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Discussion Starter #1
My son has an 89 bronco which the motor went. I bought an 91 truck for the motor and other parts.I swaped the motor from the 91 leaving the harness ( motor side ) attatched. When I started the truck it ran ok but some of the guages werent working, so I swaped the old harness started it up and everythin was fine untill I took it for a ride and the trans isnt shifting. I called someone in a trans shop and he said thetrand was no good.I replaced the trans (out of an 89) and it's still doing the same thing.Then someone said th pcm was bad so I replaced that and it's still doing the same thing. Someone now is saying something about the wires going to th 5 prong connector on the trans. THANKS FOR ANY HELP!!!:banghead
 

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Check Codes
See How To Run A Self Test or purchase a OBD-I Code Reader, such as the Equus 3145 OBD-I Code Reader. Then, refer to the list of ODB-I Codes to point you in the general direction.

Check Vehicle Speed Sensor (VSS)
The VSS is critical to the electronic E4OD. It sends an AC Frequency Wave to both the Cruise Control Module, and more importantly to the PCM indicating vehicle speed. In relation to the E4OD, this signal allows the PCM to determine shift points. Additionally the VSS Signal provides input to the Anti-Lock Braking System (ABS) on 1992 and newer Broncos.

1990-1991 Broncos have mechanical speedometers connected to the Transfer Case Tailhousing by cable and gears. The VSS is part of this system and sends a usable AC Frequency separately to the Cruise Control and PCM which controls both engine and E4OD functions. It is important to note that electrical schematics show one VSS wire going to PCM Pin #3 (VSS+) and the other wire going to PCM Pin #6 (VSS-) and to Chassis Ground. Also note that there is a separate ABS Sensor on the Rear Differential solely for RABS Module Input, which also measures vehicle speed.

1992 and later Broncos upgraded to an electronic speedometer connected to a Programmable Speedometer/Odometer Module (PSOM). The speedometer cable and VSS were removed from the transfer case and the ABS Sensor on the rear differential became both the VSS and ABS Sensor. The signal goes through the ABS Module to the PSOM, for speedometer/odometer functions, and is then sent to the Cruise Control and PCM. It is important to note that electrical schematics show one VSS wire going to PCM Pin #3 (VSS+) and the other wire going to PCM Pin #6 (VSS-) with No Chassis Ground.

Check the Manual Lever Position Sensor (MLPS)
Test and adjust the MLPS as necessary.

Check the E4OD Solenoid Pack
Transmission not shifting
help removing e4od solenoid pack


See these links:

E4OD Diagnosis Thread

Bronco Links - E4OD
 

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Since you probably have a C6 in the 89, Check the Vacuum line going to the trans. I had the same problem (It wouldn't shift), and it turned out to be a leaky vacuum line to the trans.
 

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Any more information on the truck? Engine? Trans? was it shifting fine before the engine went? sounds like something was left unplugged or not hooked up.
 

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Discussion Starter #9
Since you probably have a C6 in the 89, Check the Vacuum line going to the trans. I had the same problem (It wouldn't shift), and it turned out to be a leaky vacuum line to the trans.
Thanks but there is no vac. lines going to the trans
 

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I think more specific information is required (about the engine(s) and transmission(s)) to give a more accurate guess.
Sounds like you are trying to mix pcms and transmissions.

You changed a transmission based on a phone call to a transmission shop??

The 5 pin connector is the NSS and the reverse lights....doubt it's the problem.
 

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Thanks but there is no vac. lines going to the trans
Maybe thats your problem? Wouldnt an AOD also have vacuum lines?
If its a c6 like someone stated, than there are vacuum lines. It is on the firewall on the passengers side.

Also, has anyone ever put a stock AOD behind a 351? I reallly want an overdrive and my uncle has one laying around. Sorry bout the hijack

-Vance
 

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Maybe thats your problem? Wouldnt an AOD also have vacuum lines?
If its a c6 like someone stated, than there are vacuum lines. It is on the firewall on the passengers side.

Also, has anyone ever put a stock AOD behind a 351? I reallly want an overdrive and my uncle has one laying around. Sorry bout the hijack

-Vance
Nope the AOD is controlled by a cable that feeds the valve on the side of the tranny to control fluid pressure, IIRC, (been a while since I really messed with one. It will run from the throttle body down to the tranny adjusting it is farely easy.

I think someone put and AOD behind the 351 but I also think they had to use an e40d flywheel though. Use the search and it should come up I am having internet problem that and I am just ****ing lazy to search.
 

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Discussion Starter #13
THE MOTOR THAT I PUT IN THE 89 IS A 5.0 AND THE TRANS IS AN AOD. I TRIED ADJUSTING THE CABLE AND IT DIDNT MAKE ANY DIFFERENCE.
 

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penis
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THE MOTOR THAT I PUT IN THE 89 IS A 5.0 AND THE TRANS IS AN AOD. I TRIED ADJUSTING THE CABLE AND IT DIDNT MAKE ANY DIFFERENCE.
WOOOOOOOOOOo buddy no need to yell most of us here can read. have you tried to pull codes yet?

O.K. so the 89 was a 5.0 originally correct you installed a 91 5.0 I am assuming please correct if I am wrong.

O.K. 1989 had 2 types of trannies both noncomputer c-6 3 speed auto (used with the 351), and a AOD 4 speed (used with the 302). I suspect here lies your issue, you already swapped the tranny and ECU from the 91 correct? you will need to swap the steering column as well for the OD cancelation switch as it will send a signal to the ECU. One other thing is you current speedo working?
 

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Discussion Starter #15
WOOOOOOOOOOo buddy no need to yell most of us here can read. have you tried to pull codes yet?

O.K. so the 89 was a 5.0 originally correct you installed a 91 5.0 I am assuming please correct if I am wrong.

O.K. 1989 had 2 types of trannies both noncomputer c-6 3 speed auto (used with the 351), and a AOD 4 speed (used with the 302). I suspect here lies your issue, you already swapped the tranny and ECU from the 91 correct? you will need to swap the steering column as well for the OD cancelation switch as it will send a signal to the ECU. One other thing is you current speedo working?
Sorry I wasnt yelling. the only thing I swaped from the 91 was the motor (5.0). The trans (AOD)was the original one.
 

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Discussion Starter #17
Yes the orignal motor was a 5.0. At first I used the harness from the 91 which didnt work correctly,so then I switched to the original harness back .
 
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