So, I just had my Tranny put in (after my original zonked out on me) and now my tachometer doesnt work. I have checked the majority of the harnesses but im having trouble figuring it out. Any suggestions guys? I checked the fuse boxes both under the hood and inside the car, but none relate to the Tachometer. What am i missing?

 

The Crank Position Sensor is read off of the flywheel (the teeth on the flywheel)

More then likely you either put the flywheel in wrong, hit the CPS and made it so it can not read the flywheel anymore, or somehow the CPS went bad.

Either way, if the CPS is not getting a reading you will have difficulty starting the car and / or the tach will not work (atleast in my experience).

pmohr will jump in shortly (at some point) with more information

 

What Merlyn said.






Does it start up normally, or take forever?

Take a look at the CKPS POS, make sure you didn't damage it:

 

my car has a similar problem ,after i put my tranny in my tach works but my speedometer doesnt. Not tryin to change topic but i fugured since its close to what im dealing with i'll post here.

 

Checked the VSS?

 

i am actually having a ton of trouble starting the car as well.

 

Then yep, the CKPS POS is your problem.

Did you replace the flexplate, or leave it bolted to the crank?

Have you checked the CKPS POS? First, make sure it's actually plugged in. Then, check for metal shavings and debris on the tip of the sensor. Also check for any cracks or other damage to it.

 

Pmohr, im having a hard time visualizing that schematic....Is this from underneath the car? I know it says with under cover removed. Would it be possible to see this from a top view by opening the hood?

 

You could, yes.

Just look down along where the bellhousing and block meet, facing directly forwards pointing the radiator is the CKPS POS. You should've removed it when you did the trans work.

It's held in by a single 10mm head bolt.

FWIW the pic above is looking from underneath the car up towards the block/trans, with your feet pointed to the back of the car and your head to the driver's side of the crossmember.

 

VSS?

 

Vehicle Speed Sensor.

 

I knew that but ive got 3 from the junk yard already

 

So you've already tried replacing it, then? Have you checked the wiring, or checked the screw on the back of the speedo?

Does the odometer work?

 

thanks to all that helped gave input to this topic, particularly pmohr. It was in fact the CPS. It was bolted in all the way. Thanks, you helped a ton!