psycheus

Hi All,

This is sort of a stupid question but I just picked up a 89 TII and I've been driving it for about 2 week now and it's seems that I'm only getting maybe 12 mpg. Does that sound right?

Thanks,

Rick
rtm@frys.com

BlackRx7

I get 15 mpg in mine

psycheus

Really. Hmm.. I thought that the TII's where alittle worse for fuel economy. Does anyone know?

Porcupine

iTrader: (1)

I get about 17 - 19 in the city, but I have a '90 non-turbo. Although, I do drive it like it wants to be driven, fast... ;o)

I would expect a Turbo II to get worse mileage... but 12 seems a bit too low...

I would start checking the basic stuff:

Air Cleaner
Spark Plugs/Wires
O2 Sensor


If all those look fine... message me and I will have more suggestions.

-Mike

psycheus

Hey thanks a lot. I'll take a look when I get a chance hopefully this weekend, I've just been working so damn much.

Air cleaner -=- going to check
Spark Wires -=- going to check
O2 Sensor ? Wait where is this located? I just had it up on a rack an I think I saw it right after the Cat? Is that right?

Thanks!

Scott 89t2

I think I get about 15 in my 89tII. (I get 350Km on 55L) I figured it out once but I forget...

just do a full tune up. change air filter, spark plugs and wires, oil and filter change, fuel filter, check the timming and TPS, drain and flush the coolant and add a new MAZDA thermostat, new o2 sensor. what octane are you running? I'm using 94 now and I found I am getting abit more then with 92.

Flamin' NOS

You just got it 2 weeks ago? I'm gonna guess that you're getting into boost a LOT. When I drive my car sanely, I get around 15-16... but the rest of the time when I'm racing a lot, cruising on the highway at 130, that sort of stuff, I average around 12. It just depends on how friendly you are with the boost.

psycheus

Actually I just got a oil change (filter/oil), I just put a new radiator in (+new thermo and coolant). Do the 02 sensors improve gas mileage? I know that I need to change the fuel and air filters.

Does anyone know where the fuel filter is? I just got this car and am not all that firmilar with it. A... does anyone know how to change it? I'm not firmilar with these setups. Thanks!

psycheus

A.. well ya. I guess I have been putting my foot into it (most of the time). It's the boost that dramatically lowers the gas milege? Hmm... I guess that make sense.

Henrik

If u rev above 3600rpm the ECU will go open loop regardless of whether you're cruising or not and you get a big change in fuel consumption. This is at about 80mph in 5th on my 87TII. I get about 18mpg in combined city/highway and that's not babying it.

Henrik
87TII

RedRacinTII

I have an 87 TII, and I only get about 13 mpg.But I usually only do street driving, which really hurts the milage.A new O2 sensor does quite a bit for milage, but I don't know that it will help you.I have a new bosch one, and still get 13.You should maybe be seeing a bit better milage, but don't expect to pull much more out of it.

psycheus

Thanks everyone for their responses. How does a O2 Sensor help for gas mileage? It's just sensor, right? Maybe there is something that I'm confused about?

psycheus

I have calculated this tank of gas;

220 miles on 16 gal (I was broke so I let I go down to empty).

13.75 MPG on a 89 TII. This was with 87 octane. Now I'm trying 91. There's 88.5 (instead of 89) also.

Results to come.

ryan_69_s

Mine 87T2 gets 16 mpg.

felixblack1

the oxygen sensor measures the air fuel ratio. the sensor is only used by the computer when you are cruising at a constant speed/throttle. the computer then leans fuel accordingly. this is called closed loop mode. closed loop mode is automatically turned off once throttle position, speed... changes.

i heard the latter Haltech's have closed loop mode, is this true? if so what sort of millage do you get on highways (especially if u have upped boost, bigger turbo...)?

FELIX