Information on Sending Units

[happydog500]

I need to replace my sending unit.

I understood there was two used in 97 Lesabre. I went to the Buick Dealer they told me only one was used. I told him they switched during the yer. He said no.

I went to the Chevrolet Dealer and they told me there was two that year, and mine was "AW2, "W/Out." (Without AW2).

When I look at parts, they list one as, "HEN" "HER" and one as, "CRD".

Which one is without AW2?

Also, I read on some posts where they put in a new sending unit, only to have it not work right. Some have made the gauge swing wild when they go around corners. I don't want to do this again (twice this year as I got a faulty Pump).

I don't want to spend a lot of money. Has anyone put in a few and can share experiences of how it worked, lasted, and what brand?

Thank you,
Chris.

[Smith1000]

I got one at the salvage yard for my 97. I remember the guy asked me if it was "HEN", or "HER", or something like that. The reference he had indicated there was more than one kind for that year. I believe I had to give him the VIN number to get it matched up.

The salvaged one I put in has been in there for a long time. I have not had a problem with the gauge swinging on corners. The signal is buffered by the computer so that it will not show slosh in the needle. I believe, if the computer was bypassed, the direct signal would show slosh and would move more dramatically on slopes, etc.

When I replaced mine, the aftermarkets were much more expensive, about $300. I have heard they are much more reasonable now. The salvaged unit came with a fuel pump and sending unit, it was kind of all one piece.

[happydog500]

I tried with Rockauto, but he didn't know, even with my VIN.

He was real helpful tho, he talked to the people at ACDelco, which said they could not tell which one.

He also called Spectra Premium, the only thing they could tell him was they are different ohms, get the wrong one and the pump would not work.

He also called Dorman, but they where not able to give anymore information then the other two.

I wonder if this is why GM is in so much trubble? I need a part, but can't even get the information to be able to buy it.

Chris.

[Smith1000]

The ohm range on mine is 0 to 240. A half a tank of gas is right at 120 ohms. Prior to this, GM had used something like 0 to 78 or 80 as the ohm range. You might try calling a salvage yard. They might be able to provide some information. The book requested the vin number and/ or the manufacture date (I think).

[nkmhockey]

I recently changed the fuel pump/sending unit in my 1997 Lesabre. I was able to determine the harness code from a GM dealer - using my VIN, over the phone, they were able to find that my car either had harness code HEN or harness code HER. They said that I would need to drop the tank and check, because HEN and HER refer to two different part numbers at the dealer (and two different prices, ironically).

But, since HEN and HER refer to the same aftermarket parts, I was able to confidently order the Spectra unit from RockAuto. I highly recommend ordering the sending unit/pump as a pair. If I remember, the pump runs around ~$90 and the pump w/sending unit runs around $115 - very worth it. It saves you from ruining the old sending unit float, breaking the fuel gauge. Plus the pump comes pre-attached to the sending unit which saves time during the installation.

I actually replaced just the pump about a year ago, but had numerous issues (stalling, inoperable fuel gauge). I found later that the in-tank filter screen had fallen off. The first pump was installed by a mechanic, second unit I installed myself.

If I remember correctly, my old sending unit ended up being an HER - the tag can only be seen by dropping the tank. Good luck on your search!

[happydog500]

Originally Posted by nkmhockey

I recently changed the fuel pump/sending unit in my 1997 Lesabre. I was able to determine the harness code from a GM dealer - using my VIN, over the phone, they were able to find that my car either had harness code HEN or harness code HER. They said that I would need to drop the tank and check, because HEN and HER refer to two different part numbers at the dealer (and two different prices, ironically).

But, since HEN and HER refer to the same aftermarket parts, I was able to confidently order the Spectra unit from RockAuto. I highly recommend ordering the sending unit/pump as a pair. If I remember, the pump runs around ~$90 and the pump w/sending unit runs around $115 - very worth it. It saves you from ruining the old sending unit float, breaking the fuel gauge. Plus the pump comes pre-attached to the sending unit which saves time during the installation.

I actually replaced just the pump about a year ago, but had numerous issues (stalling, inoperable fuel gauge). I found later that the in-tank filter screen had fallen off. The first pump was installed by a mechanic, second unit I installed myself.

If I remember correctly, my old sending unit ended up being an HER - the tag can only be seen by dropping the tank. Good luck on your search!

Thank you for your reply. Your right, I am afraid of getting the screen off the pump. I put the old filter on my new pump (only a year old), then thought since I had it out, I should replace it anyway. I took it off, the little post that holds it on, was scraped up pretty good. I touched it to get a bur off, it broke. Good thing they gave me a new one. The pump is brand new, so I was going to have to take the screen off the pump again.

Might be worth spending the extra $50. Wish I would of thought of this sooner, I just spent $100, just for a new pump.

My thinking leans towards a CRD. One thing I've found is CRD fits 96-97, where HEN, HER is 97-98. My car is an early 97, just don't know at what point in the year the swich happened.

I don't want to drop the tank, then after that, place the order. Have the stuff off sitting around till it comes in.

Wonder if I p.m.'ed you my VIN, you could call up that dealer and see what they say?

Chris.

[nkmhockey]

http://www.powerofbowser.com/index.htm

The dealer has a toll free number in the top right corner of the homepage - you can call them yourself. Just go through the menu to get to the GM Parts department.

Another reason I went with the HEN/HER - I figured that way I have a 2/3 chance of being correct instead of 1/3 for the CRD.

Depending on how hard it is to drop your tank - you could remove the straps and drop the tank enough to see the wiring harness. You should not have to remove anything - then just put it back together and order the correct parts. That is really the only way to be 100% sure.

I also considered ordering both units and sending the one I didn't need back - that is an extreme, but still an option.

[happydog500]

Back again.

I called up the parts from the link. He had no idea what one, "It doesn't tell me the difference, just what one it is."

I went to the Dealer in my town again, to see if I could get anymore details.
I do know the part number for mine is, #19179526.

Also, the guy said the only thing to tell the difference was one is, "GXP", and mine is, "Not GXP."
The way he explained didn't make seance from what I know. He said the two are for Supercharged, and not Supercharged.

My research shows one is 96-97, and one is, 97-98, switched in the 97 year. That does not allow for a non-supercharged and a supercharged.

The more times I take off the hose, the more likely I'll get another leak. I'm trying to do this without dropping the tank again. Then doing it over again when I get it.

Wouldn't you think GM would be able to tell me what one my car is? I can't believe it.

I've defended American Cars all my life. This is stupid.

Chris.

[Smith1000]

Before you drop the tank, you might first disconnect the wires to the current sending unit and tie a wire in between the sending unit wire on the new one and the wire to the computer. Move the sending unit through the full range of motion, from empty to full. Have someone watch the gauge (key on) to make sure the new one works like it should. This is what I did with the one I got at the salvage yard. Once you confirm that it works, then drop the tank to install it. You may need to ground the new unit to metal on the car. If it is the wrong one, you can then get the other one before you drop the tank.

[happydog500]

Thank you for all the replies.

I got underneath the car, to look at the connections (Wires go from the tank to a spot under the car where it has a place you can disconnect). I could see the tag, "CRD" at the connections point. No need to drop the tank, I can see the tag.

Very good that the tag was not on the top of the sending unit, but on the wires down from the tank.
I have to take back what I said about Buick or GM. They put the tag at the end of the wires so you don't have to pull the tank to find out.

Thank you,
Chris.