1996 Geo Tracker hesitation upon quick acceleration

[fixkick]

for sure you are on track , all tests are very revealing.
you must use the timing freeze jumper. i see you did. good. but that jumper only works near 800 rpm ,hot and TPS idle switch closed.
the ECU uses timing advance, to fast tune idle speed. (then ISC slow but more control ) this fast idle servo , is defeated in timing freeze .
if not you, will just get a bouncing timing mark with strobe light..

also the damper pulley on the car LOVES to de-laminate that rubber bond slips. the cure is new damper , or short term do a TDC recalibrate on the pulley using TDC tool.

used dizzy's , rotor planted wrong, 1 of 3 is good. other 2 are, dead spark and weak yellow spark. ( this error puts the CMP hall sensor star wheel out of time with rotor, causes spark between , cap posts. and horrific results)
used dizzy's, some one took off the gear in end and put it on 180deg out., this makes out of time gear, causes, the rotor to land wrong.

1530 only means , timing freeze jumper forgot to remove it...


it will run, but timing must be good.


the dizzy timing is easier to see on the old 8v TBI engine
seen here clearly , the 16v this harder to see, causally.

crank shaft key good>, crank-pulley not stripped out >then cam timed right, then dizzy gear right>, then rotor right,> and last timed with a strobe.

the tabs in the hall wheel, must be at the correct location, and the rotor to land on the right cap location. This wheel tells ECU where TDC is.


the dizzy can be timed at any cap tower , point, but 1pm is normal for the harness to fit right.
this is because the ECU dont know what hall tab you are using, to fire TDC. the dizzy (fitted right) is perfectly symmetrical. (rotor and gear planted right)


if the gear is wrong on end of dizzy, you will find the slot in the adjustment base has too little range... a very frustrating , event.


16v , normal location
http://www.fixkick.com/IGN_timing/16-rea...zy1c1w.jpg

[gorkyb]

Quote:

"if the gear is wrong on end of dizzy, you will find the slot in the adjustment base has too little range... a very frustrating , event." <--- I could not have described it better, this is exactly what is happening to me, I don't have enough range. I'll take gear off spare distributor (on car now) and turn it 180 degrees and try again.

On the original distributor I took off yesterday, both of my rotors only go in one way. Can I troubleshoot the yellow/weak spark or is this distributor gone?

[fixkick]

yes, many others have reported this. (all theory because ive not seen it with eyes. myself this odd failure "slot fail")
they drop the dizzy, many times down base hole 13 teeth (IIRC) and not matter what, you can not get the range you need in the base slot.
it can only be that, or cam belt, off 1 tooth.
the other factor here is the CKP sensor corrects the errors, in CMP. in 1996.
so crank cog tone spikes on crank code set up perfect zero degree's
so any error seen at spark plug (timing) starts there. and works upward.
you are close to finding it. im sure. i hope is something simple and easy to fix. and not a belt issue.

[gorkyb]

So I took the suspected distributor with the gear backwards out. Looked closely and compared it to the one that originally came with the Tracker. The pin that secures the gear is very different, one is a spring pin (the one that came with the car) and the other one it's a solid pin that looks pressed in. Since I don't have a press at home, I decided to give the distributor a try again. I pointed the middle of the rotor to the middle of the HV post and the set it in which made it land pretty close to where #1 wire plugs into. Started the car with the torx bolt in the middle of the slot and it barely stayed running, I moved it all the way to the left of the slot (looking at the torx bolt face to torx head) and it ran a lot better, however still not on zero degrees or 5 degrees advanced at it should, it looked like 10 degrees retarted. So I took it out again and moved the rotor counter clockwise one tooth before setting the distributor in. Started the car again with torx bolt in the middle of the slot and car ran a lot better. All this time the RPM's had been at or very close to 800 and in proper operating temperature. I then tuned it with the strobe light and moving the distributor so the torx bolt is "almost" all the way to the right (looking at the torx bolt face to torx head) I was able to get a steady 5 degrees BTDC.

Car ran smooth for an hour, took it to the gas station and to the autoparts to get a new battery and it ran perfectly. No bogs, hesitation or misfires. No codes stored. I also put brand new NGK spark plug wires.

The only thing left I have now is an oil leak which I'll post in a separate thread.

Thanks for all the help. Hopefully this time it will stay running for a while.

[fixkick]

RE: 1996 Geo Tracker hesitation upon quick acceleration
you Nailed it.
fine work that,