Poor gas mileage.

[Chip Hutchinson]

Hi guys. My '97 with 85K on it gets 17 MPG on the same commute that my '96 used to get 21 MPG on. The car runs great and the CEL is not on. Does anyone have any suggestions on how to go about investigating a problem like this? Any help is appreciated.

Chip.

[SVX8588]

Check to make sure you don't have a sticky caliper. I got around 21 with mine until one of the calipers slowly started sticking. I watched the mileage drop to 17 over about 4 months before I realized what the problem was.

[Freeman]

I get nearly 14 MPG in my 92 pearly.. Its terrible.

[dcarrb]

Originally Posted by Chip Hutchinson

Hi guys. My '97 with 85K on it gets 17 MPG on the same commute that my '96 used to get 21 MPG on. The car runs great and the CEL is not on. Does anyone have any suggestions on how to go about investigating a problem like this? Any help is appreciated.

Chip.

Is torque converter lockup pretty much the same on both cars over the same route? All other factors being equal, that'll make a huge difference. Aside from that, the usual suspects: Tire condition and PSI, air filter condition, aging plug(s), wonky fuel injector, and so on.

In 100% commuter mode, I've found 17-19 MPG is about the best either of mine has to give.

dcb

[Chip Hutchinson]

Thanks for the help. It runs so well that I think I will check the calipers first.

Chip.

[Conn SVX]

I cosider 17 in town pretty good. Of course what you call in town and what call in town can be two different things ( 6 traffic lights a mile or down town NY city or a rural town in Kansas ) I shift 21 times going to work and it is just under 2 miles.

[flamestone]

Check the fuel delivery system too.

For example, if you've got a fuel pressure regulator on its way out (rubber diaphram perishing), it could be wasting fuel through that.

[Huskymaniac]

Originally Posted by flamestone

Check the fuel delivery system too.

For example, if you've got a fuel pressure regulator on its way out (rubber diaphram perishing), it could be wasting fuel through that.

Could that cause a lot of gurgling noises when the car is first started? How does one check the FPR?

[92snowmachine]

the gurgling (if it is coming from the back seat area) is probably just the fuel pump. if you pull the vacuum line off the pressure regulator then you should be able to tell if it is leaking. the line will be wet inside, apply vacuum with a clear hose to be certain. when the diaphragm ruptures it allows fuel to be sucked into the vacuum hose.

[jetboy]

I previously had a 1:1 KM/L but now have about 1.2L per 10km.

It's a sticky caliper (FR). Teh pads look very and clean there!

[Chip Hutchinson]

Thanks everyone.
The left front caliper was binding, and the right front caliper, while not binding, had a bad (frozen) piston. Now to see what my mileage rises to. BTW my commute is 12.5 Mi. It is ~2/3 Freeway. but for comparisons, my '96 got 20.5 to 21 MPG on that route. It had 213K, and I expect that from my '97 with 88K.

Chip.

[jetboy]

Ironically, I didn't have a caliper issue

Must be the bad bearings.

[Conn SVX]

I once had a collapsing brake hose . When you applied the brake it would expand and when you released the pedal it would slowly resease the caliper.

[jetboy]

Originally Posted by Conn SVX

I once had a collapsing brake hose . When you applied the brake it would expand and when you released the pedal it would slowly resease the caliper.

Oh yes I tried nudging Sicksubie for those

[david_12121]

mine has the same problem and does about 13-15 MPG
I'm pretty sure it has something to do with the spark plugs and the slightly warped brake rotors...gotta replace those
but when it was healthy i could get 22-23 highway MPG which is respectable...