Fuel gage acting up.
 

Ive got to get my car smogged here pretty soon so Im starting my pre smog workout.As instructed I put a bottle of CRC 05063 fuel cleaner in a full tank of gas and now the gas gage doesnt seem to be working right,wont move below 3/4 tank.I dont drive the car much,maybe twice a month around town.Is my sending unit dying?

Re: Fuel gage acting up.
 

Common C4 problem. Make sure you set your trip odometer

Re: Fuel gage acting up.
 

I have been asked to help someone diagnose the same exact issue. So is it a dead sender, or a sticky mechanism that can be worked with and cleaned.

Re: Fuel gage acting up.
 

Normally its a combination. The unit tends to hang when when the car is not driven and tends to seize into the postion. Many C4 owners have been stranded that simply have run out of fuel on a "FULL" tank. By then the fuel pumps (remember we have two) are normally fried as well. I always suggest you set your trip odometer on your car for this reason. If you all of a sudden start getting pnenominal Gas mileage you will know something is up. It's a well documented C4ism dont forget fellers just like their owners these cars are getting long in the tooth.

Re: Fuel gage acting up.
 

I recently had the same problem and found a thread on CF that was very helpful. Search for "Fuel Gauge Sending Unit Repair Tech Article" by Frizlefrak in the C4 section. It has instructions and even photos of exactly how to fix it. The only difference is that we have 2 pumps. It was a bit tricky to get the assembly out but with a little patience, it will come out.
I went step by step and it worked like a charm. I still reset the trip-odometer but the gauge is working fine now.

Re: Fuel gage acting up.
 

Had the same issue with mine, Jeff, albeit after I hit a curb. Problem was with the metering assy in the tank; it was hung up on the mounting bracket as others have noted can happen. Easy fix once you get it out of the tank.

Re: Fuel gage acting up.
 

O.K. heres the deal,Im loosing my mind our Im just plain stupid.As stated I put a full tank of gas in the car with some system cleaner before I get the car smogged.I drive my car a few times a month or whenever I get the itch but Ive been driving abit more to run this tank of gas out.It had been a week since I last drove the car but I knew this tank of gas was just about out but noticed the gage was at 3/4 a tank but had 190 miles on the ODO,I always reset the ODO with a tank of gas.I figure this tank is low at 190 so I go fill the tank and it only takes 5 gallons,5 gallons out of a full tank would be about 3/4 full.Sooooooooooooo,at some point I filled the tank with fresh gas and forgot to reset the ODO,and I dont remember doing it.At least thats all I can think of as to what might have been the problem.

Re: Fuel gage acting up.
 

You're not going crazy.....it's all in your head.....

I've done that before. I've noticed my ZR1 stays "full" for about 100 miles, then starts dropping rapidly. The '96s I have/had would stay on full for only about 60 miles before dropping, but not as rapidly as the ZR1s gauge shows.

Re: Fuel gage acting up.
 

The thread mentioned above covers how to disassemble and clean the contact and windings of the sending unit which could be the cause of your problem. Mine seemed to get worse and more frequent erroneous readings over time. It took about an hour and sure beats $300-$400 for a new assembly.

Re: Fuel gage acting up.
 

You know this may be worth a shot. The C5 gas gauge was finicky at times, and would stop working. Techron added to the fuel corrected the problem.

You know that ethanol gas is the culprit!