does the ecu effect timing?

[ASZRAEL1266]

does the ECU effect the timing of the car? when my car is off the data logger shows 5* of timing but as soon as I start the car at idle it shows 13* of timing I am not wiz at dsm's but I know that seems a bit steep. Isn't the stock timing supposed to be around 7ish? what kind of problems could I have with the timing being like this? I wasn't able to get the reading at wot every time I gave it some gas the logger would disconnect. Should I replace my ECU? this is my only car so I have to drive it and I have been driving very carefully and not taking it past 3k rpm unless I am on the freeway in which case I don't take it past 4k. Any info you guys could give me would be great. if the ECU isn't messing with the timing does any one know what else it might be?

 

[taylorspl]

Yes the ECU controls timing, if there is load on the motor the reading will be higher. At idle I usually see ~7-8 degrees with the A/C off and with it on ~12 degrees.

 

[TSi92]

You should set the base timing. Run the car to normal temperature and make sure it idles between 650-800 rpm's and make sure the cooling fan ain't running, the timing should be 8 degrees BTDC. If it's still at 10 you need to rotate the CAS counter clockwise until your base idle timing is 8 degrees.

Hope this helps.

 

[larryd]

How do you get a timing of 5 degrees when the car is off? Shouldnt the timing be 0?

 

[ASZRAEL1266]

i hooked up a data loger the base timing is correct i think it was 5 or 7 not sure but i do remember that it is correct. when i start the car at idle it jumps up to 13 degres. I know my temp sensor is off it shows minus 72 degres at idle when the temp is really only 60 or so out side. Could this be the reason my timing is off by that much? i am also going to recap my ECU wednesday to see if that fixes it. Any info you guys could give me would be great. THanks alot.

 

[larryd]

I still dont understand how you can even get a timing reading with the car off.. that makes no sense to me.

 

[ASZRAEL1266]

to get the timing while the car was off it wasn't really off i has the key turned so all the power is on but the car is not started. I used the data loger to check for error codes and make sure everything was working and it gave the timing. That is how i got the timing. I hope that makes a little more sense.

 

[larryd]

Im sorry Im having a stupid moment. What I dont understand is how the car can even get a timing reading from the ECU if the crank isnt spinning. Thats basically what confuses me.

 

[ASZRAEL1266]

That i am not sure. My friend who hooked up their data loger to my car told me my timing was was that, when we started the car the data loger keept dissconnecting but it showed the timing at idle at 13* i will email them and see if they can asnwer how it got the timing while the car was off. Maybe they just assumed it was that and the cars timing was correct and the ecu was advancing it on its own. Is there any way that you know of to check that to see if the base timing is correct? I am getting my ecu recaped this weekend so i hope that will fix the problem.

 

[larryd]

you check base timing with a timing light with the car idling.

 

[turbo2ltr]

Yes, the ECU has complete control over timing. It is important that your base timing be set properly (5* on a 1G) or:
1: The actual timing will differ from what is displayed on the logger the number of degrees your base timing is off
2: The ECU will use timing to compensate for bad idle caused by the wrong base timing. This will show up as adnormal idle timing.

The first thing I would do is check your base timing with a timing light (it cannot be done with the logger alone). Carefully follow the directions in the service manual and *make sure the logger is unplugged*.

On a 1G, the ECU puts out the base timing even when the car is off. If the ECU is not messing with the timing signal (which it cant when the car is off) then the actual timing would be the base timing of 5*.

I'm not sure, but I think OBDII does not do this. If the car is off, it reports zero degrees.

Base 1G timing at idle shown on the logger is typpically around 9-10 deg.

You should fix your temp sensor. Sounds like the wire is broken or disconnected. (-72 is the lower limit). This will cause you to run really rich (which may indirectly effect idle timing)

If you havent done the caps, it should certainly be done immediately (it might already be too late..)



Regards,
Mike Montalvo
digital tuning, inc.
www.pocketlogger.com

 

[ASZRAEL1266]

i am doing the caps saterday and the temp thermomister i know i spelled it wrong is broken i took my maf off and put it next to my friends and the little diode next to the berometric presure thing is snaped in half. i looked on the tech manurel and it does not give a value for it do any of you know what the value of it is so i can buy a new one and put it on?

 

[DrZiplok]

Just to follow up on this post, since it got hashed out in private mail and on the bay-dsms group, the thermistor appears to be a glass-encapsulated NTC type with pretty typical R25 and B25/50 values. If I get a good replacement part number, I'll post it here on the off chance that someone actually cares. 8)

 

[ASZRAEL1266]

i checked my ecu sunday, i pulled it out and was going to have it recaped only to find that the ecu in the car is new. it had a sticker on it showing it was installed in jan of 01. i am going to replace the thermister as soon as i get a new one. I hope this will fix my timing problem and that my CE light will turn off.