636jesse

I took my stock 06 A6 in for the headlight recall and asked then to do the smog test since it is due. My car failed because of the dreaded service fuel system light being on right tank sender. I guess in CA they check for codes when doing a smog. Any suggestions on how to get it to pass without paying the 2k to fix the sender. My car has a little over 100k on is so GM is no help. Seems like a known issue will make my car unable to be registered with out a big repair bill.

RocketDawg

Many have had success by running a couple of bottles of Techron through the system. It might free something up that's stuck. It's certainly worth a try if you have time before your current smog cert expires.

EVRose

Dump a bottle of Techron in the tank and see if that helps.

636jesse

I have tried 5-6 bottles and always good gas. The service fuel system light has been happening for a year or so. I can live with no gas gauge just can't drive it without smog certificate. I have about 30 days till it's due.

RocketDawg

Techron is the only solution I've seen discussed on here. Could be you just have a failed sending unit and it'll need to be replaced. But it doesn't make sense that it would cause a failed smog test ... California has some weird laws.

russ472

if you have your car tuned, your tuner can tell the ECM to not set a code if they are failing.
I did that to mine because I got sick of the service fuel system warning coming on. after I turned it off, the gauge started reading again.

Bruze

Ha! Interesting.

I'll have to put this in the ol' memory hole in case I ever have this problem.

Eritosthenes

I had the same sensor failure at about 60K. I turned that lemon into lemonade by taking advantage of the major disassembly to also replace my original fuel pumps with Z06 counterparts. Later that summer this swapout allowed me to choose the 600bhp Edlebrock E-Force model 1593 supercharger.

VET4LES

I'd take it to a smog check station. I've never heard of a gas gauge causing it to fail. Find a pass or don't pay station. Keep us posted.

C6ToGo

Might try my solution.

https://www.corvetteforum.com/forums...68-issues.html

Easy to get to the right tank sender wires through the wheel well. You cut the sender wires and wire in a fixed resistor with the ohm resistance needed to fool the car.

CadVette

The suggestions offered by others are good ones. However you may want to eventually replace both units on the tanks as there is an internal gas filter inside also. It's only a matter of time before the other side goes out too.

636jesse

I was going to try a test only station just to see if it will pass. When I told the service writer I would replace both if I do one he looked at me like I was crazy and said no one has ever done that. I guess they want to do the job twice. I didn't think you could tune that sender off on a 06 just the 05. Can I do it with a tuner I can buy or should I find a local vette tuner and have it done?

gaphono

Assuming that the fuel guage is working at some level of gas in the tank. I would use a Code Reader to clear the code, ride 50 miles to allow the computer to contain some drive history, then visit for the smog test.
I this this and passed.

dryadsdad

Local indie tech says BG fuel conditioner / cleaner better than Techron. May as well try that as well as the other suggestions here. Beats $2k down the black hole.

636jesse

I will try the BG I have nothing to loose.

v26278

My thought exactly. Clear all codes, and, unless the code is triggered again in too short a time frame, get the test immediately. Odds are there's a window to take advantage of and at least pass the smog test and then decide what more you want to do if the techron doesn't work. If you're always using the same brand of gas, try switching for a while - that worked for me when this issue starting cropping up repeatedly for me.

C6topless

I have a little experience with this situation. If you reset your code, you need to drive your corvette for a while until all the monitors come back on and read Ready --- ( emission , fuel system ect ) .. if one is listed as not ready ... you will fail. You cannot just clear a code and go in for a test.

C6topless

will not work as the monitor systems will register NOT READY and this will trigger a fail.

v26278

Right you are, I stand corrected, and I see gaphono alludes to that in his post reccomending a 50 mile drive. If you clear any codes, then all OBD monitors associated with those codes must first run through their diagnostic test routines without the code re-triggering or you'll flunk the smog test. Fuel system monitors can be one trip or two trip monitors, so it might be a good idea to see if you can run at least two trips with ignition on and of without re-triggering any codes, and then try and pass the test.

636jesse

I notice that from a full tank once I have used a few gallons all the lights and warnings go out for a 100 miles or so. I'm going to experiment and see where the sweet spot for the gauge is then retest. I have never let the tank get real low since this started will the drivers side tank and sender read right?