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Topic: 1987 Thunderbird Turbo Coupe Idle issue help (Read 6858 times) previous topic - next topic

1987 Thunderbird Turbo Coupe Idle issue help

I have a few foxbody mustangs and this is my first turbo coupe so any help would be greatly appreciated.

I am having issues with my 1987 Turbo Coupe, I can not get the car to idle properly.

things I have done to try to fix.
REPLACED AND ADJUSTED TPS
REPLACED IAC WITH ONE FROM A N/A 4CYL THAT RAN PERFECT
REPLACED ICM
REPLACED CAP AND ROTOR

I am not sure where else to start I was reading that I can not use a IAC from a n/a car but the car was doing this same issue before I did all this work. I checked for vacuum leaks but have found nothing out of the ordinary.

I have a video of the car and what it does.

Note I am not touching the gas at all on the car it is doing this all on its own. Sometimes the car will even get stuck around 2-2500 rpm but if you shut if out and restart it will stop and run fine for a few minutes.

Video
https://www.dropbox.com/s/8cqq5r5e2t...issue.mov?dl=0

1987 Thunderbird Turbo Coupe Idle issue help

Reply #1
Video won't play for me, on my phone.

Have you tried running codes?
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com


 

1987 Thunderbird Turbo Coupe Idle issue help

Reply #3
So what's a ICM??

If you mean the TFI ign module on dist, those will cause all sorts of issues but if it's causing a idle problem it's a 99% it'll be bucking and jumping when you are driving it...

Probably 95% of the time a high hanging idle is bad or misadjusted TPS, set it below the .999v everyone thinks these cars need... No more than .9 and probably .85v is better...

1987 Thunderbird Turbo Coupe Idle issue help

Reply #4
Yup ICM is the ignition control module, generic term but indeed the TFI
I have to agree with the Tps and setting the base idle, checking the timing wouldn't hurt either 10 deg is what your looking for
1987 T-Bird TC: 5-Spd, 5-lug conv., CHE Rear CAs, '04 Cobra wheels and 13" Brakes, Vac Assist conv: '93 Cobra BB/MC & Wilwood PV, Gutted/Knived Intakes, T3 turbo, RFE6 Mani, Stinger 3" Exhaust & Oil Feed, 255HP Walbro, Kirban AFPR, RR Cam, Esslinger Cam gear and Round Tooth Conv., Gillis Boost Valve, Speedway Dual Valve Spring,  K&N, 130a 3g Alt conv., 140mph Speedo
Running Better Than Ever :burnout:

1987 Thunderbird Turbo Coupe Idle issue help

Reply #5
Quote from: Ramos617;447700
Yup ICM is the ignition control module, generic term but indeed the TFI
I have to agree with the Tps and setting the base idle, checking the timing wouldn't hurt either 10 deg is what your looking for


I am going to recheck a few things this weekend and recheck with my code reader and let you guys know if I find any new codes.

Thanks so far for the help.

1987 Thunderbird Turbo Coupe Idle issue help

Reply #6
Ok I was able to read the codes again and I got the following:

During the KOEO test I got the following codes in the following order 23, 83, 23, 83, 10, 72

23
-Throttle Position Sensor Out Of Self Test Range
C/O/R

83
-Integrated Relay Control Module (2.3L Turbo & 2.5L)
O
-EVP/EGRC/EGRV (2.3L OHC & 3.8L CFI)
O
[COLOR="#B22222"]I am guessing the EGR again but I don't know about the first part of the code with the relay[/COLOR]

72
-Insufficient Manifold Absolute Pressure/Mass Air Flow Change During Dynamic Response Test
R
-Power Interrupt Software Re-Initalization Detected (1.9L & 2.3L Turbo)
C
[COLOR="#B22222"]I am assuming this means a vacuum leak. Any info on this code wold help.[/COLOR]

Then during the KOER test I got the following codes in the following order 23, 25, 23. 25

23
-Throttle Position Sensor Out Of Self Test Range
C/O/R
[COLOR="#B22222"]Looks like I will try to adjust the TPS sensor to fix this. Or any other suggestions you guys have for this code.[/COLOR]

25
-Knock Not Sensed During Dynamic Response Test
R
[COLOR="#B22222"]I don't know why I got this code? Hopefully this is just a simple replacing the knock sensor.[/COLOR]

If anyone has had any issues with these code let me know what you did to fix them or any ideas to fix them.

Thanks.

1987 Thunderbird Turbo Coupe Idle issue help

Reply #7
http://turbotbird.com/techinfo/Idle-TPSadjustment_Revised_June2005.html

^This should fix your high idling but because of the other codes I would make sure all your vacuum lines are hooked up and good

http://turbotbird.com/faqs/Vac_Diagram.htm
^Here's a vacuum line diagram for these cars

The knock sensor might just be unplugged since a lot of people do that to eliminate the ecm from pulling any timing from false signals
 it's on the lower intake facing the fire wall
1987 T-Bird TC: 5-Spd, 5-lug conv., CHE Rear CAs, '04 Cobra wheels and 13" Brakes, Vac Assist conv: '93 Cobra BB/MC & Wilwood PV, Gutted/Knived Intakes, T3 turbo, RFE6 Mani, Stinger 3" Exhaust & Oil Feed, 255HP Walbro, Kirban AFPR, RR Cam, Esslinger Cam gear and Round Tooth Conv., Gillis Boost Valve, Speedway Dual Valve Spring,  K&N, 130a 3g Alt conv., 140mph Speedo
Running Better Than Ever :burnout:

1987 Thunderbird Turbo Coupe Idle issue help

Reply #8
Fix first code given as it's the horse turd in a sea of fly specks... Then recheck, likely at least part of the other codes will have disappeared...

1987 Thunderbird Turbo Coupe Idle issue help

Reply #9
Egr code won't effect driveablility, unless its caused by a broken vacuum line.

Replace/adjust the tps, do a base idle reset. If it won't idle low enough, then either your iac is gummed up or bad, or you have a vacuum leak. A low manifold pressure also points to a leak.

The plastic vacuum distribution blocks like to crack and break, especially if you have bad motor mounts. It will pull the hose off or break something when the motor moves.

My bet would be both a bad tps and a big vacuum leak.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

1987 Thunderbird Turbo Coupe Idle issue help

Reply #10
Quote from: speedracer89;447876
Ok I was able to read the codes again and I got the following:

During the KOEO test I got the following codes in the following order 23, 83, 23, 83, 10, 72
23 & 83 are "O" codes
23 check voltage on TPS green wire for 0.6 to 0.9 volts.
83 IRCM problem. With engine running, turn the A/C on, both fans should run.
10 is the divider between "O" and "C" codes. 72 is a "C" code
72 The EEC detected a power interruption and reinitialized its self.

Quote
Then during the KOER test I got the following codes in the following order 23, 25, 23. 25
These are "R" codes
23 TPS adjustment again.
25 during the KOER you should get a "10" code. This is when your "dynamic response" should be to momentarily goose it to WOT to make it ping for the knock sensor to detect. (wouldn't worry about this one)

The other code definitions you listed are not for your car.

Check the negative battery cable. You should have one heavy gauge wire to the engine block and a smaller (pigtail) wire the chassis.
The chassis ground should have two other wires on that same grounding point. They are the EEC and IRCM ground wires.

The "C" (continuous memory) codes are stored while you are driving. Run KOEO and disconnect the code reader while the codes are displaying. This should reset the 72 code. Rerun KOEO to check that it worked.
Drive the car to see if it stores another 72 code.

1987 Thunderbird Turbo Coupe Idle issue help

Reply #11
Wow thanks for all the tips so far I am going to try this stuff Wednesday that is my next free day to work on the car.

1987 Thunderbird Turbo Coupe Idle issue help

Reply #12
Quote from: Ramos617;447878
http://turbotbird.com/techinfo/Idle-TPSadjustment_Revised_June2005.html

^This should fix your high idling but because of the other codes I would make sure all your vacuum lines are hooked up and good

http://turbotbird.com/faqs/Vac_Diagram.htm
^Here's a vacuum line diagram for these cars

The knock sensor might just be unplugged since a lot of people do that to eliminate the ecm from pulling any timing from false signals
 it's on the lower intake facing the fire wall


Do you know if it matters if I use a TPS from a n/a 4cyl car or even a V8. I have a few extra when I did some 5.0 swap in my fox stangs.

1987 Thunderbird Turbo Coupe Idle issue help

Reply #13
Quote from: speedracer89;447980
Do you know if it matters if I use a TPS from a n/a 4cyl car or even a V8. I have a few extra when I did some 5.0 swap in my fox stangs.

The EFI 4cyl should be same, the 5.0 defiantly not as they are physically different in their mounting(one mounting hole is offset on the 4cyl)...

1987 Thunderbird Turbo Coupe Idle issue help

Reply #14
Ok so I have been messing around with the car here and there I reset the idle and Tps as mentioned above and the car started running better, but the problem I was having is the idle would drop off every so often almost to a stall, well one lucky day and it did stall I found out I wasn't get spark so I pulled the distributor and found the gear was stripped and the auxiliary gear in the motor was cracked. So no I'm looking for a auxiliary shaft.

Does anyone know where I can find one?

It this part number.

auxiliary shafts ( fuel pump cam )   E4ZE-6K230-AA