Help, car pinging

Swooki
Club4AG Enthusiast
Posts: 115
Joined: Wed Dec 21, 2016 1:48 pm

Help, car pinging

Postby Swooki » Tue Dec 12, 2017 1:26 pm

Hello i have a 1985 AE86 GTS with 16v 4age blue top and someone told me that my car is pinging and i shouldn't gas the car until i pass 3k RPM. I don't understand what he meant by it is pinging because i couldn't hear anything.... any clue?

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jondee86
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Joined: Fri Jan 11, 2013 10:21 pm
Location: Wellington, New Zealand

Re: Help, car pinging

Postby jondee86 » Tue Dec 12, 2017 2:45 pm

Pinging or pinking is usually heard as a distinct rattling sound when you give the car
a lot of gas at low rpm's in a high gear. Not unlike the noise a paint rattle can makes
when it ia almost empty and you shake it vigorously. Or perhaps if you imagine several
very small people inside your engine with very small hammers pounding on the block :D

Usual cause is too much ignition advance for the fuel you are using. Loosen off the
bolts that hold the distributor in position and turn the dissy a fraction clockwise. About
1/8" of movement at the bolt should fix it. If you have a timing light and can see the
marks on the lower timing belt cover, you should see 15-17 deg advance at idle.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

davew7
Club4AG Expert
Posts: 232
Joined: Fri Jun 06, 2014 4:34 am
Location: Michigan

Re: Help, car pinging

Postby davew7 » Wed Dec 13, 2017 4:12 am

The big port is not a torque motor, it needs to rev. Simple solution is a down shift. With that said, it could be bad gas. I would try switching to a different brand of gas, or go to a medium grade first to see if there is any improvement. It is hard to believe that a stock motor has problem with detonation. It could be carbon build up in the chamber or as jondee mentioned a timing issue. Pull the plugs. Then look for any thing that looks like pepper specks on the plug which is an indication of spark knock. I have away ran more spark advance and never had any issues, even with higher CR. If re-setting your timing verify that the timing mark on the damper outer ring has not moved. I've seen that on several older 4AGE motors, which could be the problem.
Dave W