My gas gauge in my blazer isn't wokring correctly, most of the time it will go from 1/4 tank and then to Empty and the low fuel light will come on in the matter of a minute. It is always just moving all over the place and I was wondering what do you think would be in my best interest to replace to solve the problem.


Thanks!

 

The Sending unit is bad (It's mounted inside the fuel tank along with the fuel pump)

 

The fuel level float is contained within the fuel tank. It is a simple device that as the level of fuel rises and falls a simple mechanical arm moves across a series of contacts which in turn relay that signal to the guage to indicate fuel level. It is fairly common for the fuel sending unit to fluctuate as the fuel sloshes around in the tank, although there are baffles in the tank to prevent fuel from just sloshing all over the place. Depending on how sensitive your fuel level sender is, your guage will reflect that sensitivity as you drive and the road level, driving conditions, etc change. I just replaced my fuel pump and have noticed that my fuel guage "moves" a lot more NOW, which indicates a fairly sensitive float/sending unit. Your conditions DO NOT sound abnormal. To alleviate the "problem" may involve keeping the tank more than 1/2 full most of the time. Also note, gasoline acts as the cooling fluid for the fuel pump, so keeping the pump cool (by keeping the tank 1/2 full) will lengthen the life of the pump.

 

Would the sending unit be hard to replace if I did it by myself with my Dad, and also how much does the sending until cost for a 2002 blazer?

 

Check the AC/Delco site for information on the sending unit, some years had seperate sending units. Dealerships now will only replace the sending unit with a new fuel pump. Kinda makes sense but isnot what I would do. Prices can vary so check online and instores...

 

Is it fairly easy to replace by yourself?

 

Not exactly, you can now buy a fuel level sensor at any Dealer and we change them seperately of the fuel pump all the time.
I think for a blazer they're around $100.00 but check with your vin to be sure.
I'd say no it's not the easiest job for a novice, It can be done, but you should have at least 2 people and one of them should have a thorough understanding of what's involved with removing a fuel tank. You want to run it almost completely out of gas before you start the job, and get the truck as high in the air as possible...just be very carefull not to break the fuel lines off of the fuel pump module (the white thing that houses the pump/sender) If you break that you'll be spending $500.00 + on a new one.

 

Lastcoupe is correct in both aspects. If you call the dealership, 9 times out of 10 they'll try to quote you the assemble (which is $500 something). Make sure that they know that you just want the sending unit portion. There is a part number for it, though I can't recall it right now, and www.gmpartsdirect.com sells it for about $75 instead of the $110 the dealership here wants for it.

Another tip is to drive the truck until there is only one or two gallons in the tank and then do the job. It'll be a lot lighter for you. For now, just drive by the tripmeter. I would try to only go about 200-225 miles on a full tank of gas. That should keep you from running out of gas until you get it fixed.