The gas mileage has been off for sometime.The mileage has been running around
22.5 MPG around town,which I think could be alot better.Today I changed the O2
and to my suprise which I've never seen before the O2 sensor was orangest red on the end.I used a meter on the O2 at every oil change to check the switching and everything look fine.I was wondering if anybody else has seen this before and what it was doing to there engine.The fresh O2 sensor seems to have help out already in throttle response and in idle.
Thanks for a reply
Rodney

Both Shell and Chevron use Techron as a cleaning agent in their fuel. This is probably the best additive that you can get to maintain a clean fuel system and combustion chamber. As to you using the higher grade of fuel, you should not need to worry about harming your engine. I occasionally run a tank of 93 through mine, and it seems to like it (a lot). I make do with 87 Chevron or Shell routinely, and recently when I pulled the intake manifold, the injectors, and the intake, all the way to the valves was clean as a whistle. I'm happy with the stuff. I have not a clue why you would have 190-195 pounds of compression, unless someone took a serious cut off the head, or crammed in an ultra high compression set of pistons.

Bill
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Those who beat their swords into plowshares, will surely plow for those who did not.

I couldn't stand the way the car was running and I went ahead and got the engine hot then did the cold water suction through the intake vacumn hose.I then did another compression test after running a pint of water through it.The compression went down to 145 to 150 PSI on the head. I think that now I will get better mileage.I know that the engine was spark knocking and that not good for the timing.
Thanks for the reply
Rodney

I did as I said I would do today,I pulled all the plugs on the engine,all the plugs had the same red tent to them as the O2 sensor had.I went ahead and cleaned the plugs and did a compression test on all the cylinders.This part I didn't like all cylinders had a compression of 190 to 195 PSI.The engine says that it is a B230F.I pulled another one of my 240's in the shop and checked one of the cylinders on it 150 PSI.Tomorrow I'm going to do a carbon cleaning on the top with water and check it again.I'm to the point that it's time to put this ported and polished head that I've been saving on the engine.I know now where the gas mileage is going.I should be using 93 fuel instead of 89. I'm alittle lost on this one.
Thanks for the replys
Rodney

The reddish staining of the O2 sensor tip is probably caused by fuel additives that are forced by the feds and lobbyists... in order to up the price of gas. If you pull the plugs, you will probably see a similar hue on them. In the early 90s, the "hue" was more "green/yellow".

jorrell
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92 245 250K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

I will pull the plugs tommorrow,I've been using shell 89
I wonder if this is hurting the engine
Rodney

The additives will not harm the engine, they just have a bad habit of depositing on the hottest parts of the system, ie. plugs, O2 sensor, and cat. Quite surprisingly, these deposits only seem to build up to the point where they discolor a surface, they don't seem to plug things up. After a million miles though, it might be an issue :)

jorrell
--
92 245 250K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!