found motor oil in my distributor

broncobuckinaround · Jul 5, 2015

I've put another pcm in it. Tps is new. But I will do this test in the morning. I will write back on this early. Like 730 my time. I live in utah

broncobuckinaround · Jul 5, 2015

ok well I started it and warmed it up. and of course the pcm grounded the wire. so when I saw it did I unplugged the tps and tested again and no light. tested voltage like you asked. .8 volts closed 4.9v wot. tps is good. so this would indicate that there is a problem in that circuit. there's a few other things slipced into that circuit.

RonD · Jul 5, 2015

Here is the pin out for the EEC-IV: http://www.auto-diagnostics.info/ford_eec_iv
Pin 53 is the TCC Ground but not shown on this

And the electrical diagram of 2.9l: http://www.therangerstation.com/tech_library/EDiagrams/files/Diagrams_ElectronciEngControls2_9_2of3.JPG

And here, showing TCC at pin 53: http://www.therangerstation.com/tech_library/EDiagrams/files/Diagrams_ElectronciEngControls2_9_3of3.JPG

TPS and MAP sensor share 5volts from computer, pin 26
Pin 47 is the return voltage you tested.
Pin 46 is the common ground for several sensors, this is a reference ground passing thru the computer so should be tested.
You could test this by using the lower wire on the TPS, the ground from pin 46, and see if voltage on center wire is the same as when testing using an engine ground.

Which reminds me, on the back of the head there should be a Ground strap going to the firewall, this is the main ground for the cab electrics, and is often left off after engine work, make sure that ground strap is there, or add one.

Pin 30 is a trans neutral/in gear sensor, but can't see where it is suppose to get its 5volts from, I assume pin 26 but don't see it in the diagram, so could be incorrect reference.

Is the new computer from an '86?
or could it be from a later model that is looking to control a 2nd trans solenoid?

broncobuckinaround · Jul 7, 2015

ok Ron. sorry it took so long. but I tested the wire. it has the same as battery ground.

so this means ground is good right. and the ground strap is there.

RonD · Jul 7, 2015

Yes, should be fine then.

broncobuckinaround · Jul 8, 2015

what's next. can a faulty map confuse the pcm that there is a greater load than there is.

RonD · Jul 8, 2015

Yes it could, but MAP sensors rarely fail, not never just rarely, and usually it would be a total failure with CEL on.

Good read here on Ford systems, older and newer: http://oldfuelinjection.packrad.net/

broncobuckinaround · Jul 8, 2015

so where does this put us as far as farther diagnosing it. anything else to look at

RonD · Jul 8, 2015

Well as far as I know you have moved on to different problems from the original question, so not sure?

I think the original problem was A4LD trans acting up:
You have an early model A4LD trans with 1 solenoid, TCC lock, 2 wire.

I read in another of your posts that you didn't have an '86 computer matching the '86 trans, it was changed to later model computer.
And that later model computer could be for a 2 solenoid A4LD trans(3 wire), which could be the problem, I don't have an answer to that situation, if that is the case?

broncobuckinaround · Jul 8, 2015

I've been putting everything back to n original. so just imagine that it's an 86 b2 a4ld. and the tcc is locking up,when it's not supposed to. I'll make another post if it helps any.

RonD · Jul 8, 2015

And you are using an '86 computer?

broncobuckinaround · Jul 8, 2015

yes and it's for the 1 solenoid a4ld.

RonD · Jul 8, 2015

From what I read the TCC unlock/lock is based on Road speed(VSS) and Throttle position(TPS).

Not sure where the VSS is on the 1986?

broncobuckinaround · Jul 9, 2015

it's on the transfer case. I replaced it cause I was told it could cause a problem. and testing it was fun. lifted the rear wheels and checked for ac voltage and got none. so it's new the connector was shot so it's new. and the wires didn't have any protection also were twisted together. they go to the cruise control amplifier. but I don't see how that speed info in transferred to the pcm. there's no wires going to it. could the amplifier be bad. how do I test it.

RonD · Jul 9, 2015

Found this at The Corral, it is part of a MAP to MAF conversion How-to:

Hooking up Vehical Speed Sensor (VSS) wires(optional)
There is a differential signal called VSS (Vehicle Speed Sensor) which comes from a small sensor on the transmission where the speedometer cable is connected. In 1986-1988 MAP cars this signal was used only by the cruise control and the sensor may not be installed if your car does not have cruise control. In MAF cars, this signal is used by both the cruise control and the EEC-IV. The wires/pins for these signals are not physically equipped in a MAP car's wiring harness, which will yield an error code for NO VSS SIGNAL- (code 29) from the continuous memory codes in the EEC-IV. These signals are not absolutely needed, though some people have reported stalling when coasting to a stop without them. You can hook the VSS signals up to the EEC-IV connector by connecting the input pins of the EEC to the appropriate wires on the cruise control module (located just to the left of the clutch/brake pedals). You need to hook the dark green/white wire going to the speed control to pin 3 of the EEC, and the orange/yellow wire to pin 6 (these are the colors for an '88, anyway). These positions on the EEC connector are empty and will require 2 EEC-IV connector pins.

So still not clear on how the EEC knows when to activate TCC.
I think it would have to know when trans was in gear
And RPM (PIP from TFI)
Throttle position(TPS)
And vehicle speed, but above says no.

found motor oil in my distributor

Member

Member

Official TRS AI

Member

Official TRS AI

Member

Official TRS AI

Member

Official TRS AI

Member

Official TRS AI

Member

Official TRS AI

Member

Official TRS AI

Sponsored Ad

Sponsored Ad

Member & Vendor Upgrades

Truck of The Month

Recently Featured

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store

Sponsored Ad

Sponsored Ad

Sponsored Ad

Amazon Deals