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Thread: SR20VE Help Need-Ignition Timing Fighting Me - High RPM Misfire-Sounds Like Anti Lag

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Posts: 41-50 of 68
2015-06-26 08:33:33
#41
Also data log you MAF voltage too.. Once you get your timing working correctly you will see your MAF Voltage go up as you make more HP... the MAF voltage will give you a good idea of where your making your max HP
2015-06-26 08:39:27
#42
I understand. You have to work from the baseline that the ECU Talk is always thinking timing is at 15 base timing. So if I have added 7 degree to base timing I have to add 7 deg to all the timing readings it gives. Correct me if I am wrong.

Side question - Does the ECU use the MAF signal at WOT normally?
2015-06-26 08:55:26
#43
Originally Posted by VE-Baller
I understand. You have to work from the baseline that the ECU Talk is always thinking timing is at 15 base timing. So if I have added 7 degree to base timing I have to add 7 deg to all the timing readings it gives. Correct me if I am wrong.


Yes sir you are 100% correct!!

Side question - Does the ECU use the MAF signal at WOT normally?


Yes... It always uses the MAF.. Its is your most important sensor... Its the metering device so it may know how much fuel to send... MAF is the input to the CPU and the Injectors are the Output ...
2015-06-26 09:24:53
#44
Thanks, I have an AFC NEO. If all else fails Ill put it back on the car. I wanted to check it was not a complete waste of time first
2015-06-26 18:21:30
#45
Originally Posted by VE-Baller
Ok thanks.

This is what the log shows when I have the problem. Foot to the floor but hesitation - Revs rise and fall.

Im pretty sure it tells us nothing.

Summary
3.76 Volts wide open throttle.
4 Volts max MAF
Timing 16
Revs 5500
Injector 65% duty

Time RPM Bat TPS Tim Inj Dty Air Flow
25:02.4 4900 12.96 3.76 15 11.98 48 3.68
25:02.5 4937 12.96 3.76 15 12.08 49 3.7



Here's my take on your datalog.

Battery: The battery voltage is low. You got a dying or already dead alternator. With a healthy working alternator charging, you should see high 13 volts to over 14 volts. Battery voltage by itself is in the 12 volt range.

TPS: is out out of adjustment. Should be .45-.55 at idle and 4 volts at WOT. You don't want to be 4.5 volt at WOT that will send a false disconnected signal to the ecu. Just disconnect the tps and you will see this voltage for the tps.

Timing: is really low. Seems like it's running in a fail safe mode. Again, look at the timing map I posted for reference.

Conclusion is you go a lot of things to sort out.
2015-06-26 20:11:18
#46
You need 4.5V 4.0v Doe's not cut it.. According to Clark @JWT and FSM

Sent from my SM-N900T using Tapatalk
2015-06-26 20:12:12
#47
SR20VE Help Need-Ignition Timing Fighting Me - High RPM Misfire-Sounds Like Anti Lag


Sent from my SM-N900T using Tapatalk
2015-06-26 21:00:32
#48
How to Adjust TPS:

http://www.sr20-forum.com/forced-induction-mechanical/54129-tps-reading-5-closed-but-onky-3-5-wot.html

http://www.sr20-forum.com/general-sr20/16435-tps-bad.html

how to check tps voltage - SR20 Forum


You don't want the TPS to read too high above 4 volts. The engine will run funny. Call Clark @ Jim Wolf and he will tell you the same.
2015-06-26 21:37:20
#49
Originally Posted by VE-Baller
I understand. You have to work from the baseline that the ECU Talk is always thinking timing is at 15 base timing. So if I have added 7 degree to base timing I have to add 7 deg to all the timing readings it gives. Correct me if I am wrong.

Side question - Does the ECU use the MAF signal at WOT normally?


Originally Posted by KillerKrossover
How to Adjust TPS:



http://www.sr20-forum.com/forced-induction-mechanical/54129-tps-reading-5-closed-but-onky-3-5-wot.html

http://www.sr20-forum.com/general-sr20/16435-tps-bad.html

how to check tps voltage - SR20 Forum


You don't want the TPS to read too high above 4 volts. The engine will run funny. Call Clark @ Jim Wolf and he will tell you the same.



I can drive over there... There good friends.. Use to work on our cars there on the weekends.. My buddy George use to work there... Jim,Clark & Mike Smith & Mike Kojima have all been good teachers over the years (20yr now I might add)... In any case I am sure you are mistaken at the 4V .. Even the FSM says 4.5V ... I posted the spec sheet on it from the FSM as well... 90deg should be 4.5V per FSM ... Ultimately check what ECU Talk says the computer is commanding... You may not see full timing tell your at that 4.5V .. The stock ECU is 100% Junk.. This is why I build my own ECU's and get the engine to do EXACTLY what I want when I want.. I can build full PNP units for OBD1 & OBD2 for under $400.. Also a great little unit is the MicroSquirt with 8' harness for like $385 retail to the end user.. Connect your CAS,CLT,TPS for inputs and Injectors,Coil,Fan & VVL for output and your done... Simple Simple to do .. Its not too hard...
2015-06-26 21:56:47
#50
Your potential power supply problem!!! Lots of our cars have them... ALSO check pins 1 & 3 at the TPS .. YOU NEED TO SEE 5V .. If not then the VREF regulator in the ECU may be going bad.. You would need to check the resistance on the wire @ a 5A load unhooked ... OR Power at the ECU output on VREF(5V)

Also check your voltage at the ALT + post and ALT Body - ... If your voltage is not the same as the datalog and I am almost sure it will not because are cars are OLD ... Almost all our old cars have a massive voltage drop... Anything over 300mA with a fully charged battery is a fail ... We only have 10gA power feed from our ALT .. 10GA is only good for 30A at most .. Our ALTS are more then that and if you had a low battery over time it hurts the electrical ... Then do a Voltage drop test from ALT + to the ECU main power supply . Pin 36 is IGN switch and is pre ECU power but check there... Pin 36 opens power to ECU then ECU Opens ground to Pin 4 (neg trigger to ECCS Relay) then primary power comes back in on pins 47,38 ... So also do a voltage drop test from 36 to 47&38 .. If the voltage is drastic from 36 to 47,38 you can T them together to get a better power supply to the ECU just remember its unfused at that point and you may want to put in a 3-5A fuse ..
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