05 Ranger TDI conversion

[Evguy1]

Hey RonD do you have the rest of the engine wiring schematic that you could post?
The transmission one pointed out a couple of pin differences compared to my schematic and there may be some differences in the rest as well.

 

[RonD]

What year specifically is the wiring harness and computer?

This is in the speedometer section:

Starting in 2001, the Ranger gets its raw speed signal from the OSS (Output Shaft Speed) sensor on the transmission/transfer case. The OSS sensor is a magnetic pickup that provides transmission output shaft rotation speed information to the PCM (Powertrain Control Module) where it is corrected for tire diameter and axle ratio.

The PCM uses the OSS sensor signal to help determine EPC (Electronic Pressure Control) pressure, shift scheduling and TCC (Torque Converter Clutch) operation. The PCM outputs the corrected VSS pulse to the speed control and the cluster. In this system the PCM is the correction and distribution point for the VSS signal.

And I found this: http://beta.askatech.com/askatechlive/aatfileshare/references/fasttrack/F080.pdf
2005 ranger uses pin91 and 84 at PCM(2 wire OSS), but earlier models('96-'01) use a VSS(3 wire) and different pins, so your PCM may not be able to detect OSS sensors signal

These are the 4 engine control diagrams for 2005 3.0l:

 

[Evguy1]

Thanks for the info.
When I connect my Auto Enginuity software and check the vin it does come up as an 04 Ranger 3L.
When I drive it the PCM is outputting a correct MPH to the software just not making it to the speedo yet if I feed the speedo a signal from a signal generator it does work.
I'll go over these schematics and see if I can find the problem.
I did have to move the OSS pins at the PCM (to pins 91 and 84) to get a signal.

 

[Evguy1]

Moved the speedo output from pin 86 in my schematic to pin 96 in your schematic and now I have a speedo.
I think/hope crank sensor signal is the only thing left to fake.

 

[RonD]

Good work

 

[Evguy1]

Good work

Thanks but not so quick.
It has speedo and shifts not bad and downshifts when you put your foot into it.
It shifts real hard if you have your foot into it and at too high of an RPM.
I still don't have the warm and fuzzies over this but its getting closer.
I'm not sure what to try next.
I have a nice TPS input and all the transmission sensors are putting out the correct info.
I have a lame KPS signal and that may still be my issue.
I may need to bolt a 35 tooth sprocket to the front of the engine and install an actual KPS.
Is there any other input that I'm not thinking of?
I'm REALLY impressed with how much power this thing has, it should be a blast to drive once its running right!

 

[RonD]

What you may have to do is give the computer a higher false RPM because for the lower TDI RPM power curve.
Computer expects 3.0l power curve and is setup for that, which is based on speed, RPM and TPS(throttle position).
Speed and TPS are the same for TDI or 3.0l, but RPM power curve is lower for TDI so shift points need to happen at lower RPMs, by feeding false higher RPMs shifts happen sooner.

What are you using to generate RPM signal for computer?


Dakota Digital makes tach and speedometer interfaces, allowing user to change signal pulses to suit the need

 

[Evguy1]

I pulled a signal from the TDI crank sensor.
Then ran it through a Dakota digital tach interface and spent a LOT of time trying all the variables in the DD to get a reliable signal but nothing worked.
I changed to the DD speedo module ( I stock both) and finally got an weak signal.
Its intermittent and will fluctuate from close to correct RPM, then to a few grand over and all the way down to zero. I think this wildly fluctuating signal is a problem. The tach jumps all over the place.
I wish I had a scope to look at the signal and see what its actually doing.

 

[RonD]

I think Ford still uses a VR(Variable Reluctance) CKP sensor so this article may be helpful: http://www.dainst.com/info/edis/edis.html
VRS is a 2 wire sensor with a shield wire as the 3rd, VRS generates it own power, usually AC power under 1 volt

What kind of sensor does the TDI use?
EDIT: looked it up but not sure on the engine specifics, shows VW using Hall Effect sensor so Ford PCM wouldn't understand it
Hall effect is a 3 wire sensor, it requires power, ground and signal(return) wires.

Ford used the stand alone EDIS module until 1995 then moved this spark control into the PCM when the new EEC-V was installed

You may be able to add a tone ring and CKP sensor to an accessory pulley temporarily to see if it works, #1 TDC won't matter since it isn't controlling spark or fuel.
You also get the higher RPM from smaller pulley

 

[Evguy1]

A stock Ford sensor arrived today and I have a 36 tooth (one to be removed) steel sprocket coming later in the week and we will bolt it to the TDI crank pulley.
I'll machine off the tips of the sprocket to give a wider sensing area. Hopefully the rounded tooth bottoms are not a problem or there will be a lot of filing done to make them squared off at the bottom.
I hope that will solve the last shifting issues.

 

[Evguy1]

While I'm waiting on the sprocket to arrive I'm trying to tie up some loose ends.
On older Rangers you could set the tack to 4,6 or 8 depending on what pins you grounded at the cluster.
Is it the same on the 05? What pins? I can only find info on the older trucks.
Is the temp gauge a 0-5V or a grounding resistance?
Temp gauge wire color where it comes out of the cluster?

Thanks for any input.

 

[Evguy1]

Got a 36 tooth sprocket and machined off the tips to make a close facsimile of the stock tone wheel.
Took out one tooth so it was the 35 +1.
Fired it up and got 900RPM on my OBD2 scanner software. The tach is running direct from the TDI ECU so I could not just go by it.
I wanted to see what effect the skip tooth had so we welded a tooth back in and it made no difference to the reading. This was important, the ECU is just counting teeth and not counting from the skip tooth so I can use any number of teeth to very the RPM reading.
I wanted to try and fool the Ranger ECU to thinking I had a higher RPM to get it to not shift at such a high RPM so we tried a smaller sprocket with less teeth.
Wrong way, RPM dropped to 550 on the software.
Went up to a 42 tooth sprocket and now I have zero RPM showing.
Its the same series sprocket as the 36 tooth one so spacing is the same. I machined the teeth off the same amount so they have the same amount of flat surface to trigger the pickup.
The sensor is the same 1/8" away from the sprocket yet I get zero RPM.
Every couple of starts it will briefly show an RPM but then drops to zero.
One step ahead, two steps back.

 

[alwaysFlOoReD]

One step ahead, two steps back.

Only when you're lucky...

 

[RonD]

According to what I have read the TDI would idle at around 900RPM
So I assume the added 36 tooth wheel is on the crank and CKP sensor is detecting correct RPM.

ECU is set for 1 tooth every 10degs, so 36teeth = 1 revolution, especially if the missing tooth didn't matter, which surprises me, with no reference point it must just assign #1 to some "flaw" in the wheel, and then count to 35 and reset, and count 1 revolution, if that "flaw" is seen again at 36 then it repeats, creating a valid RPM

If this is the case then the 42 tooth wheel would cause 0 RPM because ECU is assigning #1(flaw) but 35 count doesn't match when assigned #1 comes around again.
And that would fit with the brief showing of RPM then 0, the computer is running a sanity check with 35 and it doesn't pass.

Any wheel spinning at these speeds will have a reoccurring pattern of pulses, that is the "flaw", takes a few revolutions for computer to see that "flaw" but it will and that is assigned #1 status, then the sanity check kicks in making sure there is a pattern of 35 pulse between assigned #1 if there isn't then 0 RPMs.

Not sure why the smaller sprocket worked though?
Unless it was 18 tooth

What about putting the 36 tooth wheel on an accessory pulley to gain the false higher RPMs?
8" pulley spinning at 900RPMs would drive a 6" pulley at 1,200RPMs

Or go to 72 tooth and use 2 missing teeth 35 apart, but, if it worked, that would put RPMs at 1,800 at idle so probably wouldn't be of any help

 

[Evguy1]

That's what it is.
I went back to my 35+1 sprocket on a new "Crank sensor testing machine" and it worked fine so it needs that skip tooth.
Not sure why the small 20 tooth sprocket worked. It was new with no missing or damaged teeth.