Contour Enthusiasts Group Archives Forums Branches W. Great Lakes Question for car tech guys

My car pings on 87 and 89 gas, but runs fine on 93. I tried using Gumout Regain fuel inj cleaner and still is the same.

If I use 93 all the time, will it wear out any sensors?

i dont think it should wear out the sensors... is there a way to bump the timing down on a contour?

I can't see why it would wear down any sensors. I think the only way you could bump the timing down is with a chip.

BTW Tom I like your sig "110 on I-94" I got mine up to about 130.

Fuel injector cleaners don't do much IMHO. I take it your car is still under warranty, so have them check the knock sensor. Perhaps a bad O2 sensor could cause this too?

i dont think bad o2s would cause a knock... the only thing i can think is the timing being off... but there arent any distributors in the contours

ALWAYS BURN PREMIUM FUEL

no you do not always burn premium if you do your car will run rich and that will burn up your plugs and give you bad milage tom you may have gotten some bad gas but your pcm is not mapped for premium so run what is recomended 87 unless you drive a svt or have a chip that dictates otherwise

Running premium is pointless unless the car needs it. The Duratec has a fairly high compression ratio so mid-grade might do some good. Otherwise, you are wasting your money.

:rolleyes: Premium will not burn up your plugs or make the car run rich or wreck anything in the car. It WILL make you faster by making your wallet lighter if you don't need it. That said, if you ping, use the lowest grade that you don't ping on until you fix the problem. Maybe an intake cleaning? It could be bad gas if it is a one time thing.

The non-SVT PCM is programmed for timing that can use 87 octane, so pinging is not normal. A chip advances timing, which is why they tell you to use higher octane. A chip is the only way to change timing (well, there are a few others but they are much more $$$).

Redline actually makes a good in-tank FI cleaner (unlike the rest which are junk). Try a bottle of that.

Checking the knock sensor won't fix the cause of the pinging.

A bad O2 could cause pinging if its leaning out the car, but by the time it does that you should have thrown a CEL.

Hope y'all don't mind my trolling, but I wanted to throw in some good advice to increase the sig/noise ratio in this thread.

Car is done, and I got it back now. Runs better!

The ECM needed to be reprogrammed. No bad sensors or anything.