Fuel gauge question

[dedwards777]

I have a 1999 bi-fuel contour. The last time I filled it up with CNG, it wouldn't start again. I assume my compuvalve is shot because I have been smelling the natural gas for some time. So for the time being I am just running it on reg gas.
I have the switch on the dash turn to reg gas mode and the car runs ok, but the gas gauge is stuck on full. I have since pulled the reg gas tank unit and tested it with an ohm meter and the sending unit appears to be working. So now I think my fuel gauge is reading the CNG tank and not the gas tank even though I an in reg gas mode. Could there be a stuck relay or something? Does the dreaded compuvalve also control the fuel gauge source? I wish I had a wiring diagram for this thing. Another thing, my car always seemed to run with less power in CNG mode vs reg gas mode, it is running like I am in CNG mode.

[fach]

Re: Fuel gauge question

I have the exact same problem. It also appears we are not alone. I have done alot of searching and it seems this is a common problem. I find it hard to believe that no one has any type of diagram, or has come up with some type of solution. At least to make the fuel gauge work on regular gas.

I know I'm not answering your questions. I'm hoping that someone will see the string and give a reply to help us. I'm guessing alot of people, with the same issue, will also be appreciative as well.

[dedwards777]

Re: Fuel gauge question

I might be getting close. I started checking all the wire plug connections under the hood around the master cylinder. There must be a dozen or so wire connections. I unplugged each one and sprayed contact cleaner before putting them back together. My gas gauge seems to be working now. So now I am thinking it might be a faulty/dirty connection somewhere. I hope I fixed it for good, but I have my doubts. I would sure love to have my gas gauge working again.

[Vaselv4evr]

Re: Fuel gauge question

Hello everyone,

I also have a fuel gauge question, tho it's unrelated to this question. I have a 1996 Contour bi-fuel, but there is no CNG gauge.

Currently, I reset my odometer, drive about 100 miles, then go get more gas. It would be really nice to have an actual gauge. Does anyone know how I go about doing this in Utah?

Thanks.

[dedwards777]

Re: Fuel gauge question

My gas gauge is still not working on my Contour. Does anyone know the function of the electrical module that is located on the drivers shock tower?
This is the one with the two fuses and what looks like two solenoids on it.
I suspect that this is what is causing my car to still read the CNG tank even though I am running in reg gas mode. Any help would be greatly appreciated.

[harob1]

Re: Fuel gauge question

Hello everyone,

I also have a fuel gauge question, tho it's unrelated to this question. I have a 1996 Contour bi-fuel, but there is no CNG gauge.

Currently, I reset my odometer, drive about 100 miles, then go get more gas. It would be really nice to have an actual gauge. Does anyone know how I go about doing this in Utah?

Thanks.

Hi I just bought a CNG Contour, not working on CNG of course. My fuel gauge didn't work either on gasoline but drove it across country just watching milage. After home, I located fuel sender under back seat. Go get a Manual for these cars even though CNG won't be in it. Anyway I found the fuel sender is plugged into the CNG system. If you want to just by pass and rely on original wiring. Unplug and use the violet orange, white red, black, some of these are striped. There are more of course but your on the right track when you see that plug. Be carefull of the spring clip I lost one already. After seeing it is the original wiring I plugged that back into sender and just left the CNG plugs alone, Hey my fuel gauge started working. Drove about 180 miles and tank gauge read about 1/4 maybe a bit more. Filled up and it reads full. I'm in the process of learning the system and the wiring. Today I messed with the system and got gauge working on the CNG side. It was no power (12 volt) Hope this helps rgds. Harry

[dedwards777]

Re: Fuel gauge question

Hi I just bought a CNG Contour, not working on CNG of course. My fuel gauge didn't work either on gasoline but drove it across country just watching milage. After home, I located fuel sender under back seat. Go get a Manual for these cars even though CNG won't be in it. Anyway I found the fuel sender is plugged into the CNG system. If you want to just by pass and rely on original wiring. Unplug and use the violet orange, white red, black, some of these are striped. There are more of course but your on the right track when you see that plug. Be carefull of the spring clip I lost one already. After seeing it is the original wiring I plugged that back into sender and just left the CNG plugs alone, Hey my fuel gauge started working. Drove about 180 miles and tank gauge read about 1/4 maybe a bit more. Filled up and it reads full. I'm in the process of learning the system and the wiring. Today I messed with the system and got gauge working on the CNG side. It was no power (12 volt) Hope this helps rgds. Harry

Harry, THANK YOU! This problem has been a constant irritation to me. I did your suggestion and it only took 10 minutes and now its fixed. I was looking there before and never noticed that I could just change the plugs back there. Now I think I will see about removing the tank to get some needed trunk space back. THanks again!!!!!

[harob1]

Re: Fuel gauge question

Hey your welcome, A couple of days ago I got my Contour to fire up and run on CNG. I'm not saying I'm an expert, but I'm a Merchant Marine Chief Engineer. Even though I realize the Countour GFI system isn't the best I believed I could make it work. I have to work miracles on our ships too. RGDS.
Harry

[dedwards777]

Re: Fuel gauge question

Hi Harry, I sent you a private message. thanks

[jackblack]

Re: Fuel gauge question

Harry, I'm getting no 12v there also, where was the 12v problem at? I've check all the fuses, thanks,

[cnghal]

Re: Fuel gauge question

All,
Be sure to check this site's File Library:

http://cngchat.com/forum/forumdisplay.php?f=28

Larrycng has uploaded a lot of Ford and GFI manuals and schematics.

If it helps, be sure to send Larry a thank you.

[harob1]

Re: Fuel gauge question

Jackblack, To answer your question about power. I traced wires from fuel selector gauge out to engine compartment. Yes I found the relay board with fuses but still no power. While tracing more wires trying to figure where did power source originate, I lucked into a yellow wire that had a ring connector and was neatly tucked along the left wheel well. Making sure that yellow wire was at least + side of fuse ( it was ) I figured it didn't matter where 12 V came from as long as it wasn't reverse polarity. I still have no idea where GFI may have tapped into because of the ring connector, but the system began to come alive and work after just hooking up to + side of battery. I would assume you have checked the two fuses on the relay board. I believe GFI may of had another relay which was removed on my Contour. I would have just tapped into ingition switch and power down CNG side when you shut engine off. God I'd just love to see a real schematic of this thing. I'm not able to tell you much else at this time as I'm on my ship, and will be here for 6 weeks yet. If you luck out and find power source please tell me. I'm wanting to learn this system, I'm sure I can make it work. Last time I played with it, it ran on CNG but then I'd get check engine light. Would clear back on gasoline. OK Bud hope this helped. Harry

[fracman_okc]

Re: Fuel gauge question

Hey your welcome, A couple of days ago I got my Contour to fire up and run on CNG. I'm not saying I'm an expert, but I'm a Merchant Marine Chief Engineer. Even though I realize the Countour GFI system isn't the best I believed I could make it work. I have to work miracles on our ships too. RGDS.
Harry

Harry, if you could document this stuff and post or offer emails you would be a saint!

Chris.

[bobp118]

Re: Fuel gauge question

Thanks for the info it has helped. I disconected the plug by the fuel pump and the gas gage worked with no problem. My problem now is I keep blowing the 3 amp fuse in the relay. My understanding is that its backfeed protection. I unpluged all the conectors by the relay put in a new fuse and pluged them in 1 at a time checking the fuse each time to see if it would blow. I got to the last one j26 and that one did the trick. Any sugestions or direction would be greatly appreaceated.
Thanks Bob

[bobp118]

Re: Fuel gauge question

Just a secound thought the ford manuel shows a dash reset relay k326 and I don't have a clue as to where it is. This system seems to be a mystery.
Thanks bob