, 2005
59
0
0
Jan 21, 2006
#34
  • Jan 21, 2006
  • #34
87stangdiddle said:
Niice so that spacer did fix it?
Click to expand...

seems that way, if it wasnt a 100% fix it was atleast a 95% fix and I recomend it
 

Black1987Stang

Active Member
Aug 22, 2004
1,422
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Jersey Shore
Jan 21, 2006
#35
  • Jan 21, 2006
  • #35
Cool
 
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