No Tach while cranking...

[partsguy84823]

First off, my truck cranks, starts, and runs just fine.

BUT I was reading a post a while back about a 7.3 that was a crank-no start condition. One of the sugestions was that the owner look at his Tach as he was cranking to truck over, the thought being if the CPS was sending signal that the tach would register some reading.

I got curious, and I looked at mine the other day while it was cranking, and the tach stayed at 0 until the engine fired... is this how its supposed to be, or should it move?

[GotDiesel85]

yes its normal

[NoRalPh]

I think it works like this....

Sometime in like, 2001, the instrument cluster was redesigned and a Trans Temp gauge was added. If you've got the gauge, and an '03 certainly does, then the electronics in the new cluster no longer shows cranking rpm on the tach.

Before that, it's an indication that the sensor (the, infamous, CPS) isn't sending a pulse and therefor Bad...

[partsguy84823]

Sweet... yeah, I knew I had the "new" cluster (with the trans gauge). I just didn't know that it wouldnt show cranking RPM. Thanks a lot.

[Zaairman]

My tach has never ever moved during cranking, unless it's an extended crank, like when I had a bad battery in the winter and it'd basically crank for 10 seconds and die.