I have a 95 LX. Since it was new, it has pinged in warm weather (say above 85 degrees F / 30 C). I put in higher octane gas, and that fixes the problem. Do other people see this same problem, or is there something wrong with my car?
Something´s wrong with your car man. LX´s were designed to run on the cheapest 87 octane you can find..."they´re economy cars." Anyhow, if getting your octane up solves the prob, its because higher octane fuel burns "slower," so to speak. I would check your timing. If when the air temp goes up the sensor misreads and your ECU over advances the timing...you would get the same problems your experiencing. Likewise, sounds like it might be time for a full tune up, and that includes plugs and wires. If your plugs are fouled they could be holding heat. **If your plugs actually look okay when you pull them, I would recommend going to a little colder plug until you can take the scort to a shop to have the ECU and sensors checked. The colder plugs will hold less heat and let you get back to saving your money on fuel.
Does the car "Diesel" at all?? Does it keep running for a few secs after you turn it off? I´m not sure if feul injected cars are prone to doing that, but when my Mustang had the v-6 I had to run atleast mid grade or it would ping and keep running after I turned it off. That is usually caused by carbon build up on the pistons and in the combustion chamber. It gets hotter than the flash point of the fuel and ignite the fuel instead of the spark plugs. So you might want to try running some top end cleaner through your engine as well. Like Blade said though, a tune up would deffinatly be in order also.
Oh also a tid bit about the heat ranges of a spark plug... If you do mostly long distance freeway commuting then it is ok to go a step colder on the plugs since your engine operates for a long time at it´s optimal temperature range. If you do mostly short trip grocery getter duty with your car you might step up a heat rane to alowy your plugs to clean them selves more efficiently. That is something one of my teachers once told me, but correct me if anyone has heard different. And another thing. If your running NOS, go colder. But most people don´t have that problem on here.
I can verify that one for you. Running plugs in they´re proper heat range can help clean them.
Also, not just oxidizing the fuel, but you should go colder when running forced induction, or even if you´re raising your compression ratio. When the compression ratio goes up in the cylinder you´ll be creating REALLY high heat temperatures. To prevent knock, and hopefully detonation, you´re going to want to combine higher octane fuel, timing retard and colder plugs (prayers help too
93´ Escort GT (Special SLO model)
Premium fuel doesn´t "burn slower" necessarily, it just has a higher flash point so that pinging or knocking doesn´t happen before the Piston hits TDC. In fact puting premium in your car may (not always) MAY help power output, but not by much.
My car does not diesel. It runs in the normal temp range(lower half) on the coolant temp gauge. I drive mostly long distances at moderate temperatures. The car just passed state emissions testing with flying colors. There are no other driveability problems.
I will have to check the heat range of the plugs. I don´t think the timing is adjustable in this car. I am wondering - as suggested by the Blade - if the computer reads a temp sensor and this affects the timing control. Do I need to replace a sensor?