Excessive gas usage...HELP - Page 2

Rivals Inc · 07-03-2008, 12:27 AM

ok, the sensor i replaced has 2 wires to it, and the temperature of the car usally runs hot. i noticed theres a leak in the coolant jug at the bottom, so i have to put in water everyday, not to mention theres hardly any air getting to the engine since my intake gathers hot air from the hot engine. And the fan works, i got it hot wired so i can turn it on myself. perhaps i need to changed my spark plugs i bought, i did get champions iridium spark plugs. perhaps a full tune up list is good. i'm also trying to find a turbo vent or a small WRX style hood scoop to put in front of my intake so it'll gather cooler air.

RC1488 · 07-03-2008, 11:20 AM

Good you replaced the right sensor.
Car running hot-Could explain your bad gasmileage.
Get rid of those iridium spark plugs!! NGK Copper is the BEST plugfor the s-series.

I will post a full tune up list in the How-to Section

Rivals Inc · 07-03-2008, 05:09 PM

ok so maby? if i find the right hood scoop, that should help out with the heating problem which in turn should help out the gas problem. and i will get the NGK copper, should have in the first place. thanx for the list

RC1488 · 07-04-2008, 04:13 AM

A different hood may or may not help. As i said you car should be at 1/2 as per the gauge. With a '92 = over 10 years old, it may be the radiator is clogged. Typically the radiators go around 10 years old. At least thats the trend for most s-series owners. Also, water should be 1/2 of the fluid in the system. The other half should be antifreeze. Its important to keep this balance as best as possible.

As a side note, a bad thermostat always fails in the open position. Meaning it allows fluid to run into the radiator and cool the car down. So since you issue is the opposite i would think the thermostat is alright.

Where is the needle in the temperature gauge when you are driving on the highway?

Rivals Inc · 07-04-2008, 04:32 AM

1/2 to 3/4 per the gauge. the radiator was replaced 3 years ago. now i can turn the fan on and have the heat full blast (to let the hot air out from the engine), it'll run at 1/2 per the gauge. but my gosh its hot enough as it is even with the windows down. now stop light to stop light, around town, its at 3/4 to the red per the gauge.

96sc2 · 07-05-2008, 12:28 AM

Are there any codes? How long has it been since the o2 sensors have been replaced? EGR could be an issue, but you could feel that in idling, and performance. Do you have a way to monitor the sensor values? If you did you might see something there.

In my service manuals some suggestions are
tcc lockup (not locking up)- I've seen this before
cruise control cable adjust
induction clog
air temperature sensor
ignition system
fuel pressure
coolant tempperature
vacuum leaks
knock sensor

The list isn't short and it shows the many variables involved. I also have a 96sc2. It has a manual transmission.

Rivals Inc · 07-05-2008, 03:11 AM

i don't know- tcc lockup (not locking up)- I've seen this before
i don't know- cruise control cable adjust
what is this?- induction clog
highly doubt this-air temperature sensor
maby- ignition system
its good, trust me-fuel pressure
brand new so thats good coolant tempperature
no vacuum leaks
i'll look it up knock sensor

and the o2 sensor was replaced 3 years ago when the radiator was replaced.

96sc2 · 07-06-2008, 12:11 AM

Do you have an automatic? If you do, this one should be fairly easy to identify. On my lockup transmissions, I can usually feel when it enages - or not.
The induction clog(service manual words) would be anything in the intake air path.
I don't know the procedure for adjusting the cruise control cable, but could get it easy enough from the manuals if you're interested. It would likely be a good idea to test it first - probably also in the manual.
Unless you've measured the fuel pressure I'd still consider it a possibility.
Vacuum leaks are found by spraying carb cleaner around hoses and gasket surfaces.
There isn't a way to adjust the timing, but with a timing light you could see if it's at the least working by adjusting engine speed and wathcing for changes in pully position.
There is more than one o2 sensor. Can you smell richness in the in the exhaust?
Just thinking out loud on this one, but I wonder about some fuel treatment that cleans injectors?
For the air temperature, seeing a measurement of it would be valuable.
To make measurements test equipment is pretty reasonable. I use OBDPro. It's an interface that connects between a pocket pc, and the diagnostic connector -about 80 bucks, and the software is free.
You didn't say anything about codes yet. I believe there can be some that don't set the ses light. Auto zone and checker can both check for them and the there is no charge.

96sc2 · 07-07-2008, 12:40 AM

Just a little follow up. I know that the 92 sc2 is an obdi system. My 96 is obdii. But there still should be a lot of common things to measure and look at while troubleshooting.

RC1488 · 07-07-2008, 03:26 AM

Your operating temperature should be 1/2 as per the guage. The fan will NOT turn on untill 1mm before redline. YES this is very odd and hard to adjust to but its NORMAL. In '96 they re-adjusted the calibration on the gauge bc many were thinking the engine was over heating when it really wasnt at all.

A fuel injector cleaning could help. Again 10 years is usually around the time when many do it. I have heard good things about this place WitchHunter Performance - Injector Cleaning & Flow Testing Services
They even give you data of before and after to ensure you got your moneys worth. It couldnt hurt at all