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Discussion Starter #1 (Edited)
Back agian, :D

1. Disconnect the battery

2. Take apart the 10 pin connectors.

3. Get a small nail and slightly crimp the female side of the connectors, this will help tighten the connectons. Do this on the complete assembly.

4. Put dielectric grease on the male side of the connectors
and reassemble.

This is the fix for a stuck/high/surging idle. Example: You pull up in the driveway or to a stop light with the clutch in and the car idles it self up to 2K or 3K rpms and then stays there, then finaly drops down when it wants to. Or, your driving down the road, push the clutch in, and the car stays at whatever rpm you were at when you went to make the shift for more than a sec or two.

The 10 pin connectors are black and white plastic connectors that go between the main wiring harness and the fuel injector harness. They are located at the firewall end of the intake. I will try to find some pics and post them.

And you all thought this thread was dead.

Wes

EDIT:http://66.96.130.106/archives/2002/01/tenpin/
EDIT:Cleaning TB and IAB

EDIT(1/18/03) There is quite a debate about setting the tps at .98v or .97v or what ever, well. Set your voltage at .93v and enjoy. The info below is being posted because other than the voltage value given, it is pretty much dead on.

How To Adjust TPS
"Muscle Mustangs & Fast Fords"
April 1993
------------------------------

The throttle position sensor is one of those things that falls
into the category of "computer stuff" that makes a big difference
and is easy to deal with, but average people like us would never
know about. Without the proper adjustment, the throttle position
sensor (TPS) will give the computer a false reading as to the
exact throttle opening. A false reading will limit wide open
throttle performance (something we definitely don't want). A
voltage reading must be taken using a digital volt/ohmmeter
(DVOM) with the Key On/Engine Off and with the Key On/Engine
Running. A Radio Shack DVOM, part No. 22-185A, works well for
this job.

The TPS is located directly on top of the throttle body and is
adjusted by loosening the two phillips mounting screws and
swiveling the sensor until the highest reading is found. It may
be necessary to elongate the holes with a small file to achieve
the desired reading.

The spec range for Key On is from .88 to 1.0 volt; shoot for the
.97 to .99 volt. With the engine running, the voltage should be
no higher than 1.05 volts.

Incorrect Throttle Position Sensor (TPS) voltage will result in
reduced performance. The best way to take a TPS voltage reading
is by using two safety pins through the wires coming from the
sensor. The positive lead is attached to the green wire, while
the negative goes to the black wire. Always ground the meter
through the sensor's black wire. This gives a direct, and more
accurate ground into the computer.
 

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I agree! I tried everything else, then cleaned the 10 pins and what do you know, idles like a champ! Damn frustrating to track down, but now I know.

jason
 

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Discussion Starter #3
TTT for guys in the windsor forum.

If you have questions post them, and if you find another fix post it, and post any info you think could help others.

Wes
 

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I was looking for this thread! Did a search after the site went down but came up empty. If you can post a pic that would be great!! I looked but could not find the connector in question. Thanks:)
 

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10 pins are little black and white trashcan looking deals mounted on the back of the intake. They should be visible because they arem mounted on a bracket that fits underneath the 5.0 decorative plate on the intake. You may actually have 4 instead of 2 because there was a recall to lenghten the harness.

jason
 

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I squeezed all the female pins in all 4 of 90's connectors today. The idle problem I have been having is still there, but it did have a different benefit for me. I don't know if the benefit came from the tighter connection or from the 1/2 hour or so the battery was disconnected, but my low end power has improved noticably. The car will spin the G60 McCreary tires from a 20 mph roll now where it did not spin the tires before I bent the pins. The power seems better from a dead punch too.

Maybe someone can give me some advice on how to fix my idle problem. This summer when the engine was stock the tach read about 800 rpm at idle. The car had underdrives on the crank and waterpump before I bought it and the volt gauge does not go up until about 1000 rpm. Even with this the car would idle before at 800 rpm.

When I added the parts in the sig, the engine would not idle at all. The car died every time it came to a stop. After driving it with this no idle situation for 50 miles or so, the engine would idle with a surging idle. I ordered the idle bleed plate and installed this and reset the TPS to .98V at idle and followed the directions in the kit about setting the throttle stop. The car was idling much better by the time I installed the kit, and the surging was intermittent. I found I could drive the car with both the plates screws screwed all the way in like the plate was not there.

I read a post that lowering the TPS to .93V helped another Corraller so I did that. I also read on Windsor that I should disconnect the ISC and should set the throttle screw to achieve the desired idle. I did this and set the throttle stop to lower the rpm (I readjusted the TPS). I found that under 1000 rpm the idle would surge wildly so I unscrewed one of the idle plates screws to raise the rpm. I cannot adjust the idle to lower than 1100 or so or the engine will surge. The surging is especially bad when the system is just at battery voltage under 1000 rpm. The car idle at 1100 to 1300 rpm now, but I would like to get it lower if possible. When I release the throttle while braking for a stop sign the tach does not drop right away and when I come to the stop they drop to about 1500 and stay there for a second then drop down to 1200 or so.

The car idles well when it is started cold, but when the temp gauge starts to move before the thermostat opens, the car will surge. The surge goes away once the thermostat opens unless the lights are on and the battery voltage drops.

Any suggestions? Thanks. Tom
 

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I have a question about the white and black ten pin connectors, why is there an extension between them? On my harness there is a six or eight inch extension between the main harness and the injector harness on both the white and black connectors. My coupe is a conversion car with a '93 cobra upper and lower and I just took the extensions out as it was just more wires. I have not fired the car as of yet, read my other post "TPS nightmare", should I put them back in or is it okay to leave them out?

Darren
 

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Discussion Starter #8
Alright, here is the deal on the extension/jumper harrness that ford installed there through the service centers. The harness was to short and would cause the conectors to sepperate. Also, ford was trying to do what the fix at the top of this thread does by sending out the jumperharness so that the ends would fit tighter.

The connectors send the Injectors the signal to fire by conecting the injectors to the fuel injector harness which conects to the main wireing harness via the ten pin conectors and the jumper harness in most cars, and then runs to the computer via the main wiring harness.

Ford issued a TSB for the fix, and I think it only applied to 89-92 maybe the early 93 cars, but I am pretty sure that ford eliminated the problem by then. There are alot of cars out there runing around with out the jumper harrness in there and they are getting Check Engine Lights with a whole host of codes where the computer is trying to trouble shoot itself to diagnose the problem but it can't.

My car has the jumper conectors taken out and the extra harness wire that was in the jumper harness spliced directly in on the fire wall/main wirering harness end. This eleminated, what,....... forty conector ends that could cause trouble while still giving my car the extra harness lenght it needed.

Good luck,
Wes
 

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Exactly what Wangstang said. I removed the extra harness from mine because there was plenty of slack for the old ones.

jason
 

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Discussion Starter #10
I would still recomend that you figure out a way to keep the extra harrness that the jumpers introduced in their somehow. Notice that I said mine have been spliced in so that you keep the extra wiring there.

By the way, this fix is for 88-92 and some 93 cars with mass air. Just wanted to clairify.


Wes
 

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HELP

I have a similar problem but i'm not sure if it is the same thing. If I am driving down the road and put the clutch in to shift the rpm stay at the same level they were at. When I start it up the rpm go from around 1000 to around 2500 and then back down a few times even though i do nothing. And when I come to a stop the car will go from around 2500 to 1000 and below, and it sometimes dies; also when it idles around 1000 rpm it is really rough. Any ideas?

By the way I have a '95 GT w/ GT40 intake, edelbrock aluminum heads, a ford motorsport cam, and headers, exhaust etc.... if it makes any difference. I think the cam might be part of the problem. PLEASE HELP!
 

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HELP

I forgot that my check engine light flashes 3 times when i start it up if anyone knows what that means. Thanks.
 

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So this fix does not apply to my 87 with stock computer? I have been having this problem for years with my 87 GT, even when under warranty. The fix the dealer would make was to replace the TPS. I have since tried to clean the TPS with contact cleaner when it acts up with some luck. Also, water in the TPS causes the same problem. With 211,000 on the clock, it could just be time to replace the TPS.

TommyN - How many miles are on your car and have you ever changed your O2 sensors? If you only have the idle problem when the car is warm, it could be having a problem when the computer goes into closed loop mode (warmed up) and uses the readings from the O2 sensors. If they are feeding the computer bad info, the computer could be adjusting your A/F mixture improperly. O2 sensors can cure lots of problems.

It could also be your fuel injectors. I had a problem with my Vette because one injector was not firing correctly and would cause the computer to constantly adjust the A/F mixture up and down causing the engine to idle very poorly and surge.

Just my .02.
 

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Discussion Starter #14
macin95five0
Let me do some reasearch. I will get back to you, what mods do you have, list them all.

Have you tride a new MAP or IAB valve? What about your TPS

schwaggs,

It should work on all EFI mustangs up to 92 or 93, but I havent had any personal experience with any car older than 88. Give it a try and post your results.

Wes
 

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Hey Wes, I have exactly the stuck/surging idle problems that you described. I crimped and packed the pins as you instructed but it made no apparent change. Lowering the idle TPS from .98V to .94V helped some. Any more ideas? The idle solenoid is clean. It's a '90 motor, rebuilt, balanced, GT40 heads, Cobra intake, 24lb injectors, 65mm TB. Thanx!:confused:
 

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quickbrick,

mine is similar to yours. a freind of mine adjusted the idle set screw on the TB and it fixed the idle problem. this was all after finally figuring out my TPS voltage problem was due to a bad EEC processor. my TB is a BBK and the set screw is on the bottom, a hex screw with a 3/8" jam nut. hope this helps.

darren
 

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Hi Darren. I can adjust the base idle up or down with that set screw, but I'm talking about the delay in rpms dropping back down to idle speed after the throttle is released - the revs stay up for a second or two instead of coming right down as they should.

When the IAB valve is unplugged, the idle drops as it should. Some guys at a local Ford speed shop (Racer Walsh) have the same problem but no answers.
 

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Ohhhhh, mine does the same thing. I fixed the irratic idle surge this way. When I start my car it will run at 1500 rpm and then idle at 1000 rpm. After I drive it and come to a stop sign and push the clutch in it will idle at 1200-1300 rpm and then in a few seconds it goes to 1000 rpm and stays. Once the car is at operating temperature this condition goes away.

The motor also idle hunts when I first start it for a few seconds and then settles in. I have a fairly high lift cam in it so I am hoping the EEC Tuner will alieviate that minor detail.
 

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Discussion Starter #19
Does the engine rev itself up, not just stay in the same spot when you push the clutch in but actualy increase the rpms, when you push the clutch in?

When you push the clutch in, does the engine hang at the RPM it was at for a few seconds and then drop?

Does the engine idle up when you come to a rolling stop and then take a second to drop all the way back down to where the idle is set?

The engine is actually supose to slowly drop rpms when the clutch is pushed while the car is at speed so that the engine rpm doesn't drop off causing excessive mismatch in the rpm of the engine and the rpm of the trany gears. If the engine doesn't do this, then it causes a major load to be dumped on the engine and the trany if the driver doesn't give the engine the extra gas to try and match the rpms of the two.

The engine idles up when your at a slow roll or rolling up to a stop sign and just stoped because the eec is supose to idle the engine up just incase the drive lets the clutch out with out giving the engine gas while still moving. This prevents a stall from occouring, or at least prolongs it.

Now, if your pushing in the clutch at speed and then holding it down for a 30-40 sec. and it's taking it that long to drop the rpms, then you might want to get a new IAB valve and see if that fixes your problem, just make sure you get a new gasket for it as well.
 

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Q: Does the engine idle up when you come to a rolling stop and then take a second to drop all the way back down to where the idle is set?

A: Yes.

So I can chalk it up to it is supposed to do that, cool. What about when I first fire it up and it does about five to ten seconds of idle hunt after it get off of "high idle"? I have a pretty healthy cam so I figure it is just compensating. Just for the record it is a Comp stick part# 35-308-8 or grind# FW 266H-R14.

Darren
 
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