I think the fuel pump in my 2001 2500HD 8.1l is going out. What has me confused is which pump to get(mu1613, mu1614, AC, Bosch, Advance auto). I no longer here the pump kick in when I turn the key. I have to turn key on and off up to 3/5 times to get pump to come on. If I do not hear the pump, no start. I have had the cam and crank sensors changed, and she has 202,000 happy miles on her. Thanks for the help

Pumps coded TCU don't have a fuel tank pressure sensor. Pumps coded TCF do. Most emmissions trucks have TCF. You can feel and or look with a light and mirror at the pump cap on top of the tank. The code is printed on a round sticker on a round bump on it but you'll have to clean the dust off to see it. Or if you feel/see two separate wireing plugs or one. They both have three pipe connectors.

The pictures on NAPA's site are usually the best, they don't play around. www.napaonline.com You can use the "interchange" search to see which AC part#'s match witch NAPA pump pics if necessary. In my shop I try to use AC, Delphi, or NAPA for GM. Mostly NAPA due to the better warranty for us being a Napa Autocare. They pay labor claims against parts that fail under warranty. Airtex pumps have the highest failure rate in my experience, these are common low cost parts store stock, I will not use them anymore.

Vernon

It could be a ignition switch problem, I have had two '96 454's in here in the last month doing the exact same thing, and it was ignition switch.

Thank you for the help. I will add it to the list of many things to do tomorrow.