cumminsram06

I've asked about my 93Z several times before and received great help from people here, so I've got a few more to throw out:

My car is awful thirsty, In a 45 mile round trip I use nearly a quarter tank of fuel, doesn't that sound a little high? Especially for an M6 and 75% highway miles? The car has 3.73 gears in it, and I am going to change back to the stock 3.23s very soon to try and help out my problem.

Also in the search for the problem I am going to be doing a full tune up just to eliminate any super simple causes. Plugs, wires, oil and filter, fuel filter, o2 sensors, and cleaning out the IAC. Anything else I should replace while I'm in there?

Lastly, how would I know if the car is running as efficiently as possible or even going into a closed loop? Is the easiest way just to get a data logger like the TTS version? I'm not looking for performance just yet, I want the car to run perfect in it's current condition before I start playing with it.

Thanks a lot

RamAir95TA

iTrader: (2)

I'd kill for 180 miles a tank!

Your best bet is to acquire some real-time datalogs via Datamaster. It's an invaluable diagnostic tool. Doing a tune-up on those things you mentioned is always a good start.

cumminsram06

My odometer/speedometer is so far out of whack from these gears that I don't have any idea what I'm getting for fuel mileage truely. So my first step will be getting rid of those to see how bad it really is. I just know my drive to work is about 45 miles from my previous vehicle and I can nearly watch the gauge move as I drive it. Just doesn't seem right.

RamAir95TA

iTrader: (2)

If you value performance, don't switch back to 3.23s, please!

bowtienut

iTrader: (1)

Don't waste your time swapping back to 3.23's thinking that will help your mileage. Gearing is not the issue.
Check for any exhaust leaks prior to the O2 sensors. Even a tiny leak can play havoc, causing the PCM to dump extra fuel to fix what it mistakes as a lean condition.

the_merv

iTrader: (88)

Ya gearing is def not the issue.. I have 3.50's in mine and I'm going to be puttin in my 3.90's to help my MPG..lol

Less bod on the Engine..

cumminsram06

I do smell gas at times when sitting at a stoplight at times, not raw gas but exhaust for sure and I always thought it was odd. Sounds like an excuse to get headers? I'll look into the exhuast and see if I can see anything. Thanks again!