I just got back from a short highway trip. 300 km round trip.
So I wanted to see what kind of mileage I would get cruising at 130 kph contantly after my new headers installed.
Averaged 23 mpg BUT......the fuel gauge is still on the full mark !!!!
Now that'* not bad mileage for the speeds I was driving and I kept remarking all the way to Nanaimo to my wife how good it was cause look the gauge hasn't even moved yet.
In fact even after 300 km it'* still on the full mark with a fuel range of 620 km.

Just before I got home, I stopped for a ferry ride and when I restarted it, the gauge needle went down to 2/3 then slowly crept back up to full. Real weird, like some ghost was filling up the fuel. :?
Has anyone had this problem? Sounds like the fuel level sending unit is on the fritz.
Damn! :( It should be covered by the warranty.....it better be!!!!

Thats some good economy given the cruising speed

I wouldnt worry about the fuel gauge so soon maybe its a one time occurance?

I know in my 97, that I've got to go over 200km before the needle even starts to drop down. Basically when it starts to move I'm on 1/2 a tank of gas. And I normally only get just over 400km per tank.

I was hoping that it would be a one time glich but I checked it today and it'* the same.
When I turn the ignition on the gauge does its sweep thing and then goes to 2/3 then slowly creeps back up to full. It was very accurate before yesterday.
It'* just disappointing that such a new vehicle would have a defective sender so soon.
I have had similar problems with GM fuel senders before.
I'll wait a week or so before bringing it in to the dealer for warranty replacement.

sorry to hear about this problem.. but THANK GOD! I'm not the only one with this problem! That'* how I ended up running out of gas, my gas gauge said I had 1/2 a tank, but I was really on empty.. Mine always reads accurately until I get to below 1/2 a tank, then it'll go back to full and stay there. It never reads correctly once my gas tank gets low. I'm really not sure what'* wrong with it. My best guess is teh sending unit too. Let me know if that fixes the problem. It seems to be very common!

Read my post for all the details:
http://www.bonnevilleclub.com/forum/...ic.php?t=16458

Brought it in to the dealer today.
They have a new fuel tank sending unit on order. Thankfully it'* covered under my extended warranty.
Probably one of the few things that will be covered now with all the mods I have.

My warranty ran out long ago but thank fully I have had no major problems since.
Your going to have to beef up the tranmission soon if you start making any more power

I really havent had any problems with warranty work although none of it has been engine or tranny related (thankfully). Mostly suspension and interior (heated seats, windows) work.

400 ???
I thought mine was bad gettin around 600km per tank and Tamara'* will get close to 700'*.. I think there'* something going on..

Yeah, I'm in the same boat as Merlin. Just filled up Tuesday and have 146 miles on the tank (90% highway at 75-80mph) and I am down to 1/4 tank. I don't know when the last tank was that I got over 21 mpg.
I babied it on a 400 mile trip two weekends ago and got 21.5mpg.
I wish there was a way to get more mpg out of it like I did on my 1994. When I got the car I was getting 28-29 freeway. Then I after the exhaust and intake, plugs, wires, etc.. I was typically getting 33-34 mpg. Hell that thing got 23-25mpg on a bad day. Best mpg in the 94 was 35.5 mpg. Best I ever got in the 1999 was 26.5 mpg and that was typical of the first few tanks right after I bought the car. Then all of the sudden it was down to 21-22 and lately it'* been down in the mid teens. And no I don;t always have my foot in it. I like to use the cruise control unless I'm in town and because of the way she hogs the gas I have found that I can consistantly 'grandma' away from a stop sign or light -not that it seems to be helping.
I think it'* time I change that TPS that I had gotten the code from the Autotap session at the GP meet mod day.


Another thing that I bet is to blame it the poor quality gas we are getting. Hell, two years ago we thought we were getting bad gas for insane prices. Now everyone is complaining about bad gas mileage and the ones to blame are just giving us poorer and poorer quality fuel and raising the price because we are using more. Now if the government would just release the special stuff they're holding back from us......