[GT306]

i got codes
22-map
31-evp
41-o2 lean
51-ect
53-tps
54-act
(1993 gt, stock heads/cam. cobra intake, full exhaust)
still seems to have good power


car started acting wierd today after i got off work....i got in and started it up and it was idling just fine then once i pressed teh clutch in the car went haywire. the rpms were all over the place started surging like crazy, when i drove it, it would buck really bad when i let off the gas, seemed to do it more at a higher rpm . also my o2 sensors arent hooked up right now , just had some exhaust work done and need the extensions which should be here shortly but they have been disconnected for about a week now and its been running just fine until now. after reading some threads i ended up opening up my computer and the pictures show what i found.

 

[need4spd90]

Toast:bigthumbsup

 

[Smurf stang]

In my professional opinion....I think it's fried.

 

[GT306]

so is it ok to replace with an auto parts store reman ecu?

 

[need4spd90]

yes..BUT...

something probably caused this to happen..be wary of slamming in your brand new computer and frying it again...

if you look at a EEC-IV pinout, you'll notice all those sensors that are throwing codes above share a common ground wire at pin 46...now, a burned trace on pin 46 does not look like what you posted(been there done that), and also, burning pin 46 usually does not allow codes to be pulled...

but you may want to check pin 46 for voltage
push the clutch down, with the computer still removed, hook up a DVOM to pin 46 on the EEC connector, then crank the engine using the key..look for any voltage coming in...

also check continuity/resistance for wires/circuits on pin 30, which is for the clutch pedal switch...something may have arced and shot 12v into that computer..

these are just suggestions, seemed awfully coincidental that the computer fried when you pushed the clutch in, after having recent work on your o2 sensors

having the wrong o2 sensor harness will fry the pin 46 trace, but this is usually in 4cyl-v8 swap cars and guys dont know there are different o2 sensor harnesses

 

[micmax]

there is always a cause when anything burns you have to find it BEFORE you put new parts in or they will burn too maybe your unplugged o2 sensor wires shorted maybe to the exhaust

 

[GT306]

ok thanks guys, looks like i got some work to do

 

[need4spd90]

This an original v8 5spd car?
Get those o2s hooked up...

 

[Hockeyman48]

Also you might want to check wire harness under the dash to see if any contact from clutch arm,pedal,etc.,has created a problem with wires shorting together with metal contact of clutch or shorting to ground.

 

[GT306]

the car is an original v8 automatic converted to 5 speed

 

[need4spd90]

Hmm..pin 30 gets its ground differently in aod cars vs. T5. The aod grounds it somehow thru the starter relay vs the clutch switch on a 5spd car. This may be something to look into.

Does your car have a properly working clutch pedal switch?
Or is it just jumpered out? The wiring for it will be there from the factory, but ford changed a few things between the auto and 5 spd cars.

Definitely check for voltage while cranking on pin 46 and 30 @ the EEC connector before installing the new computer

 

[GT306]

Hmm..pin 30 gets its ground differently in aod cars vs. T5. The aod grounds it somehow thru the starter relay vs the clutch switch on a 5spd car. This may be something to look into.

Does your car have a properly working clutch pedal switch?
Or is it just jumpered out? The wiring for it will be there from the factory, but ford changed a few things between the auto and 5 spd cars.

Definitely check for voltage while cranking on pin 46 and 30 @ the EEC connector before installing the new computer

no the clutch switch doesnt work, meaning i can start it without the clutch being pressed in. when i first got it , it had a wire running from the black connector to the grey connector below the steering wheel next to the fuse box, im guessing these connectors is where the clutch switch would have hooked up? if the wire fell out of either of the connectors it would not turn over.

im going to go check voltage in just a minute and i will let you know what happens

 

[need4spd90]

Check clutch in and out..any voltage is bad

 

[GT306]

Check clutch in and out..any voltage is bad

not sure what you mean?

 

[GT306]

i checked the voltage at pins 30 and 46, seemed to bounce all over the place with voltage on both pins when i cranked it.

 

[GT306]

ok so with clutch out i had voltage in both pins when i cranked it.
the voltage bounced between 2 volts to 8 volts up to 17.

 

[David.kinter]

As I posted in the other thread, what are you paying for the new ECU? I have an A9L laying around the house and I don't plan on using it. I'm sure I could beat the price of the auto store and save you some money.

 

[GT306]

As I posted in the other thread, what are you paying for the new ECU? I have an A9L laying around the house and I don't plan on using it. I'm sure I could beat the price of the auto store and save you some money.

well i had to pay to order it .. it was $110

 

[GT306]

no different with clutch in...... still has voltage when cranked in both pins

 

[need4spd90]

yep thatll do it....

Unplug the main oxygen sensor harness and try it again. The o2 maintain connector is under the hood, below the mass air sensor. Should be a kinda round looking 8 pin style plug, it'll have a little looped jumper on one side