Needed to replace the Fuel Sending Unit on my 2005 Trailblazer. Ordered a replacement and installed it. Ran good for several days then would not start unless I primed it by turning the ignition on and off several times.

My mechanic looked it over and determined that the fuel sending unit was defective. I ordered a another and had it installed. Two weeks it ran fine. Now I have to prime it again to get it to start.

How can I get this issue resolved.

Also, does the computer have to be reset with the replacement of a fuel sending unit.

Thank you for any help with this.
Harley

 

When you say fuel sending unit, do you mean the fuel pump assembly? Have you been changing the complete fuel pump? It is not common for them to go bad that quick. If you buy the cheap off brand units they will tend to fail quickly. If after priming it the truck runs OK then the problem is with the check valve in the fuel pump. I have never had to reset the computer after changing a fuel pump.

 

oldchevy,

Thanks for getting back to me. What I have replaced twice is the unit the fits down inside the fuel tank. It appears to be an off brand as it cost $72. A name brand unit is about $400 at Advance Auto.

Can just the check valve be repaired/replaced.

Harley

 

oldchevy is most likely right, when you say sending unit. That generally refers to the float level or the unit that goes into the tank with the lines and level sensor less the pump. At $75.00 I would be surprised the unit contains the pump. Another thing to check is if this truck has the oval connector close to the front of the gas tank, check the ground wire in that connector as i have seen poor connections there.

 

Thanks burhead1 for the info. I will take a look at the ground wire as you suggest.

Here is a photo of the unit that I used.

Harley

 

That is a good price if includes all that.