Can any one help me install a rpm gauge in my 91 E 350 diesel .I found a harness plug not being used behind the speedometer and I was wondering if I can tap off of it rather then running a wire off the alternator . I have a photo of it but haven't figured out how to post it here , the vans did not have a rpm gauge on there dashboards but the harness is the same on the diesel pickup trucks and they have it.On the right side of the oil fill there is a sensor for the rpm / timing can it be tapped here? Any help or questions welcome. I have been driving this van 21 years and not ready to park it yet.

 

My '84 doesn't have a tach either... I'm currently trying to figure out how to do this too. All I've been told so far is that it's easier to put an entire gauge cluster in rather than just the tach alone. This might not be true, however, it's just what I heard. Good luck, I'll be watching this thread with interest.

 

Its not true, I put a tach gauge in my 84 before it was wrecked....and i made it work too...pm me and I can walk the both of you through it...fair warning, the easy part is getting the tach gauge installed.

 

So I have a gauge ,and mounting is no problem making it glow like the rest of the dash is simple. What I'm looking for is where do I tap into ,there is a rpm sensor on the top right side of the oil fill . Can it be taped here?------I know the wire harness is the same on the pickups and van that are diesel ,so if I could figur out the colors that they use on the pickup trucks I would use it rather then route new wires inside...there are two plugs in back of the dash for the cluster only one is being used the 2nd one is not but has jumper wires on 2 lines 1 is red and 1 is green ,I don't know what this plug is for I do have a picture of it that I can share

 

https://www.ford-trucks.com/forums/1...l#post10674174 Click on this link for how to post pics.
Aune, Gary doesn`t have enough posts to use PM.

 

Oh my bad...i can write it up and post it, working on my IDI at the moment...will be done shortly.

 

Ok just a little different I have my 86 and it has stock tach and sensor but I can't get the thing to work and idk y before engine swap it was close but bounced a bit and after swap it doesn't even twitch I can't figure out why

 

I might just be your tach sensor in the ip gear cover, causing your issue.

 

Its probably your sensor itself is bad...they can come bad from the factory.

 

Ok, I'm not real clear what the question is here. Are you talking about installing an aftermarket tachometer or putting a stock unit on a vehicle that didn't have one?

The stock sensor on these is a magnetic pickup off the injection pump drive gear. It *should* output 68 pulses / revolution but it's a very low voltage AC signal. Clean connections are critical. Also, the sensor must be installed properly and clean. It's pretty easy to break the wires where they enter the sensor as well, so be careful. If there's any doubt, Ohm out the sensor, you should have somewhere around 1K-100 ohms resistance. (not exactly sure, if it's >1K or <10 the sensor is probably bad) Since it's magnetic, you can also get metal chips or scum stuck to the face which can degrade the signal.

You cannot use any sort of gasser tachometer off the stock sensor. You can use an alternator tach but you have to disassemble the alternator and tap one of the output leads before the rectifier.

A programmable tach (ie, ISSPRO R5535M) will work well with the stock system, but is expensive.

I'm not sure which leads on the cluster go to the stock sensor, the best bet would probably be to just ohm them out.... Or run new wiring.

Installing a tach shouldn't be too hard depending on what you're trying to do. The stock tach is a bolt in, aftermarket should just be some wiring unless it's alternator driven.
~John

 

To my knowledge the 91 diesel vans did not have a factory tach in them! No place on the cluster for it,but the f pickups did ! The wire harness behind the cluster looks to the same on the vans (E)class and pickups (f)class(Diesel)here are 3 pictures of connector's in the back of the cluster in wirelalaland Wish they had put numbers on the connector's for reference !What is this plug for andthebypass?http://i1151.photobucket.com/albums/...t/9bd5c564.jpg
On this one the plug on the right side goes to the Gauges on the cluster http://i1151.photobucket.com/albums/...t/7bcf31de.jpg and this one has power on three wires and ground on the 4th , http://i1151.photobucket.com/albums/...t/d15fc61c.jpg so the Qestion is what wires do I use to hook up a aftermarket tach ? 1 wire goes to ground and 2nd goes where ? Any one have a picture or diagram or know the color of the wire? Allso for the elect brake controler I have read here some ware not to get brake feed from the pedle switch do to the abs system
any one know the color of that wire and location of the conector ? Other then its under the dash angain I'll be back in lalawireland pictures are worth a million words ...If it was easy I would have done it 21year ago when I first got this Van just not ready to park it yet!!! The 01 ex is parked 61,000 miles and
bad mechanical diode no trans..........

 

From my installation sheet for my brake controller:

For 1989-91 Ford E and F series trucks and vans with anti-lock brakes:

Find the crescent shaped connector located on the steering column (turn signal harness). The connector has two rows of wires, one row has four wires (inside row) the other has seven.

The wire needed is the light green wire, second in from the row of seven.

Using the wire tap provided, splice the brake control's red "STOPLIGHT" wire to the light green wire.

As to the tach, I need to see if I can find my copy of the wiring diagram to see if we can help you out with that one.

 

I have that blasted thing somewhere greywynd....you sent it to me when i did the tach on the 84...

 

Greywynd , your the MAN...Next time up there visiting the family in Bradford or Newmarket I'll have to send you a message and is on me!

 

Where's home for you? I'm over into Markham/Toronto area quite a bit for work.

Still trying to figure out where my wiring diagrams are to see if we can help figure out the tach wiring for you, I think maybe my hard copy is hiding under a seat of one of my trucks, been months since I've used it.

Ahah!!

Just for *****s and giggles, I grabbed my Haynes manual, and even though it's really for gassers, it has the wiring diagrams for diesels in it!! Now, this is F series, but I suspect that the colour codes would be the same for vans, but no guarantees!

Now I don't think you posted what tranny you have either, so maybe it can change there, I don't know yet.

One diagram shows an 'engine speed sensor' (assuming that is the tach sensor) and that it has a blk-yel, and a dk grn-yel pair of wires. With the E40D, both wires go into the TECA (trans elec control assembly.)

At the dash end, the tach shows three wires going to it. One is shown as 'A-13' is red-yel, and goes to fuse #18. (That's a common feed for several of the gauges, btw.)
B6 is a tan-yel, with diesel, w/E40D, it goes to a wht-pnk, which then goes to TECA pin #36. Without the E40D, it goes directly to the engine RPM sensor, and then the other lead of that sensor (dk Grn) goes to ground.

Back to E40D's. The two tach wires going to the TECA. The dk grn-yel changes to tan-yel, which then goes to teca pin #4, rpms +.
The Blk-yel switches to dk grn-brn, and goes to pin 44 of the TECA, which they call rpms -.

Not sure if that will help you, or confuse the heck out of ya.

Seems to me that on the clusters I've pulled, there were two large connectors, one each side of the speedo cable. I wonder if the one with the jumpers is for 'optional' gauges, and the jumpers bypass a couple of them if they aren't there? Trying to see if I can find any indication of which of your connectors do what, but not finding that out yet.