Hanging idle and feels low on power

GEORGEKLASS

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Need you help guys, I'm really starting to get annoyed with my GT. Here's what I'm dealing with.

For the past month, the revs go up 3-400 RPM between shifts and or/ kinda hang in between shifts. Another issue I had since I bought it was more often than not the car would start and stall unless I gently held the throttle down for about 30 seconds. This would happen 95% of the time when the car was hot and then sat for 10-15 minutes. It's done it to me a few times on cold start.

I figured it was the IAC valve at this point. So I bought a new Motorcraft piece and installed it along with a nice Ford Motorsport 65mm throttle body I scored. Besides a nice noise when I give gas, symptoms have not gone away. :undecided: If I unplug the TPS or the IAC the revs drop as soon as I push down the clutch.

I went for a rip yesterday and she feels down on power as well.

Here is a list of all the parts I have changed on this car. Everything is Motorcraft unless stated

- Spark plug wires
- Spark plugs (NGK)
- Cap and rotor (MSD)
- Coil
- ECT
- ACT (Standard)
- 02 sensors
- Fuel Filter
- IAC valve

I swapped the MAF with a spare I had lying around, didn't notice any difference either.
 

CC'S95GT

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do a voltage or resistance ck on the TPS.
Move the throttle very slowly through the range and look for a drop in voltage or ohms (depends on what the meter is set on).
 
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GEORGEKLASS

GEORGEKLASS

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do a voltage or resistance ck on the TPS.
Move the throttle very slowly through the range and look for a drop in voltage or ohms (depends on what the meter is set on).

I had checked the TPS when it was on the stock throttle body checked out OK. I'll be honest I slapped it on the FMS unit without checking voltage. I will check it out tomorrow. I do have a question out the ECT tho.


The Motorcraft unit I bought came with a new plug. Changing it was no problem except for the fact the new plug had 2 white wires! I wasn't sure which one went where. I installed it quick fast by just twisting the wires and wrapping in electrical tape. Didn't want to do anything permanent yet. DOes it matter which ones goes where and if so, how do I know which way is right. Sighhh
 

CC'S95GT

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I had checked the TPS when it was on the stock throttle body checked out OK. I'll be honest I slapped it on the FMS unit without checking voltage. I will check it out tomorrow. I do have a question out the ECT tho.


The Motorcraft unit I bought came with a new plug. Changing it was no problem except for the fact the new plug had 2 white wires! I wasn't sure which one went where. I installed it quick fast by just twisting the wires and wrapping in electrical tape. Didn't want to do anything permanent yet. DOes it matter which ones goes where and if so, how do I know which way is right. Sighhh

I have no idea about the ECT. I'm still running the origional
 
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GEORGEKLASS

GEORGEKLASS

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TPS was at .93 and 4.6 at full throttle. Seemed to be getting higher consistently until WOT.
 

ttocs

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have you adjusted the screw on the top of the TB that adjusts the idle? Try turning if a few notches in/down to reduce air and it should fix the hanging idle.

As for the reduced power I though the stock tb was 65mm so is the new one any different from the old one?
 
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GEORGEKLASS

GEORGEKLASS

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have you adjusted the screw on the top of the TB that adjusts the idle? Try turning if a few notches in/down to reduce air and it should fix the hanging idle.

As for the reduced power I though the stock tb was 65mm so is the new one any different from the old one?


I did a base idle reset this morning. I just played with the screw, did absolutely nothing. I'm going to let it cool down and install the stock throttle body again with the new IAC valve and see if there is any difference. The stock throttle body is 60mm on 94-95 GT and Cobra.

Today after sitting for 15 minutes it just wouldn't want to idle when I restarted it. Surge and die unless I held the throttle. Finally after a minute I just took off and it seemed to stabilize.

I'm really starting to lose my shit with this car. I just don't understand what I'm doing wrong.


***EDIT*** Just went and turned the screw all the way down. Went for a ride and idle has improved considerably!!! Lets see how she does on start up!
 

ttocs

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you will not notice much difference in the idle on the screw till its nearly wide open and when it is that is when I noticed it changed during shifting.
 
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GEORGEKLASS

GEORGEKLASS

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you will not notice much difference in the idle on the screw till its nearly wide open and when it is that is when I noticed it changed during shifting.

I just pulled over and turned it pretty much to the top. Idle was hanging really bad.

With it fully closed the hanging was almost gone but the car would not restart without stalling. I turned it until it would start and not stall. Still have a little surge tho.
 

toyman

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On average the TB screw will be about 1.5 - 2 turns backed off from being seated. Don't play with the idle stop screw on the linkage.
 

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