I installed the GM stage 3 PCM last weekend.

The car runs awsome but something weird has happened.

My gas gauge works backwards.
When my tank is full it shows empty and works backwards from there untill it reaches full when i'm actually empty.

Any ideas? Weird.

 

that is really weird.. i've been running the stage 3 pcm for almost 8 months now and haven't had that problem. put the stock pcm back in and see what happens. i know the dealer had to do a lot of rewiring under the dash of my car because of frayed and crushed wires from the factory.

 

damn man that sucks. i had a similar problem when i had my car tuned. have the dealership reflash it.

 

I have done that. The stocker works fine. I don't mind it that much but it's just weird. Thanks man.

I don't know if that PCM can be reflashed. I know HPTuners can't read it. I don't know.
I can ask but they are going to wack me $90.00, stealerships. Thanks man.

 

Hey just curious...I was thinking of getting a stage 3 pcm...what other mods are you running with it?

 

if thats true...how far does the needle go down on empty? ive always been curious as to how low is TOO low. ive been ON the red mark but never below it...can you go below it?

 

You will get about 15 more miles below the red line and then your SOL.

-Mike

 

An easy one for once. Is your car an 07 (or possibly a late production date in 06). Towards the end of 06 and beginning of 07 GM switched the way there in tank fuel senders read. Both the old and new style senders read the same range except that do it backwards. One has 40 ohms as full, one has 40 ohms as empty.

Your ecu doesnt match your in tank fuel sender. Id go explain it to the dealer and they should warranty it for you. (even if your out of warrantly gm performance parts have a 1 year warrantly on them)

 

The car runs great with the PCM. I got mainly to control the 50 shot i'm installing the spring.

GM Stage III PCM w/Polished 2.9" Pulley
Polished Injen CAI/AEM DryFlow Filter
XTC Stainless Header
XTC Downpipe w/High Flow Cat
GM Performance Exhaust
Hurst Short Throw Shifter
NGK BKR7E Copper Plugs
Jegs Oil Catch Can
XTC 3-Gauge Pillar/Aeroforce Interceptor/AEM Wideband Gauges

You are the man. I think you are absolutely right. I have an 05 but I think this PCM is for a 06 or 07. That would explain it. I had no idea they did that. Of all things to change. lol

I'm going to have to talk to the dealership. Thank you.