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Need A Little Help

  • Thread starter Thread starter Chris W
  • Start date Start date Jul 24, 2017
C

Chris W

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Jul 24, 2017
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#1
  • Jul 24, 2017
  • #1
I have an 87 mustang gt, I recently put a 94 engine in I had to swap the distributor, it will run at tdc but it won't idle.. is there a crank or cam sensor in the motor I'm overlooking should it still run if there not hooked up? Should the throttle position sensor be recalibrated? Car is speed density, motor odviously mass air.. ANY help would be GREATLY appreciated. .thanks
 

Davedacarpainter

Chicks can make things hard if they’re inspired...
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Jul 24, 2017
#2
  • Jul 24, 2017
  • #2
Hey. Chris, welcome to Stangnet.

I'm going to move your thread over to our fox tech subforum. Someone will help you there.

Good to have you with us.
 
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imp

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Jul 13, 2017
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#3
  • Jul 24, 2017
  • #3
Chris W said:
I have an 87 mustang gt, I recently put a 94 engine in I had to swap the distributor, it will run at tdc but it won't idle.. is there a crank or cam sensor in the motor I'm overlooking should it still run if there not hooked up? Should the throttle position sensor be recalibrated? Car is speed density, motor odviously mass air.. ANY help would be GREATLY appreciated. .thanks
Click to expand...
@Chris W
The '87 wiring, and all other supporting sensors and such were retained? Only thing different is the '94 engine? Did you keep the '94 Upper Intake Manifold, or use the '87? Considerable difference there. '94 also had a different Throttle Body, Throttle Position Sensor, and Idle Air Control valve.

'94 engine doesn't care about Speed Density or Mass Air; given S.D. computer, it should run OK. Distributor from '87 was used in '94, because of TFI Sensor mounted on Distributor, instead of '94 remote-mount? Make certain you have the Distributor properly inserted in the engine. There is NO crank or cam sensor used with the '94, crank position and spark all come from the TFI. Set your distributor to 10 degrees BTDC WITH THE SPOUT CONNECTOR in the harness REMOVED. Then, put it back.

Your best bet to avoid the questions posed by the '94 T.B. and it's hardware is to use your '87 Upper Intake, with it's T.B., T.P.S., and IAC. Inlet ductwork fits better, too. Beyond that, I can't help much more. Others with more smarts than me, will hopefully jump in. Good Luck. imp
 

jrichker

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You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. It includes how to dump the computer codes quickly and simply as one of the first steps. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 250,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
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Chris W

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Thanks for the replies, I think my problem is I'm using the 94 intake.. will have to find an 87 and try it
 

General karthief

wonder how much it would cost to ship you a pair
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#6
  • Jul 24, 2017
  • #6
Any upper intake for a 87 thru 93 V8 mustang will work, I think the 86 is the same too.
 

imp

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  • Jul 24, 2017
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Chris W said:
Thanks for the replies, I think my problem is I'm using the 94 intake.. will have to find an 87 and try it
Click to expand...
@Chris W
I thought by the way you wrote, you had the entire '87 engine to begin with. imp
 

General karthief

wonder how much it would cost to ship you a pair
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Make sure you use the sensors for the 87.
And you did connect all the ground wires back, there are four of them in the engine compartment. They are very important to the efi operations.
 
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mikestang63

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#9
  • Jul 24, 2017
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i assume you did not install the mass air meter from the 94
it doesnt matterer if you used the 94 intake as long as you installed the IAT sensor in the airbox and used your 87 distributor, pulleys, accessories, brackets, exhaust
Yes you need to adjust the TPS and base idle

Not sure why you didnt just use the 94 EEC and swap over the 87 to mass air. Its only 4 wires to repin and the MAF wiring. You can buy the kit for less than $100 or make one yourself using a JY MAF pigtail
 
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jrichker

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mikestang63 said:
i assume you did not install the mass air meter from the 94
it doesnt matterer if you used the 94 intake as long as you installed the IAT sensor in the airbox and used your 87 distributor, pulleys, accessories, brackets, exhaust
Yes you need to adjust the TPS and base idle

Not sure why you didnt just use the 94 EEC and swap over the 87 to mass air. Its only 4 wires to repin and the MAF wiring. You can buy the kit for less than $100 or make one yourself using a JY MAF pigtail
Click to expand...
The 94-95 T4M0 computer has a different pinout from the A9 series computers used in 89-93 Mustangs. It can be made to work, but there is much to be done to make it work. You must move pins around in the computer wiring harness connector and some other changes to accommodate the CCRM modules that aren't present.
 
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