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Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8963
Experience:  I am ASE Master Truck Certified.
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Me again. Wired up timing sensors (soldered ). Truck cranks,

Customer Question

Me again. Wired up timing sensors (soldered ). Truck cranks, you can hear things clicking in engine department with key on, never fires. I figured timing sensors and wiring was my problem but still no start. This started out as a random engine dying while idling
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Expert:  Cat Man replied 2 years ago.
Hi. Thanks for asking your question! I will try and help you out.
Does the yellow check engine light come on when he key is turned to the on position?
Customer: replied 2 years ago.

Yes, but it goes off in short period of time.

Expert:  Cat Man replied 2 years ago.
Thanks for the information Sue.
If the light comes on, the ECM is receiving power. So next I would like to try and pull codes by using the cruise control swltches. If you have never done this. Here is how.
Use the following procedure to retrieve the flash codes from the check engine light:
Turn the ignition key switch to the On position/ Engine OFF.
Turn the cruise control ON/OFF switch to the OFF position.
Move the SET/RESUME switch to either position. Hold that position until the yellow lamp begins to flash.
The yellow lamp will flash in order to indicate a two digit flash code and the SET/RESUME switch may be released. The sequence of flashes represents the system diagnostic message. Count the first sequence of flashes in order to determine the first digit of the flash code. After a two second pause, the second sequence of flashes will identify the second digit of the flash code.
Any additional flash codes will follow after a pause. These codes will be displayed in the same manner. Flash Code 55 indicates that No Detected Faults have occurred since the ignition key switch has been turned to the ON position.
Let me know what two digit code you get and I can tell you what the problem is.
Customer: replied 2 years ago.

Don't have cruise control.

Expert:  Cat Man replied 2 years ago.
Oh I see.
There are many things that can cause a no start on these engines. The most common is a problem with the injection Actuation pressure system that activates the injectors. I see this a lot. But to confirm the codes will need to be read in the eCM. Without cruise control switches. A service tool like Cat ET software or Prolink will be needed. I am sorry. I wish i had better news.
Please reply back if you need more help or have more questions. I am happy to assist.
Customer: replied 2 years ago.

What are the odds of a bad ecm or is it more likely to be IAP? I am 65 miles from nearest Cat dealer. 1 local shop is too busy to get here today. Another tech has Cat ET but he doesn't have OBDII. He didn't think he could read it with Cat ET since it is in a GMC truck.

Expert:  Cat Man replied 2 years ago.
Hi Sue.
Actually it could be an ECM or the IAP. If the IAP sensor is bad, you should be able to unplug it and the engine will run. If you have a HEUI pump failure or leaking injector. It will not run. If you have a leaking injector, you can pull the valve cover and crank the engine. If you see an oil leak at an injector, that's your problem.
ET can connect to a GMC but you'll need the GM connector.
Please reply back if you need more help or have more questions. I am happy to assist.