My 95 SSEi has been getting terrible gas mileage lately. I read one of the posts latetly discussiing Torque Converter lockup. It was mentioned improper lockup will lead to bad gas mileage. It then hit me that I have been getting **** poor gas-mileage since the tranny was rebuilt.

Since I do mainly city driving, is it ok to drive in 3rd instead of overdirive? When I say is it OK I mean will it hurt anything over a long period of time?

Thanks.

P.*. It is a 95 so getting a scantool on it isn't an option.

There are scantools for the 95. Jrs3800 has one actron so he can tell you what to get if you're intersted.

Under 40 MPH they are the same shifting program. You can push it between them and never notice is. You may need a tune up, or a lighter foot

Hows the ATF look on the dipstick?

I have the same Actron. If I had the 16 pin cable, it would read your car just fine.

If you suspect your TC isn't locking up, tell us if your RPM'* drop slightly above 48mph. How many RPM'* do you run at 55mph?

If you don't know how old your O2 sensor is, or if it'* over 50k miles, it might be a good idea to change it anyway. It'* getting tired. Too many factors here. Do you run premium fuel? When was your last tuneup, including plugs and wires? What'* the general condition? Power? Performance?

Thanks for the response.

I will check the rpms on my way back home and post the results.

I just replaced the ignition module, the plugs, the O2, and the air filter.

The plug wire are about 2 yrs old.

I usually run just regular. But I did try Premium for three weeks and got better results, but not enough to cover the extra cost.

Car runs great and pulls when I get on it.

I have yet to run my can of Sea-Foam yet.

Only thing else is either fuel filter/regulator, or just that the car is old and tired.

Thanks.

Those little labels on your car that say "Premium Unleaded Fuel ONLY" aren't just a guide. It'* a requirement. You will damage your engine over time if the timing can't retard enought to prevent knock/detonation.

Your fuel mileage is crappy at least in part because you're running the wrong fuel. Don't EVER run lower than 91 octane except in an absolute emergency.

Run premium for awhile. Your engine is probably all carboned up now. Use some top-end cleaner, run 91 or better, THEN recalculate your mileage.

I usually drive in 3rd in stop and go city driving.. the only time I would shift out of 3rd to OD is when I know I will be able to do 80kmh for a bit.. I find since I"m */C And I stare @ the boost gauge more then the tach that when I"m in city going from 70kmh up.. I tend to have to hit higher boost.. picks up speed slower and heavier on the foot.. thats why I started leaving it in 3rd.. the only thing I don't like bout my car is that there'* no quick reference on the dash like they do on 00+ so you know.. oh crap.. I"m doing 110kmh in 3rd gear.. not good

Don't consider ANYTHING transmission related until you start running 91 octane every day, and use some form of top-end cleaner to undo the buildup you've got so far.

How long have you been running low-grade?

Willwren: I hear you loud and clear. Just came back from checking my car downstairs, and the Fuel Door has a placard which states to use unleaded fuel only, and "suggests" premium. Tha'* probably why I switched from Premium to Regular way back when.

I will start tonight and see if it improves.

Thanks.

Switching now won't solve your problems. Try some GM top end cleaner. Here'* a link to our first use of it:

http://www.bonnevilleclub.com/forum/...ic.php?t=17556

You probably have alot of buildup in there, and you need to get rid of it.

Just wanted to update you guys.

I did a SeaFoam cleaning this past weekend. Puffed out some smoke but not a lot. I also just finished my first full tank of Premium unleaded.

I did see a pretty big improvement in driveablility. She now pulls pretty good. Will wait till the third or fourth fillup to see if there is an improvement in mileage.

WIll keep you guys posted and thanks for the help.