Just started on my way into work tonight, but my check engine light came on at the same time that my Tach will go to zero. It stayed at zero for 10 minutes of so, then just magically come back up to regular readings?

I'm leaning toward the Crankshaft position sensor, but wanted to get the consensus of this knowledge base.

All other dash instrumentation is performing as expected. And the EGT, Boost, and Tran Temp cluster is reading norm.

p.s. In the parking lot I did the turn on/off trick to get the codes and I'm pulling a 1693 and no other codes.

 

1693 I believe is a companion code and has something to do with the inj pump, but your symptoms sound like the crank position sensor, or a cam position sensor might be at fault. Maybe someone with more savy than I can better define your problem.....

 

Thanks for the reply! The more research I do tonight, the more confused I get.

I'm not sure if I should start with the CKP Sensor or CMP Sensor?

As a side note, it did not appear to lose any power when it dropped the tach so maybe I'm way off base.

 

What year is your truck?
My 01 did the same thing, it was the cam sensor. Get the codes read with a scanner.

 

Year =2000

Read codes w/ Scanner and pulled a 0336. I have new sensor in hand and will work to replace in the morning when I get off of work.

 

Looks like the crank sensor. Good luck.

 

Changed the crank sensor out this afternoon, and we are back in business! Thanks for all the help! This forum saved me a ton of time and $ chasing my tail.

- jonathan