Ignition Timing

[Timon]

I seem to be having a small problem with the ignition timing. I have an inductive timing light that I'm using. I have it set up properly per the instructions, and the light strobes every time the #1 cylinder fires. The problem is seeing the notches on the pulley. From my understanding the strobing is suppose to make it look like the pulley is standing still, allowing you to clearly see the notches, but this isn't the case. It attempts to, but the notches don't exactly stay put.

The notches go kind of like this:

Originally Posted by Pulley

1st
0*----------10*-----16*
|__________|______|

2nd
---0*----------10*------16*
___|__________|_______|

1st
0*----------10*-----16*
|__________|______|

2nd
---0*----------10*------16*
___|__________|_______|

As the pulley is spinning it seems like the notches are vibrating back and forth, repeating between 1st and 2nd as noted above. This makes it kind of difficult to adjust the timing properly.

Advice?

[Jackstand Queen]

Did you short circuit the two leads inside the Testing Connector located high up on the Driver's side of the rear engine bay?

Connecting two particular leads in this is supposed to make it possible to time the motor using an old fashioned timing light.

[Timon]

I'm not sure what you mean by old fashion, but yes I jumpered terminals E1 and T in the diagnostic connector. This actually removes the engine controlled idle, allowing the engine to idle mechanically.

I've done everything step by step, so any other ideas?

[Jackstand Queen]

Check for wiring being weakened by flexing (hanging on by a thread) around the Distributor, and ignitor.

Plug in your Spare Ignitor and see if its your ignitor. I have a Spare N.A. ignitor for 85 to 87's. Or you can pick one up off Ebay for very little money.

Plug in your spare ECU and see if the ECU is the problem. Again I have a spare for N.A.'s.

Yes, Timing lights are way Old School. Now you just plug your car into a $100K plus engine analyzer and get the timing that way. Isn't progress wonderful?

With cars and their associated electronics being as old as they are, keeping a stock of spare critical parts is a good idea.

[ve2dict]

for he record i just move the distributer till it sounds right ...then test drive....maybe move it a hair one way, test drive, try the other way, test drive....oh the first way was better, try that plus more, oh thats worse, move it back a bit ...oh thats good right on

[Gotanmr2]

Originally Posted by ve2dict

for he record i just move the distributer till it sounds right ...then test drive....maybe move it a hair one way, test drive, try the other way, test drive....oh the first way was better, try that plus more, oh thats worse, move it back a bit ...oh thats good right on

He isnt the only one either

[Timon]

Lol, that's like using a butt-dyno. It feels fast, but who knows what power you're actually getting.

[Gotanmr2]

Originally Posted by Timon

Lol, that's like using a butt-dyno. It feels fast, but who knows what power you're actually getting.

Well i guess my sc12 is putting down 300 at the wheels then

[val]

Not to bring back a 2 yr old post, but this is about where im stuck at...

having finally had the time to go out to the car and work on her, I was able to remove the dizy, put a new o-ring on, turned the crankshaft to TDC, installed dizy (with divits aligned to the best of my abilities) and got the car to start. YAY me!!!!!...........now im stuck.

I can get the car to start and idle at 740-800 rpms with jumbers not bridged.

Heres the issue now. I cant get the whole how to use a timing light correctly. I keep thinking perhaps its something i should not do in daylight and do it more towards sunset ? idk. Or should I set the crank to the 2nd mark (as the pic above shows?) im really confused, and i cant move the dizzy anymore towards the right (if ur facing the towards the front of the car ---->) which the idle seams to get better when i adjust it that way. (Car dies if i go to the left)

any ideas?

[dirocyn]

Set your idle to 800 rpms, with the jumpers bridged you should have timing around the 10* mark. With the jumpers off it should be at about 16.

[val]

i never thought about setting the idle.. HA, should i just adjust the throttle nut? or should i do the afm as well??? i thought there was something i had missed. =D

[dirocyn]

The idle screw near the tps is easier. Another thought, the timing mark will jump all over the place if you're not firing on all 4 cylinders.

[val]

When the weather clears up ill go mess with the screw.

how or what would be the best way to test if im firing on all 4 cylinders?

[val]

I managed to get my timing done and the care fires right off the bat. doesnt take 2-3 trys like it use too. All four cylinders fire, Car runs like a champ, the issue now is I can't lower the RPMs from 1500-2000. The idle screw is turned all the way, and if i turn the other way, the RPMs rise. Any solutions? (jumpers are bridged when im doing this too.)

[dirocyn]

Glad to hear you got the timing right, and it helped. If your idle's that high with the idle screw bottomed out, that means you've got a vacuum leak--air is getting into the manifold by some route other than past the throttle plate. Check for a hose that's broken or disconnected, if you don't find those, check for cracks in the exhaust manifold near the EGR tube.

[val]

i had a broken tube that connects the tvis to the cam cover, but that didnt fix the issue when i replaced it. ill check around the rest of tubes. im just glad i got it done.

I do have one other thing, When i was moving the dizzy around to get the timing down, the RPMs would increase, would this have issues with this or be the cause?

[supraguy@aol]

RPM will increase as you advance the timing.
I suggest you check to make sure that your throttle cable/linkage is not stuck or binding.
This happened just the other day to my supra- I jiggled some wires, and didn't notice it, but my throttle cable sleeve got stuck on the edge of the sleeve's housing, pulling the cable slightly, and causing it to idle between 1400-2000. Easy fix though.

[val]

So then perhaps I just have the timing advanced. It was bright out when I did the timing and its hard to check with a light when its bright out. Ill do a run down of the whole thing again tomorrow. Since the family will be at the wifes parents (and the parents hate me for who knows what...[one in every fam. i guess] ) ill mess with it tell they all get back home for xmass presents.

[dirocyn]

I don't think overly-advanced timing will raise the idle to 2000 rpms. I've never seen spark timing effect idle by more than maybe 200 rpms. Don't try to set your idle by turning the distributor, that will only make your car run for crap. The only thing that causes idle to be 1000 rpms too high is too much air getting into the cylinders. Usually it's a vac leak, sometimes the throttle's stuck open, sometimes the throttle cable's too tight, I've seen one car with a chunk missing from the throttle plate. But the issue is definitely air--your challenge is to figure out where it's getting in.

There are multiple methods, I usually start with a mechanic's stethoscope (a couple feet of rubber tubing) to listen for a hissing noise around the vac hoses, it can really help isolate sounds. If that doesn't find it, I use carb cleaner to hunt for vac leaks--if you spray it where the leak is, the idle slows down. Spray it around the intake manifold gasket, around all the hoses that connect to the intake manifold, and around the EGR tubing. If you haven't found the leak by the time you've used up a whole can of carb cleaner, better take a look at your throttle plate and exhaust manifold.

[val]

never thought about carb cleaner. Ill have to get some. What areas should I mostly focus on?