Help! Timing Problem

[md_83gt]

Hi. I’m new to the forum. I love the old school Toyotas; my brother has an 78 corona that I loved so I bought a 83 Celica.
The Celica is in great condition and has only 85k original but has a random misfire in which it hits around 15 degrees every once every 7 or so light burst instead of 5 degrees, not running at its best, and only gets 20.5 mpg.
The cylinder and vacuum pressure are great, trans fluid is clear w/o shards and breaks don’t drag. I recently did a tune-up (problem was there b4 tune up) I adjusted the timing and rpm. Replaced the sparkplugs, wires, distributor, rotor, oil, oil filter, fuel filter, and added fuel injector cleaner, air cleaner was fine.
Things I’ve noted. Rpm starts fine but drops after a seconded when car first started, after a few minutes it seems to behave right. Car rumbles when shifting gears (automatic). Timing seems to advance fine but I only have the idle timing from the repair manual (5 degrees). I was told by some one that I should short out the “diagnostic connector” when adjusting the timing, I don’t know what this looks like, how I short it out, or if this will even help.
Any input on this would be helpful

Thanks
Walter

[digmycelica]

Originally Posted by md_83gt

Hi. I’m new to the forum. I love the old school Toyotas; my brother has an 78 corona that I loved so I bought a 83 Celica.
The Celica is in great condition and has only 85k original but has a random misfire in which it hits around 15 degrees every once every 7 or so light burst instead of 5 degrees, not running at its best, and only gets 20.5 mpg.
The cylinder and vacuum pressure are great, trans fluid is clear w/o shards and breaks don’t drag. I recently did a tune-up (problem was there b4 tune up) I adjusted the timing and rpm. Replaced the sparkplugs, wires, distributor, rotor, oil, oil filter, fuel filter, and added fuel injector cleaner, air cleaner was fine.
Things I’ve noted. Rpm starts fine but drops after a seconded when car first started, after a few minutes it seems to behave right. Car rumbles when shifting gears (automatic). Timing seems to advance fine but I only have the idle timing from the repair manual (5 degrees). I was told by some one that I should short out the “diagnostic connector” when adjusting the timing, I don’t know what this looks like, how I short it out, or if this will even help.
Any input on this would be helpful

Thanks
Walter

Is this a carb or fuel injection engine 22r or 22re ?
Does the dist. have vacuum hoses?

[md_83gt]

22RE (fuel injected).
the distributor does have vacuum hoses attached to it, hoses themselves seem clear and to hold pressure.

[digmycelica]

Originally Posted by md_83gt

22RE (fuel injected).
the distributor does have vacuum hoses attached to it, hoses themselves seem clear and to hold pressure.

Unhook both hoses on the distributor after the engine is warm and plug them with something so they can't suck air. then set the timing to 5 degrees.
Then plug hoses back up to dist.

[md_83gt]

Timing is better (still does it alittle), but the car still runs alittle rough.
Checked the spark plugs today and they have a layer of carbon on them (not oil), they were only in for around 1k. Related to timing?

[digmycelica]

Originally Posted by md_83gt

Timing is better (still does it alittle), but the car still runs alittle rough.
Checked the spark plugs today and they have a layer of carbon on them (not oil), they were only in for around 1k. Related to timing?

Is the antifreeze getting out slowly?
It might be a head gasket seeping antifreeze in the cylinder. causing the white on the plugs.
if not that then while it's running, spray a little carb or brake cleaner spray around the intake and see if the idle gets faster or smooths out when you spray it. if it does then you have a vacuum leak or intake gasket leak. just be careful not to spray it on the exhaust because it's flammable

[Doctor J]

Check the following items:
the hose to fuel pressure regulator;
the coolant thermosensor, wires and connector
the idle mixture adjustment screw on the air flow meter for evidence of tampering