Background: This is a 2003 E-350 but it is built like a truck. I built an intercooler for it to handle the extra heat for the new KC300x,180/0 FFD injectors and PHP with Jelibuilt tunes and 4" exhaust. It has a boost fooler and EBPV/AIH deletes. I also built a 4x4 conversion, rebuilt the trans for the shorter output shaft and built it to handle the extra torque.

So here is the issue: When I put it in drive and ease into the throttle, as it starts to rev it just falls on it's face, almost stalling until I put it into neutral and rev it up to sort of "clear it". It revs to redline in neutral.

There are no faults in the ABS and new sensor in the rear axle, I will explain why that matters in a second. There are no faults in the PCM either. ICP is 500 psi at idle and the stock HPOP revs to 3000 psi. It has a new fuel pump, lines, tank, bowl and fuel pickup. Also when all this happens, the injector PWM drops to zero.

Here are the things I have observed: The speedometer is acting weird reads 3x the speed. The VSS is reading zero, it has a new sensor. I even scoped the hole to check if the tone ring was on the new (used) output shaft because the trans work was done last summer (I just don't remember). The TSS is reading fine. I haven't been able to find the technical documentation that fully elaborates on how the speedo get's it's signal. As I understand, it gets it from the ABS sensors, makes a calculation and sends vehicle speed to the units that need it. What I am guessing is, the super high speed signal is causing the PCM to freak out and de-fuel the system.

• I know I need to finish diagnosing VSS but Is it possible the 0 VSS signal is screwing up the speedo readings?
• Does it have influence on the ABS speed calculations and make the speedo go 3x fast?

This info lies deep in some Ford training manual that I don't have. I did see an ambiguous Econoline specific VSS signal in the block diagram in the coffee table book but it doesn't explain anything.

I guess Econolines also have some variations in the speedometer from F-series. A Ford tech friend gave me some vague info about it being an issue on Vans but he didn't remember. I may have to jump on the van group for that

 

Idle validation switch?

 

My 99&00 trucks speedo get the info uses the tone ring on the rear axle carrier to calc speed of travel.
It almost sounds like your tc is locking as soon as a gear is selected, stalling your engine

 

A couple of years ago there was a fella with a bus or van conversion that had a similar issue, I'll see if I can find it and link the thread here.

As mentioned above, the trucks speedometer is run by the VSS on the rear differential.

I bought a copy of the Ford manual you referenced, as many others have. I'll see what I can find in there too.

 

I found the link to the thread, but reading over it, you are not having the same problem. Perhaps there is a nugget of information in there though that will help you out.

Link: https://www.ford-trucks.com/forums/1...ss-issues.html

Also, pertaining to the FSM (Ford Service Manual), see the link below. I can search and look through the manual all day long and not know what it is you are looking for. I will still go to the E Series section and see what I can find, but I might be looking for the wrong thing or not know what I am looking for.

Link: https://www.ford-trucks.com/forums/1...l#post20254002

 

Is the vss oem or aftermarket?

 

OEM and I checked the part number too

 

I know the fuel parts are mostly new, but a fuel pressure reading would cut diagnosis in half.

 

Yeah, I am going to measure it when I get the fitting but I doubt it is a fuel problem, the only old parts (82k miles) are the injector cups and the lines that run up the block to the fuel bowl. I retrofitted a 55 gal RV tank so EVERYTHING else is new from the injectors back.

It is looking more like a transmission signal problem, TSS signal is lost and the converter locks up when on when it stalls, the speedo reads 3x so it locks up when the it reads 60 mph even though I am barely going 20.

 

Thanks for finding this, there is a lot of interesting info to chase down here. I have determined the speed signal on a Van is from the VSS based on the factory wiring diagram unlike the trucks which come from the ABS. The only signal for ABS to the cluster, is a warning light. Which might indicate the wild speedo readings are an issue.

 

Thanks. Based on your input, I read PIDs on a test drive yesterday and looked at TCC, it is locking up when the stall happens when the Speedo reads about 60 (even though I am barely at 20). I think the PCM is doing it's job but there isn't fault code. The fault code table in the coffee table book doesn't have a code for it so I think the PCM doesn't recognize it as an issue because it is not part of it's parameters.

Swapping TSS and VSS sensors and rechecking next just to verify parts.

 

Do you know if there is a PID for that? I will check it.

 

There is, I believe it is an ON/OFF. I am not sure on the reading, but I am sure there is a PID that is capable of being monitored in order to verify the IVS is functioning properly.

 

I have validated my suspicion in order to help you find a path to successfully repairing your issue.

In this post AmryLifer (Eric) mentions he added the IVS PID. I scrolled a bit further down to this post where you provided the .csv file showing the IVS PID and what it displays.

You are able to see it in the last column which I have highlighted.