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hgallegos915 wrote:I had advanced timing for like a week..i removed the battery for a while restarted and boom..advanced timing gone :*( I moved disty all the way up ..down.. no change in speed... just spits a bit when its all thje way up. bleh .
:*(

Thanks, suspicions confirmed...I think.
Tune's wrt to our pm's, perhaps a clarification to the use of the term advance may be in order. That is to say, a disty has normal timing advance capabilities...that has always been the case - mechanical or electronic. And those advance properties come into play when at speed or at higher than idle rpms. WRT advancing the timing for the purposes of performance we are looking to set the base timing/triggering higher than spec settings. This usually will increase the overall idle speed. When doing normal timing settings the car is diag mode and we are using a timing light to set as per the timing marks on the crank. If you leave the timing light in place, remove car from diag mode you should observe the timing mark on the crank to "self adjust itself because the ECU has been told to do so.
Therefore, if I were to decide that I want to advance my timing ahead of spec settings without the ECU to compensate I would simply rotate the disty in the appropriate direction without the car in the diag mode....at least that's my take on it.

Hector, because you had advanced your timing BUT subsequently removed and reconnected your battery, the ECU had to learn the status/new positions of all of it's connected components. This meant that it saw the position of your disty and made the appropriate compensation to set the timing (electronically) to spec settings.....hence no more self inserted advance. But when you tried to adjust the disty manually afterwards you said things got worse...of course they will.
I believe that you will have to start over again from ground zero. meaning that you must get the timing light out, put in diag mode adjust as per specs using timing marks on the crank as per mormal timing adjust procedures. Once that is completely done and you still want to insert an extra amount of advance, I believe it can be accomplished by the means that I previously mentioned - manually and not in diag mode. If, for whatever reason you have to disconnect the battery again, I believe you will have to go through this complete process again.
So Hector, I think your next step would be is to start from ground zero and do a complete timing adjust by specs and by the book. After that, then decide if you still really want to have an artificially advanced timing set-up.

if I were to decide that I want to advance my timing ahead of spec settings without the ECU to compensate I would simply rotate the disty in the appropriate direction without the car in the diag mode

If you turn the distributor without the jumper.. the ECU will compensate.. To set your initial timing you need that jumper. When you are on the road ECU then adjusts the amount of advance or retard to use based on your initial timing point while you are driving based on load and engine RPMS (and other factors from coolant temp to O2 sensor readings, etc). If you put your timing light on without the jumper wire and watch your timing marks while you goose the throttle.. you will see your timing marks bounce all over the place (in fact, the shop manual even tells you to check and make sure this is occuring after you set your initial timing point) this is because the ECU is adjusting the timing. In Diagnostic mode.. you shouldnt see the marks moving that much with changes in RPMs since the ECU is bypassed via the Jumper wire.

Tunes67

Ok here we go, my experiments for today.

I tried both ways witha nd without the jumper, and jumper is the way it actualy made any difference.

As you turn the distributor manualy without any jumper you will notice that atheres no change in RPM as ECU learns.
Now when you have the jumper set, as you turn the diributor you can hear revs going up, and if you counter turn it they drop as they shgould prooving the jumper theory correct as it eliminates the ECU intrusion.

I put in the jumper and loosened the bolts, turned on the cra and listened for revs, turned clockwise around 5 degrees, turned off teh car, removed the jumper and wallah.

Note: i had to do this few times as i advanced 2 degrees at a time.

I wasnt sure as to operation status of the vehicle as i play with jumper but hope i done nothing wrong

hmm i must try this..im going to go test it right now..be back in a few mins.


-hec

I did it and i did feel a bit opf a different..I noticed my idle was to low for ac..i adjusted timing a bit up abd turned on ac and it wont idle down this time. its running great ... for now. I wonder if the ecu will compensate..

The ECU wont compensate as long as the adjustment to the distributor was made while you had TEN and GND jumpered. After you made the adjustment.. then you remove the jumper wire before turning off the ignition. If you shut down before removing the jumper wire.. or if you didnt use the jumper wire.. then the ECU will compensate or reset to the last known initial timing point.

Tunes67

ooh crap.. I removed the ten and ground after shutting off ignition.. tomorrow ill set it again. I did feel a bit of a difference.

Ok here i will need to disagree.

While car is working , with timing advanced revs speed up, and if you remove the pin while its on you can hear the revs drop back down.

If you set the timing with car on, turn it off remove the pin ad start again it still works with advanced timing/revs.

Unless i dont really understand something, feel free to proove me wrong

Well I suppose my mazda tech could be wrong.. he is the one that told me to do it that way.. and if you check in the online tech manual.. there is no mention of shutting the car down before removing the jumper wire. No offense here man.. but if you shut down and then remove the jumper wire before you start it again.. since the RPMS spike at initial start up.. how can you tell it has or hasnt changed?

Tunes67

Just saying that while it was working and i took out the jumper i heard the drop in revs,,, therefore my conclusion

I did say feel free to proove me wrong.

I am not sure on this one.. its kinda a guess.. but I have noticed the drop in RPM's when removing the Jumper while the car is running as well. I think what is happening isnt the ECU compensating for the timing.. I think its compensating for the increased Idle speed and dropping the RPMS back down to where they were last set via the IAA Screw & TPS location. I could be wrong since I have nothing to base this conclusion on.. but I think that is what is happening. I just know that if I put the jumper back in and check my initial timing again.. it stays put as its supposed to.

Tunes67

hmm around where do you place your disty..i noticed...if its to high..u gain nothing ..if its too low you lose power..medium lose power theres a point between medium and top where its the right spor..anyone got pics?