Thread: spark plugs fouled with dry black carbon?!?!

my iginiton timing at idle through aem says it is 6.555 degrees, that doesnt sound right, that cold be causing weak spark?

Not weak spark, but premature spark. Fuel isn't getting ignited fully.

Shouldn't it be more advanced than that even for idle? I agree with tekkie, if they are firing too late at idle you're going to end up on the rich side and foul up those plugs.

but the thnig is, NOTHING on the iginiton side of the engine has been touched, the distributor hasnt been moved, and my AEM still is reading 10 degee's like the tuner set it to and eerything?

though my aem my injectors are reading with the key on engine off... 35215 and mytor duty injec says 0.10% does that mean they are leaking or what?

im also seeing 0.04volts for one o2 sensor and 0.02 volts for the other sensor?

Idk haha maybe it's worth a shot to advance it a bit and see if it changes? I mean with the EMS you are able to adjust it per RPM no? So you could advance idle but leave the throttle the same? Maybe I'm just confusing myself

Also you said 6.6 before not 10

10 degrees is still retarded. STOCK the timing should be between 15~17 degrees at idle. This is BASE timing. The ECU is going to add/pull timing where it needs to according to your map.

Base timing should always be at 15 degrees. Put the car in timing mode and advance it to 15~17 degrees.

with the key on and engine off, the timng says 10.7... the tuner said that they always tune turb cars with timing at 10 degrees, i didnt ask why, but i mean the car doesnt lag at all, and i havent had any issues with the car at that timing, so i donno with the car started i was seeing 6 degrees, altho it was missing too i donno if that wll effect anything or not.

but i mean, should there be any percentage with the injector duty with the car off? or is that a sign of he injectors leaking? becuase they are all in sync with eachother but i am seing a ijector duty with the engine off

Probably because they give you a base tune right? They don't want to risk advancing a turbo car because of possible knock probably?

I don't see how it could tell you an accurate timing with the engine off so I would go with the 6 degrees while it's running.. You can always check it the old fashioned way though to be sure haha.

I don't know anything about the EMS so I can't answer your injector question, but timing seems like it's worth a shot to advance at base a little.

IIRC, you should see something as far as duty cycle with the motor off and in the ACC position. You don't really see "duty cycle" but rather the resistance of the injector with power applied.