reading spark plugs

[v8vega355]

finally got my car boosted and tuned. for 2 days it was good then i noticed it started to ping. dont matted it its hot or cold out it still pings so i wanted to back the distributor off a few degrees.

does any one have a picture showing what they should look like with to much timing and when its correct

[93redcb7]

http://3.bp.blogspot.com/-pOAwN1wb5M..._condition.jpg

found that for you

[deevergote]

Reading the plugs won't necessarily tell you if the issue is with timing. It's more a gauge of how much fuel is being sent, and how well it's being burned.

Also, if you're experiencing detonation so soon after a tune, I'd suggest rallying the villagers, picking up some torches and pitchforks, and paying your "tuner" a visit.

[v8vega355]

when i was going to pick the car up he said that i may have something wrong with the dizzy, he pulled 10deg of timing out of it and it didnt drop any power so then he made another pull to double check everything and it didnt ping there or for the first whole day. at the end of the pulls he pulled a plug to look at it and he said it was good. when i pulled a plug it had a green tinge to the ground electrode but was pretty white at the positive ceramic.

but the timing thing kind of dont make much sense to me because there isnt really nothing in the dizzy that controls timing unless the igniter does and if thats the case then thats all it should need. i always thought the igniter gets a signal from the ecm to fire the coil, or does the igniter get the signal straight from the dizzy the the ecu tells it to back off or go more?

ill be going back there on tuesday and see what he says too. i backed the dist off a few deg and it isnt pinging at all right now so ill leave it until tuesday like that

[98vtec]

Reading the plugs won't necessarily tell you if the issue is with timing. It's more a gauge of how much fuel is being sent, and how well it's being burned.

Also, if you're experiencing detonation so soon after a tune, I'd suggest rallying the villagers, picking up some torches and pitchforks, and paying your "tuner" a visit.

You can most certainly determine whether or not an engine can withstand more or use less timing from looking at a NEW spark plug.

[GhostAccord]

You can see timing, fuel, heat range and detonation on a spark plug. There is definitely a science to it. You are not going to be able to read as accurately if they have been run in a car for a few miles though. Tuning via spark plugs is usually done on a drag strip where you do one 3rd gear run and read the plugs right away. Even then there is a certain way to do it.

But in general, you can read the general condition of the combustion chamber from used spark plugs.

[v8vega355]

so i stopped by the shop and he explained what was going on. he thinks that the tone wheel(s) for each sensor may not be in the correct position there for i need to replace the dist because of that.

even with the old engine it always seemed like it had to much timing when lightly reving the engine i had to retard the timing a lot to get rid of the light knocking sound it always had. but the base timing was basically zero when the noise went away.

[98vtec]

so i stopped by the shop and he explained what was going on. he thinks that the tone wheel(s) for each sensor may not be in the correct position there for i need to replace the dist because of that.

even with the old engine it always seemed like it had to much timing when lightly reving the engine i had to retard the timing a lot to get rid of the light knocking sound it always had. but the base timing was basically zero when the noise went away.

base timing cant be "zero". Base timing should be set at 15-16* BTDC with the ignition locked so the actual base timing is accurate and sync'd with the software.

I have seen bad gas do the same thing and you have to be extra careful where you fill up with a boosted engine.

[v8vega355]

yes base timing should be set around there. i was just saying for the light knocking sound to go away i would have to set it around 0.

i was just saying both engines made the same sound when the base timing was set correctly and i lightly revved the engines they both had a light knocking sound to them like there was to much timing in it. both were compaired when the car was running on a stock ecu, tune and still na.

btw sucks having to fill up with super everytime lol

[98vtec]

yes base timing should be set around there. i was just saying for the light knocking sound to go away i would have to set it around 0.

i was just saying both engines made the same sound when the base timing was set correctly and i lightly revved the engines they both had a light knocking sound to them like there was to much timing in it. both were compaired when the car was running on a stock ecu, tune and still na.

btw sucks having to fill up with super everytime lol

It took a 15* retard across the board to get the knocking to stop?

If he pulled 10* of timing out of the engine at WOT and it didn't change the power output, the tune was way off to begin with. once the engine is tuned correctly, there will be a difference in power even taking out 2-3* of timing, especially on a boosted engine.

[v8vega355]

It took a 15* retard across the board to get the knocking to stop?

If he pulled 10* of timing out of the engine at WOT and it didn't change the power output, the tune was way off to begin with. once the engine is tuned correctly, there will be a difference in power even taking out 2-3* of timing, especially on a boosted engine.

as far as the knocking goes i am referring to before it was tuned and while it was on stock everything. both engines sounded like they had to much base timing with a light rev. but were at proper base timing. the base timing had to be at 0deg before that knocking sound would go away. and it was with both the built engine and the stock 270k mile engine. but since i am using the same dizzy that came from this engine it is cause for concern


yes he pull 10deg out of the engine and it didnt change the power output nor was it pinging. he said the ecu couldnt read the distributor signals correctly because the tone wheels werent seated in the correct places.

[dbsharp]

Is it fixed? Don't go around punching it. Swap the dizzy, and bring it back to the tuner.