Timing (how To?) ...i've Got Serious 'pinging', how to check / set timing? dunno what else it could be... Options

[blankenship]

I've got (2) '88 Mitsubishi Vans with the same stock 2.4L that came in the Eclipse.
I bought one of them last week (has 118k) , and it is doing some SERIOUS "Pinging" under load/acceleration, and also runs a bit rough at idle.
Plugs and wires are new, cap + rotor are new, air filter is new, etc...

Which makes me think there must be TIMING trouble...(unless you've got a better idea).

I've got a timing light and would like to check it, but am used to a different set-up, I guess, because I can't figure out how to do this.
I don't see any timing degree marks on the crank's 'harmonic balancer,' so how the heck am I supposed to tell?
Also, instructions I've found mention first grounding the "ignition timing adjusting connector," which I have no idea where or what that is...

Help or ideas would be appreciated.

[waynerwats]

did you try a higher grade of fuel?

[Az3g]

Bad timing will sound strange... but a ping comes from internal components. Id say you have a bad lifter or something in the valve train. Ive been jacking around with timing alot lately and all it will do is cause a change in your engine performance. if its retarded, it will putter especially at low rpm, and have crappy acceleration. If its advanced, (depending on how much) it will have a seemingly quicker acceleration than your other one. But it will not ping. Any issues overheating? thats also an advanced timing clue...

[jonbonazza]

Bad timing will sound strange... but a ping comes from internal components. Id say you have a bad lifter or something in the valve train. Ive been jacking around with timing alot lately and all it will do is cause a change in your engine performance. if its retarded, it will putter especially at low rpm, and have crappy acceleration. If its advanced, (depending on how much) it will have a seemingly quicker acceleration than your other one. But it will not ping. Any issues overheating? thats also an advanced timing clue...

You are correct on your Base timing, however, your ignition timing can def cause "knock" if advanced too far.

[Az3g]

You are correct on your Base timing, however, your ignition timing can def cause "knock" if advanced too far.

yes, of course, as it is an interference engine youd get alot more than a ping if its too far advanced...

[waynerwats]

I still say try a higher grade of fuel first if possible. Pinging is caused by detonation. Detonation is a bad thing. The lower octane fuels burn faster causing more heat. More heat makes the possibility of detonation higher. My 96 GS pings like mad if I run 87 octane fuel in it. if i put in 89 it goes away.

[Az3g]

I still say try a higher grade of fuel first if possible. Pinging is caused by detonation. Detonation is a bad thing. The lower octane fuels burn faster causing more heat. More heat makes the possibility of detonation higher. My 96 GS pings like mad if I run 87 octane fuel in it. if i put in 89 it goes away.

I would try this too. what the heck. But a lean condition would cause popping, not a pinging noise... at least in my experience.

[jonbonazza]

I still say try a higher grade of fuel first if possible. Pinging is caused by detonation. Detonation is a bad thing. The lower octane fuels burn faster causing more heat. More heat makes the possibility of detonation higher. My 96 GS pings like mad if I run 87 octane fuel in it. if i put in 89 it goes away.

A lower grade fuel than required will cause this, yes, but if the car requires 87 and you run 87 nad hear pinging, then something is causing it as it is not supposed to hear pinging with 87 octane fuel. NORMALLY this is caused by the compresssion or the ignition timing. If it has stock internals, then that pretty much rules out the compression factory and leaves ignition timeing.

[Az3g]

A lower grade fuel than required will cause this, yes, but if the car requires 87 and you run 87 nad hear pinging, then something is causing it as it is not supposed to hear pinging with 87 octane fuel. NORMALLY this is caused by the compresssion or the ignition timing. If it has stock internals, then that pretty much rules out the compression factory and leaves ignition timeing.

agreed on the fuel thing, but I do think its internal. I hope for his sake its just a matter of turning the timing down.