jeffbrewer80

OK, when you are using a high-end digital Timing Light that lets you set the degrees by using up and down buttons, do you set it to 12 degrees and then make it so that TDC (white line) is at the bottom pointer or do you make it so the BTDC (red, 12 degree mark) is at the bottom pointer?

A tech I work with that usually works on domestics said it's supposed to be the TDC mark at the pointer if the timing light is already set to 12 degrees, because if you set the timing light to 12 degrees and then make the BTDC mark reach the pointer, you are basically setting it to double that? He's using ax expensive Snap-On one so I don't know if they work differently or not?

I am confused!

It's a D16Y8, 98 Civic EX. It has the 3 marks close together "I I I" representing 10, 12 and 14 degrees. And then it has the one "I" by itself about an inch to the right of the other three representing TDC, or 0 degrees.

grumblemarc

iTrader: (4)

What's so difficult?
http://www.hondacivicforum.com/forum...ustment-16210/

Former User

Also see diagram in FAQs sticky.

kyden

if you set the timing light to 12 degrees on the led, the mark you want on the crank pulley should be at 0 degrees (usually white)

jeffbrewer80

OK perfect that was my question kyden. I just simply needed to know whether you line up the RED mark with the light set to ZERO or line in it up set to TWELVE.

:-)

kyden

you can put the light to 0 and match up the red mark if you wanted to.

jeffbrewer80

OK and one last thing: when looking at SPARK ADVANCE on a Scan Tool, is that the Output or the Input? In other words is the screen showing just what the ECM is commanding or is it showing the actual timing?

Former User

Both - if the service connector is not jumped.

Jumping the service connector prevents the ECU from adjusting the ignition timing.

As an aside, it seems to me that you are making the job of setting the ignition timing more complex than it should be. Just jump the service connector and then use the basic features of an inductive timing gun to align the pointer to the red mark on the crank pulley -- simple as that.

jeffbrewer80

I guess it just feels like I still don't 100% understand.

Is the SPARK ADVANCE on a Scan Tool an INPUT or OUTPUT? With the connector jumped, will it display the BTDC degrees or not? Or is that value on the screen just the OUTPUT to the module and not the actual reading?

Because if it's an INPUT that reads the exact timing with the jumper connected, wouldn't it be easier to do it that way than using a Timing Light?

Former User

It displaying output from the ECU.

The reason you don't use the scan tool to set the ignition timing is because it's output reading of ignition timing ASSUMES that the ignition timing has been properly set using a timing gun.

Again, you are over complicating an otherwise simple procedure. Turn off all fancy settings on your inductive timing gun and adjust the ignition timing so that the pointer aligns with the red mark on the crank pulley. Done.

jeffbrewer80

OK so last question:

Basically you can set the timing using either of these:

1) Leave Timing Gun on ZERO DEGREES and make it so the WHITE TDC mark is at the pointer

2) Set Timing Gun to TWELVE DEGREES and make it so the RED BTDC mark is at the pointer

Either way will set the timing to the correct spec, right?

If the answer to this question is YES, than I will NOW UNDERSTAND!

92lxsleeper

other way around 0-red 12 - white

Former User

This^

Corrections:

In the future, buy yourself a basic inductive timing light with no fancy functions and then follow the instructions in the service manual.