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Engine electrical help

ok. I have done the 5.8L swap and have the car running. I am having issues with the A9L/mass air swap. I did the pin swap and tapped the other wires. My problem is over fueling at idle flooding the engine to not restart. I adjusted my timing to 12 degrees BTDC. When I did that I shut down the car, tightened the distributer clamp, then tryed to restart. It would not start. Waited an hour then it restarted. So i tryed to adjust the tps and I found that all 3 wire to the tps were at 5 volts. I dissconnected the tps and checked voltage at the harness side. Orange wire was 5v, green was 4.88V and black/white was 0.05v. So in other words the car is thinking it is at full throttle when starting.

Anyone have trouble with this?

I am also haveing a hunting idle too..

Oh and with the tps unplugged I went on a road test and the car went really nice. Lots of power. This the tps plugged in I bogg and lose alot of power.

Thanks guys
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #1
. I should mention that my tab/tad/evap solinoids are dissconnected.

I was looking at the cool cats site on the mass air swap and it says I have to swap some wires in the harness for the tab/tad solinoids. I don't remember if I have done that. I will have to check tomorrow. Says that I could also have a MAP to BP incompatabillity. This is a box of worms.

I hate electrical. LOL
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #2
Fix the TPS problem, otherwise it'll never run correctly... It must have around .9 to 1v on the green wire at idle or you're just ' in the wind...

BTW a WOT condition shuts off the injectors(activates dechoke mode), so I doubt you have a flooding problem...

Don't worry about the MAP/BAP, I've never seen a problem using one for the other...

Engine electrical help

Reply #3
Your black/white wire (Signal Return) is not getting where it needs to go.
With the TPS disconnected you should have 5v between the orange/white wire and the black/white wire.
The Sig Rtn wire also goes to the ECT, ACT, MAP and EGR position sensors.
Sig Rtn goes to pin 46 on the SO EEC. Is this one of your repinners?

Engine electrical help

Reply #4
I had a huge flood problem. You could smell it when I was cranking to start from the exhaust. I pulled plugs and they were wet with fuel. It ran very rich too. It was just a crank problem. If you ran it then shut it off, then tryed to restart it flooded and would not run at all. But if I let it sit for 1/2 hour then foot to the floor while cranking, it started.

Well I saw that the Green/light green wire had 4.88 volts. I dissconnected it from the pcm and checked voltage on that wire on the main harness. It was zero. Then I plugged the tps back into the harness and I had 5v on orange and green wire. The green wire is still dissconected from the pcm. One of the guys checked the TPS and it was screwed. I have ordered a new sensor from Ford.

I went over all my repinning. The only thing I forgot to do was move two wires to the new location. But that was just for the tab/tad solinoids.

I still cannot communicate with the pcm yet. I think that the self test connector may need to be cleaned up. It is not corroded just old and guessing that it has never been scanned for codes in a long time.

I will keep you updated.
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #5
Quote from: 86caprirs;325700
So i tryed to adjust the tps and I found that all 3 wire to the tps were at 5 volts.

The only way you can get these readings is because there is no current flow through the TPS. You are reading the voltage through the TPS, so what you are missing is the ground (ie the Sig Rtn BK/W wire).
If you had your meter on the TPS side of the connector when you measured 5v on the BK/W wire then the connector could be bad.
Bottom line, the BK/W wire should be ground but is not connected to the chassis of the car, it goes to pin 46 of the EEC.
Check that the small "pig tail" wire on the negative battery cable is connected. This is the ground for the EEC electronics.

Quote from: 86caprirs;325847
I still cannot communicate with the pcm yet. I think that the self test connector may need to be cleaned up. It is not corroded just old and guessing that it has never been scanned for codes in a long time.

The BK/W Sig Rtn wire also goes to the test connector and a code reader will not work without it.
With the TPS connected see if you have 5v on the Sig Rtn wire at the test connector. If you do, that's your problem, it should be ground.

Engine electrical help

Reply #6
Well I checked signal wire to ground. Thats was good. I also isolated the signal return wire and checked continuity. It was less that an ohm. I have a friends A9L that i will try in my car and see if I can comunicate with it.

I don't know where else to start. This is the original 5.0L tbird harness modified to run mass air. The wires should be all good.
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #7
Quote from: 86caprirs;325969
Well I checked signal wire to ground. Thats was good.

Checked it how?
With a volt meter?
With the TPS connected and the key on?
The result was 5V or 0V?

Did you check the pigtail wire on the negative battery cable?

Engine electrical help

Reply #8
I checked it to ground on the battery. It was open. I dissconected it from pin 46 (i think) and checked continuity on the signal return wire to the self test connector. Wire was .05 ohms. Then I went to the tps signal wire plugged in and dissconnected the signal return for the tps at the pcm. Ignition on i had 5v feeding back to the pcm by the signal return wire. I took the reading at the pcm connector. Then i dissconnected the tps at the connector and did an ohms reading on the signal wire to pcm. Less than a ohm. I am guessing the tps has shorted internally. I have one ordered and on its way.

I have also removed and cleaned all grounds within the cars body harness and engine harness.
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #9
Hi 86caprirs, you might be interested in my youtube video clip on checking the EEC4 TPS. It should give a better understanding of the voltages you should have. Just go to youtube and look up badshoeproductions
Ken Collins, BadShoe Productions
How To Videos specializing in Ford powertrains

Engine electrical help

Reply #10
Quote from: 86caprirs;325981
I checked it to ground on the battery. It was open.

You checked for continuity from the BK/W wire on the TPS to the negative battery terminal and it is an open circuit?
If so, this is BAD.
Did you check that the little pigtail wire on the negative battery cable is connected?
Quote
I dissconected it from pin 46 (i think) and checked continuity on the signal return wire to the self test connector. Wire was .05 ohms.

This is GOOD.
Quote
Then I went to the tps signal wire plugged in and dissconnected the signal return for the tps at the pcm. Ignition on i had 5v feeding back to the pcm by the signal return wire. I took the reading at the pcm connector.

This is GOOD.
It's normal to see the 5V feeding through the TPS on the sig rtn when the wire is disconnected from the PCM.
It is BAD if you see 5V on the sig rtn when the wire is connected to the PCM.
Quote
Then i dissconnected the tps at the connector and did an ohms reading on the signal wire to pcm. Less than a ohm.

This is GOOD.
Quote
I am guessing the tps has shorted internally. I have one ordered and on its way.

Bad guess. A new TPS is not going to fix this problem.

The ground for the PCM electronics is the little pigtail wire on the negative battery cable to pins 40 & 60 on the PCM.
I think if this ground is open, the PCM would not be able to pick the fuel pump relay. But it may be worth checking anyway.
If the PCM ground is good then the PCM is BAD.

Engine electrical help

Reply #11
Well the little wire to the battery is connected and also connected to the body. I checked the connector that is between the little wire and the body to make sure no corrosion is there. It was good.

When the pcm was in tact, I tested signal in the test BK/W wire connector too the battery, the ohms said open. No continuity. Then I isolated the circut and tested the wire. I am wondering about the pcm too. I have a good one to check with when I get to work monday.

When I removed the tps and checked the ohms, it was 500ohms off idle, 2500 ohms at 1/4 turn then open the rest of the sweep. Thats why I am replacing that part.
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #12
OK. I watched the video on the TPS setup. At rest the tps was 5.08v orange wire, 4.88v black wire and green wire was 4.88v. So almost 5v on all of them. I did a sweep test watching the green wire and no change at all.
1988 Thunderbird Sport. Work in Progress
5.8L swap w/fitech efi, 4R70W swap w/quick 4 controller, 2003 GT rear diff, 5 Lug swap

Bought this car back as an old project car.

:burnout:

Engine electrical help

Reply #13
did you disconnect the vacuum line from the map sensor and plug it?

if not do so


and i see in your profile your useing  a C&L meter.. are you useing the right sampling tube for 24's if your useing the 19 pound one it will run real fat
Quote
there's only about a half a dozen man made objects that are herd by the human ear below 40Hz,a pipe organ,thunder,the space shuttle lifting off,a jet airplane taking off or landing,a large canon,an atomic bomb ignited in your back yard and the heat wave afterward oh wait you would be dead so you would'nt hear it scratch that!,and maybe beating your hear against a wall less then 40 times a second..rap music is'nt one of them!thats 40-60Hz@100+db the moving air is under 40Hz

Engine electrical help

Reply #14
Ok at the begining of the video clip I say to check continuity from the sig. return wire at the TPS to battery gnd. Did you do this and did you get a open. If so, pull the PCM's 60 pin connector and check continuity from the 46 pin (sig. return) of the harness to battery gnd. If it has continuity, you have a burnt out sig. return connection in the PCM. A tip here is to check continuty from the the sig. return wire at the self test connector to battery gnd. If it's good, it's likely good at the PCM which again means you have a bad PCM. A damaged PCM on pin 46 may be caused by a stick shift PCM hooked to an automatic EEC wire harness. The stick PCM's don't always have a diode in the pin 30 circuit to protect it during startup (which can short out the sig. return).
Ken Collins, BadShoe Productions
How To Videos specializing in Ford powertrains