Factory tach...
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Factory tach...
Ok guys, Im blue in the face from looking for wiring diagrams showing the tachometer wiring for the 1988 2.9 auto 4x4. Haynes, chiltons, nobody shows it. The deal is, my tach works once in a while, when it wants too. Most of the time though, it doesnt work at all. Should I just go aftermarket?
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From: Yokosuka, Honshu, Japan
Also check the wiring on your ignition coil... the tach gets its signal from the "tach" wire on the coil. Could also have a break / breakdown in the wiring between the coil and the tach somewhere (connector between the cab and engine bay, etc.). May have to go get a (hopefully) 100% working one from a junkyard, if the tach internals are toast. Hope this helps, and hope you get it fixed soon.
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Well, I looked on the coil, and I didnt see where the wires would have broken off toward the cab. Maybe I just need to look more closely. But everything in the dash seemed to look ok, but I think a volt/ohm meter would tell the tale. Say, you wouldnt happen to know which wire it reads from the coil, would you? Im baffled, and I guess I need to just dive in and spend some quality time with my truck!! LOL Thanks Kernel!!
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Dark Green w/Yellow stripe, which would be the coil primary's 'negative' lead, and there should be a "TACH" marked on that wire's side of the connector, if I remember right. That would also be the wire you would tap into for wiring up an aftermarket tach. You're welcome, steve!
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Actually Kernel, you'd be shocked if you saw the wiring in this little truck! LOL It was "modified" by a young guy who wanted to perfect all of Fords "shortcomings" in their electrical technology. It had little holes drilled in the fuse panel cover with little LED's, tiny toggle switches, etc. I think he was a NOT_SO_SMART James Bond wanna-be! LMAO!!! Anyhow, I have been "reattatching wires" from day one, but the instrument panel was something I didnt know much about. I installed a manual oil pressure guage the first week I drove it, and the temp guage seemed to work just fine. No working fuel guage or volt meter. And I think the kid had NO CLUE what real solderless connecters are!!! LMAO Its been fun, to say the least!!
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From: Yokosuka, Honshu, Japan
Those pictures would be worth 78493749382749382 words, I'm guessing. I always love going in after someone did a botch-job of wiring/re-wiring anything. The only thing that sucks is I'm not sure if Painless Performance sells a 6-banger fuel-injection compatible complete wiring harness or not, but my guess is a big fat NO. Sounds like you've been going over the factory wiring diagrams and doing a lot of hand-over-hand tracing and head-scratching (or banging, as the case may be!) on your truck. Hopefully, you get all the kinks worked out soon enough. Sounds like it's going to be a fairly long project, though... if only there were 96 hours in my day and I had time to take off and head down to TN... I'd help ya out!
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Well, I have been sleeping with my Haynes manual, and Im learning alot. Say, do you have a cell phone? I have a really cool new Kiacara camera phone, maybe we could chat sometime. And I could send you some pics of the "new" wiring harness the kid came up with!!! LMAO Anyhow, I chased all the wires for the factory tach, and its somewhere between the computer and the tach itself. The wires you described branched off the coil, and went over that way, so Im guessing, the computer has to do something with the signal before it goes to the tach?!?! Make any sense to you? Im shopping for a aftermarket tach and voltmeter, not sure about the fuel guage, might try replacing the sender in the tank, hope thats all to it.
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From: Yokosuka, Honshu, Japan
I think the wires pass through on the passenger's side for some(or all?) of the interior wiring, if I am thinking right. The computer takes the signal from the TFI module and then outputs the signal for the ignition coil / tachometer, if I'm not mistaken.
The fuel gauge could be bad wiring between the sender and the gauge or a bad sender itself. I have seen the wiring actually dangling loose from the sender / in-tank pump on a Ranger.... so, nothing would surprise me much.
OH, and yeah, I have a cell phone, but some days I'm running 849320843 different directions at once. It's good you're learning by asking advice as well as reading and hands-on, especially with a 'special project' truck like yours! I'd almost want to go find the kid and beat 'em within an inch of his life... would be one thing if there were NO issues with the truck and he actually made WORKING improvements, I guess LOL
The fuel gauge could be bad wiring between the sender and the gauge or a bad sender itself. I have seen the wiring actually dangling loose from the sender / in-tank pump on a Ranger.... so, nothing would surprise me much.
OH, and yeah, I have a cell phone, but some days I'm running 849320843 different directions at once. It's good you're learning by asking advice as well as reading and hands-on, especially with a 'special project' truck like yours! I'd almost want to go find the kid and beat 'em within an inch of his life... would be one thing if there were NO issues with the truck and he actually made WORKING improvements, I guess LOL
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I did trace the wire from the coil, it branched off, and it was showing good voltage. So, I guess I'll keep on looking, its getting interesting now!! LOL My little Bronco has been my daily driver for about 18 months, and has only let me down twice. Both times were fixable pretty quick. I love this little truck, its awesome to drive and the guys at the range where I shoot always google at me when I come pulling in. I am thinking about lifting it up a couple of inches, and running dual exhaust with some quiet mufflers. I'll have to take some pics and mail 'em to you, I think you'll get a kick out of it. It is a covert looking camo OD green and black with a brush guard covered with lights, its a real trip!! LOL If you ever get a minute or two, I'd love to hear from ya, my cell number is 865-455-0937.
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From: Yokosuka, Honshu, Japan
Hmm. One wire (red/green stripe) should be "hot" when the key is in the "run" position, and other wire (green/yellow stripe) should "pulse" and should only read voltage across the primary when the sensor/pickup/tfi module sends a negative voltage pulse to the coil, if I'm thinking right. I re-looked at the wiring diagram and the pulse is direct from tfi module to the coil, and should also go directly to the tach, but may also use another signal from the computer.
I like the camo paint jobs I've seen on some rigs... although, I am thinking of urban camo for mine... if I don't re-paint it to the original color scheme. You could probably post pictures to your photo gallery on here. I have some pictures of mine on here, as well as elsewhere. I've seen a LOT of BIIs around this area lately, and I try to hook up with the driver/owner when I can and talk shop.
I like the camo paint jobs I've seen on some rigs... although, I am thinking of urban camo for mine... if I don't re-paint it to the original color scheme. You could probably post pictures to your photo gallery on here. I have some pictures of mine on here, as well as elsewhere. I've seen a LOT of BIIs around this area lately, and I try to hook up with the driver/owner when I can and talk shop.
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Well, I didnt get any fluctuation in my reading on the green with yellow strip wire while running. But that doesnt mean anything, my meter might not be able to read the pulse. But I think the wire ( green/yellow) does go to the tach and the computer. I think each wire does its own thing, and the tach does read from a primary. But, its just so much fun, Im not going to get ahead of myself!! LOL
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From: Yokosuka, Honshu, Japan
Most digital meters probably won't read the pulse, you may need the right test lamp or an analog multimeter (i.e. Simpson 260 or similar). You can always get an aftermarket tach for the sake of testing the signal all the way to the instrument cluster, I guess!
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Yeah, I can do that. I just thought it would be nice to get the original tach going. But, Im off to go shopping, gonna see what I can find!! LOL Thanks Kernel, I hope you're having a good weekend.