bubbaz28

1983 Z-24 LG4, q-jet... 305 5-speed stick

Sorry guys... I can't seem to find the stupid EST wire so I can set my timing... I/m looking for a tan with black striped wire to unplug, and see no such wire...

I have looked around the passenger side firewall for it- no luck.

Is it the grayish wire with tan plug seen in the photo that I have partially unplugged? (With this wire unplugged, tach is out and car idles so low it quits quickly if I don't give it some gas.)

Thanks again!

8t2 z-chev

there is no EST wire on a carb third gen-instead,the 4-wire plug from the distributor base to the ECM harness is disconnected to put in "bypass"and set timing.

bubbaz28

Hi 8t2 z-chev,

Is that the plug with the black connector seen in this picture? I thought that was the one, but (A) it only has 3 pins, and (B) car won't start with that disconnected-

8t2 z-chev

nope.the EST plug is on the other side of the distributor base-wide flat,plug and often found lying atop the bell housing area-4 wires from base ~5-6"long before the plug.

bubbaz28

This one? Seems to come from under the distributor- has 4 wires...

Thanks again for helping a newbie.

8t2 z-chev

I think that one is for the heater.From the pics,looks like your EST wires are straight back towards the firewall.

bubbaz28

God, what a pain!

I was able to find the wires from the base of the dizzy, behind it... they seem to come around to the driver's side, against the firewall... there is a 2 contact, weather pack connector with a kinda tan wire with black stripe.

sofakingdom

iTrader: (1)

That's not it. Neither one.

Neither is particularly close to the base of the dist either, for that matter.

The first one is the A/C compressor and high-speed blower wiring, and is kinda on top of the valve cover. The 2nd, not sure; but it doesn't have the right # of wires, and of course isn't in the right place. It's between the brake booster and the driver's side fender. Not really even in the same zip code even.

There is a 4-wire harness hanging out of the bottom of the dist base, around the edge, should be coming out the very back. Has a Weatherpak connector somewhat similar to the one in your pic, except for the # of wires. (4...) If you feel around the bottom of the dist base, you'll find it. Prolly hangs down sort of under & behind the firewall, kinda on top of the transmission. It has a pigtail about 10" long coming out of the dist going to the mating plug from the harness. Looks kinda like this. http://www.autozone.com/ignition-tun...?checkfit=true

You unplug that, start the car, it will run like HAMMERED DOG CRAP, the SES light will come on, you set the timing, turn the car off, restart the car, light will go off. Next time you drive the car you'll discover you probably just wasted your time, since as long as nobody messes with it, it doesn't change. It stays right where it's put. Odds are, in fact, that it's correct now (unless somebody has messed with it already), and if you mess with it, it'll be wrong.

You'll also find that the car will run AWHOLEHELLUVALOT better if you DON'T set it at the factory "spec". Keep in mind, that "spec" serves MANY masters, one of the LEAST of which is, how well the car runs. That motor will usually run better with it set at around 6 - 8° more BTDC than the "spec".

Looks like a trip to the quarter car wash to clean up the engine bay would be in order.

bubbaz28

Well, I tried to follow the wires from the back of the distributor as best as I could. Very hard to get my hand back there of course, and they quickly disappear into a bundle of other wires. I won't bother you all with any more pointless photos that are obviously wrong.

I am not dead set on changing the timing, I'd just like to use the timing light and see if it appears to be off.

I also found the following info. concerning diagnostic procedures- from the Chevy manual I have... #4 seems to say that grounding the test lead terminal with the engine running will do the same thing as disconnecting the EST wire? "Cause EST to be set at a fixed spark advance to be used for setting base timing....? Again, I may be wrong- clearly I am not as gifted mechanically as my old man was. Just trying to pick up where he left off.

And yes, I'll clean the offending engine bay soon.