My car was getting 20-24 miles per gallon before I moved out west. 4-5 months ago I changed my timing belt and O2 sensor. Around that same time my gas level gauge empty light started not coming on. I ran out of gas in Montana because I was only getting 12-14 mpg and wasn't expecting it.

 

I purchased a Bosch O2 sensor from Autozone, probably a universal.

 

The car passed Oregon emissions right away...

 

When I start the car in the mornings the exhaust is very rich and cloudy, smells of gas.

 

Also, when I plug in the green OBD1 connectors it makes a beeping buzzing noise and doesn't read out any codes.

 

Any help would be mucho appreciated as always!

 

If I was to get a Voltometer and try to test out the O2 sensor and the engine coolant temp sensor, how do I do that?

Let's start with the basic, when was the air filter last replaced?

Do you still have the old oxygen sensor? Put it back! You might as well just change the coolant sensor as it isn't expensive and ya check your air filter!

My car was getting 20-24 miles per gallon before I moved out west. 4-5 months ago I changed my timing belt and O2 sensor.

 

Doe it run and idle correctly??? Perhaps you have one cam slightly off??

Doe it run and idle correctly??? Perhaps you have one cam slightly off??

 

Thats what i am thinking.

 

nipper

If I was to get a Voltometer and try to test out the O2 sensor and the engine coolant temp sensor, how do I do that?

 

You can't test an O2 sensor with a DVM (unless you have one of those Fluke portable O-Scope ones ). The CTS is really just an RTD (resistive temperature device - probably a thermistor), and will give a resistance based on the temp it sees. As long as it changes from low resistance to high resistance as the engine warms up, it's likely ok.

 

I also vote for valve timing. It's very easy to accidentally get the cam sprockets off by a tooth.

 

GD

I changed the t-belt 4 months ago, drove 4000 mile road trip. put another 2000 miles here in portland. water pump went out. had to disassemble the t-belt assembly to replace the pump. when I took apart i didn't notice the tooth off. when I put back together I was extra sure that it was aligned. Its not idling funny or running rough.

 

I think I threw away the old O2 sensor. I'll go buy an OE one.

 

I replaced the coolant sensor about 2 years ago. I'll check the air filter.

 

Thanks!

Dumb Question, you did unplug the green diagnostic connectors didnt you?

 

nipper

Even dumber question, are you calculating the mileage correctly?

 

ie. starting from a full tank, driving for a while, filling it full and dividing the number of miles driven since you first filled up by the number of gallons you put in?

Around that same time my gas level gauge empty light started not coming on. I ran out of gas in Montana because I was only getting 12-14 mpg and wasn't expecting it.

 

 

Perhaps your gauge is gummy and not reading correctly. Maybe try running some cleaner for a tank or two and see if it helps. Of course, if you're calculating your mileage correctly, this doesn't help much. But I thought I'd throw it out there.

 

Good Luck!

 

Will-

Let's start with the basic, when was the air filter last replaced?

 

Air Filter was replaced 10K ago. Its still very clean, just checked it.

My 96 obs 2.2L has been getting 14 MPG since I've owned it (about 500 miles total). The engine runs and idles great!

 

I hope you figure your issue out so I can learn from you.

 

So far, I've replaced my air filter & PCV with no difference in MPG.