possibly/probably pinging

[NC325iC]

ok, its hot as hell (95 today) here, when i give the car some throttle pretty much anywhere in the rev range i hear what sounds like pinging, but in my hopes that it isnt pinging i have theorized that it could possibly be a belt that is not on correct or a bearing or something in my AC compresser (which isnt working correctly anyway(might just need a recharge though))

so what does everyone think?
i guess i could just remove the belt and test it

[b*saint]

Turn off the a/c and drive it around under the same conditions as when it pings. Or remove the a/c belt within a reasonable amount of time and continue driving.

[egk2]

Your stroker is pinging, you running the highest octane fuel?
Stock ecu/chip?

[NC325iC]

i dont have ac on as it doesnt blow cold,
running a chip mark D cooked up i havent yet dynoed it to see if there are any lean spots that could be causing this, i still have idle problems which could be caused by vac leaks but for the life of me i cant find them.
running 93 octane... im not that stoopit

[Adrian_Visser]

my 84 eta has had a pinging problem ever since I ran seafoam through it. it only pings at 1875-2000 revs then its fine. weird eh?

[NC325iC]

ok im confused as hell now,
unless what i think to be the sound of pinging is incorrect.
ive had the windows up the past couple days due to rain and i hear it and it sounds like its coming from under the driverside of the dash, in the cabin. i hear the noise only when the engine is under load, if i just rev it(no matter throttle pos) i dont hear it, when i accelerate i hear it (as long as revs are above 2500) and then later down the line it stops.
im confused any insight would be great

[Adrian_Visser]

well if it only does it under heavy load then that points to pinging(detonation).

[porsche gt1]

Are you sure it is not the valves ticking? Could also be a bad injector clicking.

[Adrian_Visser]

too true. a loose rocker would sound similar id say. but an injector woouldnt be nearly as loud. hey did u get the etm gt1? i got gmail so i think i can send it to you now.

[NC325iC]

its not the valves, i recently checked them and they are witin spec, and they arent that loud

why would it sound like its on the drivers side inside the cabin

could it be sometihng with the heater core or somethin

[NC325iC]

i give up i guess its pinging, what do i do about it?, is there anything i can do without buying more stuff (i will buy stuff required to do it right but a quick fix would be nice)
should i see if Markd will reburn me a chip with tard timing

[bddog]

Only run Chevron premium.
I had an old volvo 644 that was a leaded gas car. I had to put octane booster every tank to keep it from pinging.

[NC325iC]

dont have chevron round here, we have shell bp exxon citgo, i think thats it
highest grade is 93, i havent ever put a drop of anything below that into this car

i will probly go get some booster and see if that helps

[matte30is]

Do m20's have knock sensors to adjust timing for the lower octane fuel?

[pdx 528e]

Do m20's have knock sensors to adjust timing for the lower octane fuel?

No, neither do M30s. The engines are too old and probably too loud for an OEM knock sensor to work.