flashing check engine light

[bhearts]

Hey guys. I have a96 aspire. I've been running it with neither o2 sensor for over a year which is why my check engine light gas been on. But just yesterday it started flashing. I've driven it 30 miles while flashing with no funny smells or sounds. What could have caused it.

[TominMO]

Don't know why it's flashing, but consider this: by not having good Nippondenso O2 sensors in there, you are running in "limp-home" mode (very rich), which means you're using a lot more gas. It would be much cheaper to install the sensors.

[FestYboy]

flashing light indicates cat damage (likely from running rich because there's no o2 feedback to the ECU).

get at LEAST the front o2 sensor in that car NOW.

[koRnhead]

Yup.....what did you hope to gain by not running ANY o2 sensor? If a crappy one is better than none.

[rmoltis]

That's too funny.

The o2 sensor up front meters the air fuel ratio.

And the rear o2 measures the exhaust gas after the catalytic converter.

You might as well just replace both of them.

I paid $50 for my downstream sensor.
And $35 for my upstream sensor.
Both online.

And the best thing is.
You just unscrew both o2 sensors
And they just unplug from the harness.
Then you screw each one back in
and plug them back in.

It would probably take 15 mins to replace both of them.
And it would ensure a longer engine life.
Along with reduced fuel costs.

[bhearts]

My exhaust is all home made. I guess I'll need to put a couple bung holes in

[jbibb1]

It's only a "simple screw in" if your not in the "rust belt" or you used anti seize - which most people don't use -it's usually a much bigger deal than that

[rmoltis]

I live in the rust belt...
When I took my old downstream out it wouldn't move by hand or by foot.
So I hung a crescent wrench on the nut and took my sledgehammer
and smacked the wrench and it came loose first try.
It made me smile to use my sledgehammer working on my car :-)

[FestYboy]

My exhaust is all home made. I guess I'll need to put a couple bung holes in

yup.

[MasterTec]

Flashing indicates a failure which could cause damage to the Catalytic Converter if it is continued to be driven.

This is almost always due to a misfire.

[TominMO]

My exhaust is all home made. I guess I'll need to put a couple bung holes in

Is your exhaust manifold homemade? That's where the upstream O2 sensor is. The more important one.