Driftmotion 1JZ AEMv2 Plug and play Breakup issues at 5500rpm

[Turbo Habanero]

So i'm having trouble with my AEM breaking up/just not going past 5500rpm. I am using DM's base tune and trying to sort this issue out before I go to the dyno.

I have read some info in this thread pointing to Dwell settings and harness issues
http://www.supramania.com/forums/sh...today-and-got-horrible-results-AEM-V2-PNP-1JZ

The revs will stop at 5500rpm no matter what the conditions even free rev it stops there is acts like a rev limiter. every now and again in first gear it will get to redline but not in any other or out of gear.


Car is on stock 1jzgte coils and copper ngk's gapped to .028


Any help or thoughts are welcome and appreciated and or common issues

here are my current dwell settings

 

[Turbo Habanero]

If anyone else is having this ossue i fixed mine by changing the dwell max down to 2.199 car now revs flawlessly

 

[hvyman]

The base tune is just to get you to the dyno. Not meant for much past that.

 

[Dirgle]

By changing this setting you have moved the max dwell time from 2.724ms down to 0.998ms at 5500 RPM. This might not be enough time to charge the coils if you put it under a heavy load.

 

[Turbo Habanero]

I've been doing small tuning my self to make the car drivable because with the base tune it was not. It wouldn't stay on even at idle.

Just trying to fix the hicups vefore going to the dyno. The car currently has great afrs and pulls all the way through redline no hesistation at all since we changed the dwell setting.

Before it wouldn't go past 5500 no matter what not even out of gear at idle.

 

[IJ.]

5500 is usually Spark blowout, you need either less Gap or more Zap, increasing the Dwell around there will give some more Zap but only to a point where you start to overheat the Coils, another way around this issue is to add more Timing from 5200>5500 If you can do this without getting Detonation, the extra advance will drop the cylinder pressures enough to stop it blowing the spark out.

More expensive option is to upgrade the Ignition system.

 

[Dirgle]

5500 is usually Spark blowout, you need either less Gap or more Zap, increasing the Dwell around there will give some more Zap but only to a point where you start to overheat the Coils, another way around this issue is to add more Timing from 5200>5500 If you can do this without getting Detonation, the extra advance will drop the cylinder pressures enough to stop it blowing the spark out.

More expensive option is to upgrade the Ignition system.

What is weird is that he fixed his breakup issue by reducing the max possible dwell time(from 2.724ms down to 0.998ms at 5500rpm). I can only guess that maybe this map is using a different method of basing its dwell calculations on than the 12 tooth wheel giving 24 teeth per cycle. Not sure how though.

 

[Turbo Habanero]

I don't understand why id be getting spark blow issues not under load ...

And even under load im only at 6psi.

 

[IJ.]

Ok if it's happening not loaded there's something seriously amiss Jordan...

You need to go through every table/parameter to see if there's a limiter active.

Do you know anyone with a simular setup that has a working AEM file you could try?

 

[Turbo Habanero]

As you can see in the pic below.

All i did was change the max dwell setting from 6.000 to 2.199 and now the car runs 100% better. Ive read this was a common problem with the AEM DM base tune and that's why i changed it to see if it would work.

 

[IJ.]

Don't really understand "teeth" never having worked with an AEM, Dwell is usually based on MS as units, were the coils getting hot when it ran with the 6.000 setting?

 

[Turbo Habanero]

Ok if it's happening not loaded there's something seriously amiss Jordan...

You need to go through every table/parameter to see if there's a limiter active.

Do you know anyone with a simular setup that has a working AEM file you could try?

Unfortunitly i don't know anyone with a single 1jz setup on AEM. Although my ecu did this same thing when plugging it into my friends 1JZ and my car works fine on a stock Ecu.

The tach also seems to freak out and jump and bounce everywhere when the Dwell Setting is at 6.000 but the tach is perfect when its set at 2.199.

Don't really understand "teeth" never having worked with an AEM, Dwell is usually based on MS as units, were the coils getting hot when it ran with the 6.000 setting?

I'm unsure also. Do you mean hot to the touch ? or is there a way to actually measure the heat ?

 

[Turbo Habanero]

Here are some qoutes from another thread started by OneJArpus having the same issue as i. here i the linked thread also

http://www.supramania.com/forums/sh...today-and-got-horrible-results-AEM-V2-PNP-1JZ

I went to the dyno today and have 7 hours of being there and doing things i have major issues.


It will not free rev or underload go past 5000-5500, it just breaks up so bad. The tuner tried everything with the AEM and couldn't get it to go. He mentioned that the teeth count for the fuel was a little high, 18 vs 6 on a 2j he did a few days ago. He also tried locking the timing at a certain amount but when reving it would just go retard. No check engine light no problem codes nothing... His best advice was to look into the ignition system, coils (which are aftermarket new), ignitor, and so on so forth

Problems when AEM is plugged in:
Free reving under 5k is fine, you can hold it at 3k no problem, but as soon as it starts to get to 5,000 it sounds like a 2step. When under load the same thing, when that happens the tach GOES CRAZY and drops to 1k then back up to 5 and just dances all over the place.


I drove the car home and didnt bother with it as i was disappointed so tomorrow i'll see how it acts...




Aaron was very helpful with giving me the base map, but with it as is it could not start the car, some triggers were set differently and it wouldnt turn on. He did some changes and it started just fine.

I think its ignition because the tachometer goes jumps all over the place when it happens. If it was just a misfire from spark plugs i did not see that happen when i had that spuddering issue before i gapped my iridiums.

Yes i have a resistor pack

sucks that you haven't found out whats wrong with your car yet but i have to say thank you for this thread because i was having the same problem with the aem standalone from DM and mine was that the dwell setting was set at 6 we put it to 2.5 and it started revving freely to 7500rpm so thank you and good luck

My issue ended up being basemap issue. The triggers/timing sync was off. I cant remember the #'s and my laptop is broken so i cant hookup to it right now... show me your coil/injec screen

Also IIRC the coils like to be at 2.0-2.5ms charge time (2.2 comes to mind) not 100% sure though as i have 1zzfe coils now

 

[Dirgle]

Don't really understand "teeth" never having worked with an AEM, Dwell is usually based on MS as units, were the coils getting hot when it ran with the 6.000 setting?

The AEM seems to like doing crazy calculations for simple functions, which is why you see a lot of people who don't like to tune them.
The crank has a 12 tooth ring. two rotations of the crankshaft give us 1 cycle or a total of 24 teeth.
Now here is where the I think the issue might have come up. If it thinks that sensor is on a cam it will calculate 24 teeth = 1 crankshaft rotation, which is incorrect.
But if it sees it as a crank sensor then every 12 teeth = 1 crankshaft rotation.
If the sensor is set incorrect then dwell times will be calculated incorrectly and you will get a extra spark event like a wasted spark system.

A max dwell time based on teeth varies based upon RPM and is calculated like this.

24teeth * 5500RPM = 132000 signal events per minute.

There are 60000 ms in a minute so:

132000/60000 = 2.2 signal events per ms

Invert this:

1/2.2 = 0.455.... or 1 tooth passes every 0.455ms at 5500rpm.

and with the first setting of max dwell at 6.0 teeth:

0.455ms * 6 = 2.73ms

Or the max dwell at 5500 is 2.73ms
----------------------------------------------------------
However doing this same math but with the wrong sensor set and it only seeing 12 teeth per cycle:

12teeth * 5500RPM = 66000 signal events per minute.

66000/60000 = 1.1 signal events per ms

1/1.1 = 0.909.... or 1 tooth passes every 0.909ms at 5500rpm.

and with the first setting of max dwell at 6.0 teeth:

0.909ms * 6 = 5.454ms

Or the max dwell at 5500 is 5.454ms, this is to long and would over drive the coils.

 

[Turbo Habanero]

Thanks Dirgle that was very helpful to in understnading how it works.

So you think the Sensor is set wrong is what your getting at?

my questions would be what sensor and how? Then how would i fix it or does it need to be fixed.


From what i've been reading there has been tons of people with this same issue as i.

 

[Dirgle]

Thanks Dirgle that was very helpful to in understnading how it works.

So you think the Sensor is set wrong is what your getting at?

It's just a working hypothesis based on a quick look over available information.

my questions would be what sensor and how? Then how would i fix it or does it need to be fixed.

The two sensors involved are the crank sensor(12 teeth) and a one of the cam sensors(1 sync tooth). I think the sensors are fine. It's probably just a setting in the ECU. Again this is just a hypothesis and action should not be taken without more info.

If you send me your base map I can take a quick look at it if you want.

 

[Turbo Habanero]

It's just a working hypothesis based on a quick look over available information.




The two sensors involved are the crank sensor(12 teeth) and a one of the cam sensors(1 sync tooth). I think the sensors are fine. It's probably just a setting in the ECU. Again this is just a hypothesis and action should not be taken without more info.

If you send me your base map I can take a quick look at it if you want.

okay will do all my sensors are also brand new