I think I have a bad sending unit in my 122s. When the fuel level gets down around 1/4 tank, the guage needle bounces around all over the place. Is there a way to fix this, or does the sending unit have to be replaced? Can you tell me where to get one?

Thanks,

Joe

Joe;

The 122 fuel gauge system has a very fast response time as it is NOT dampened out to average out readings (as on modern cars (even later Volvos with the infamous Voltage Stabilizers) where you typically have to wait a few minutes after filling the tank for the gauge needle to rise and the full tank to be accurately indicated...or totally electronic cars where you may even need to cycle the ignition for the computer to make a new interrogation of the fuel sender). This causes relatively fast float changes such as fuel sloshing on cornering to be indicated as a bouncing needle.

If your needle bounces consistent with sloshing fuel, no problem, but if your needle bounces even faster, it suggests an intermittent connection possibly caused by poor contact on the float wiper.

I actually use this information...occasionally, when I get really low on fuel, I may give the steering wheel a fast flick from side to side...if I see fuel needle bounce indicating slosh, I know I still have a bit left and I'm OK for the moment, but if there is NO bounce at all, I know I better refuel IMMEDIATELY (no offense intended, but women wouldn't understand, their fuel gauge never drops below 1/2...why is that?). Of course, this effect is also a function of the gauge adjustment, but I actually like mine adjusted like this.

Luckily, I've never gotten stopped for doing this trick in view of a police officer...I'd hate to try to explain my "erratic driving" as a "low fuel level check"...he'd probably have me doing a field sobriety check in about a millisecond.

Hope that helps.

Funny, I just did that "low level fuel check" last night. Actually fit 8 gallons in the tank (which is probably the most I've pumped in there)..what does that tank hold?

Per

Per;

Only 8 gallons? With a good tune-up giving you aroud 30mpg, I could have almost made it from here to NYC (100 miles)! You're not a "real man" until you've let your tank go down so far as to need almost the full 11 US gallons (I believe) it takes to refill!!!

[Running out however, is uncool and to be avoided!]

Cheers!

I'm getting at most about 26 with the Isky/IPD street perf. cam on the highway (5k rpm for many, many hours). 20 around town (driving like I do).

Per

http://www.grassrootsmotorsports.com

The guage is steady when the tank is full, but gets more mobile as the fuel level drops, consistent with fuel sloshing around in the tank. My old VW did the same thing. When the tank gets around 1/4 full, however, the needle bounces around erratically (full-empty-full-empty-1/2-empty-etc)even when the car is standing still (but it's worse when the fuel is sloshing).

I'll take the sending unit out this weekend and take a look at it. Hopefully, I just need to make the adjustment George suggested.

Thanks for the replies!

Joe

First thing to do is carefully take it out (NOT with a full tank!)

and look at the resistance wire where the finger contacts it.

It may be that the finger just needs bent to apply a little more

pressure to the resistance wire, assuming the wire is just worn

and not broken.

(Probably wouldn't work at all if the wire was broken.)