Tachometer while cranking question
#1
05-27-2012, 11:06 PM
Tachometer while cranking question
So I'm dealing with a crank no start issue and have a question. Shouldn't my tach be registering some rpms while cranking? While cranking my tach does not move at all, no rpms. I haver a code reader that displays live data and it is showing about 160 rpms while cranking but nothing on my tach.
If this should be registering what would cause that failure? Would it be the crankshaft or camshaft sensor?
Thanks for your help.
If this should be registering what would cause that failure? Would it be the crankshaft or camshaft sensor?
Thanks for your help.
#2
05-28-2012, 09:03 AM
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#3
05-28-2012, 04:32 PM
#4
05-28-2012, 04:45 PM
Check this video. At 0:30
6.0 Liter Ford Powerstroke - High Pressure Oil Pump & Revised STC Fitting Part 1 - YouTube
6.0 Liter Ford Powerstroke - High Pressure Oil Pump & Revised STC Fitting Part 1 - YouTube
#5
05-28-2012, 06:19 PM
I just walked out and checked mine, The TAC stays on 0 until I release the key from start, So during crank it is on 0. If I leave it in gear and turn it to start the tac stays on 750 RPM even if I rev the engine. SO the tac works only in the run position, not the start position.
#6
05-28-2012, 06:21 PM
#7
05-28-2012, 06:31 PM
Here is a good way to check your cam sensor and crank sensor signals to the pcm. This is a quote from M-chan68 so he gets the credit.
here is a link to the pcm connectors. It's the middle connector plug #C1381t
https://www.box.com/s/38db5e11b446942bcf7d
f you want to verify those circuits, you can connect a DVOM to both the CKP and CMP circuits of the middle PCM connector. Set your DVOM to Hz. On the CKP circuit, you should be seeing 150 to 200 Hz when the engine is cranked over (directly proportional to 150 to 200 RPMs). On the CMP circuit you should get a reading of 1.1 to 1.9 Hz when the engine is cranked over. Hopefully you won't have to go this far before you resolve your issue.
https://www.box.com/s/38db5e11b446942bcf7d
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#9
05-28-2012, 08:17 PM
I just walked out and checked mine, The TAC stays on 0 until I release the key from start, So during crank it is on 0. If I leave it in gear and turn it to start the tac stays on 750 RPM even if I rev the engine. SO the tac works only in the run position, not the start position.
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