Engine computer and harness issue

[Jeffreyfordaholic]

I just pulled engine and automatic transmission out of a 91 Lx to put in a 90 Gt but going with a T5 transmission.I used the engine harness from the Lx.I did a Trickflow top end kit.When I went to start the engine it was running black smoke rich.So after double checking everything with no success,I decided to swap the computer, The car fired right up and no black smoke.So im running a ANP computer in a 5 speed car. My question is will i have any issues and why didnt the A9L computer work with the engine swap ????

 

[90sickfox]

It comes down to the o2 sensor wire plug at the passenger side front bottom of engine. The auto and 5 speed use a different jumper configuration in that harness connector. If the wrong computer is used with the wrong jumper wiring it will damage the computer.

 

[Mustang5L5]

Really need to check to see if you burned out the trace on pin 46 in the ECU. a9L with an auto-pinned O2 harness is a recipe for frying ECU's. it causes voltage on pin 46 that shouldn't be there.

If you want to complete the 5-spd conversion properly, you will need to swap the trans harness to one with the NGS wiring, and repin the O2 harness to move the jumper to the correct location for your year harness. Then you can swap the A9L in.

Running the AOD ecu is fine and it works, but you sometimes get quirks like a hanging idle when you are in nuetral with the clutch out.

 

[Jeffreyfordaholic]

I think I may have fried the A9L computer from the jump by having the 02 harness connected.since I dont need catalytic converters,could i just disconnect the 02 sensors since in doing a hot rod type project ?

 

[General karthief]

Not if you plan to use the computer.

 

[Mustang5L5]

You need the O2 sensors with an ECU. It tells the computer if you are lean/rich and adjust injector pulse width accordingly.

 

[Jeffreyfordaholic]

Ok Thanks for the information. This is my first computerized/ fuel injected project. I've always did the old school carburetor set ups. !!!!

 

[Jeffreyfordaholic]

Whistling noise at idle coming from the BBK and TrickFlow top end set Up. Guy at summit says its the amount of air going thru the cold air intake thats causing the whistling noise.

 

[General karthief]

Ahhhh, the 'ol whistling dixie' throttle body.
Really, it could be a vacuum leak, anyway I can just about guarantee it ain't the cai.
my bbk throttle body whistles, chased that rabbit for over a year.

 

[Jeffreyfordaholic]

DID YOU FIND OUT WHY IT HAD THE WHISTLING SOUND AT IDLE ?

 

[General karthief]

Jeez, stop yell'n, I'm old not def, I do have a touch of tinnitus but that is another story.
The throttle body is the cause, for what reason? Airflow does funny sht as it is pulled through and past stuff. Some have worked the sharp edges at the egr opening in the plate with mixed results. I just live with it for now.
I used to get strange looks at the fuel pump by a couple ricers in the neighborhood, I used to tell them my BOV was noisy.

 

[Blown88GT]

I get looks while waiting for a traffic light. The straight cut gears of the supercharger. One guy asked if I had a chip & I said "no chip".

 

[Mstng93SSP]

I personally have never seen a BBK throttle body that doesn't whistle. I took mine off and replaced it with an accufab. Whistle gone.

 

[Blown88GT]

Mine doesn't whistle.

 

[Mstng93SSP]

Mine doesn't whistle.

You are lucky.....

 

[Sparky714]

DID YOU FIND OUT WHY IT HAD THE WHISTLING SOUND AT IDLE ?

I had one that whistled. Took it off, rounded the sharp edges on the holes for the IAC with a dremel, and no more whistle.