I have a 1994 f-250 extended cab long bed 2wd 460 with 215,000 miles. the tachometer does not work it just stays at 0 rpm, it did not work when i bought it last year either. any ideas on what could be the problem?

 

The VSS might be umplugged or damaged, or the rear differential was rebuilt and the didn't place the ring that works with the VSS. For the VSS, search around your rear diff. for anything that looks like a sensor. Your tach could also be gone, but i would check the two other options first.

 

Thank you for your input. I crawled under the truck and located the sensor you were talking about. The wiring was still attached and I followed the wires for as long as I could and there did not appear to be any problems. My guess should be that the sensor has been damaged?

 

uhm the tach not speedo

check the reluctor ring and the magnetic pickup in the distributor then check the wires

 

VSS? You thinking speedo?

For the tach check the white-pink circuit for continuity between the ignition suppression resistor and the tach end connector, as well as the connections at each end for corrosion, if that all tests/looks good you probably just gotta dead tach.

Might be a fault in the TFI module but you should be throwing an error code for IDM failure if that was the case, 212 for example.

 

I think I may have found the problem. I checked under the hood and the pink and white wires looks good. But I found a black wire that is completely broken, I had never noticed this before (although I did not know where to look). I took some pictures of the problem. Could this be the reason my tach is not functioning??

http://s231.photobucket.com/albums/e...h.jpg&newest=1

tach2.jpg picture by tpcgreg - Photobucket

 

Oh sorry, i got confused, follow the other guy's advice, i was in fact thinking about the speedometer when i wrote my answer...

 

No problem

 

That's not a wire its a vacuum line, plug it back in.

Next to the red one on the vac booster tank.

No, no effect on the tach.

 

Can't, it's broken. It won't plug back in.

Does anyone have an idea on how much a professional would charge to fix the tach? Just a general estimate.

 

Oh didn't see your second picture, you can pull the broken piece out of the rubber and reinsert the line back into it. The barbed end will be lost but it will stay in place ok by itself. If you're not to happy with it like that you can apply a little silicone on the end of the line and then push it in place. Once the silicone sets up over night, that will hold it.

 

oh ok, that was helpful. Thank you