Crazy Weird AEM ems SR20 problem - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

rbrixe1 · 07-08-2010, 09:28 PM

I have yet to get my sr20 going again. I did a turbo and fuel upgrade and then was advised by T1 to change from my Power fc to AEM ems. So I installed a series 1 ems along with 5bar map sensor and a iat sensor. I been having some ignition timing issues that I believe I have figured out. But of course some more bull shit has occured.
Problem: With the igintion in the on position my car and the laptop says that the engine is spinning at 600rpms!!!! Paratmeters on the aem pro say that the crank tooth, s tooth, fuel tooth, all that is changing like it is running. There is no spark occuring but it will spark if I actually do turn the motor over. Also no injector spray occurs unless I actually spin it over. I am baffled.
Aem says that it is just a loose ground that I must of did a shabby job when I wired the MAP and IAT sensors. They say just unplug them and should clear up. Did not work. They swear that the computer is fine.
So I call my wiring company (Wiring Specialities) and told them the deal and that I want them to check out my harness and redo what I did. Says he will but he believes that it is not a wiring problem.
Forgot to mention that this gradually happened. It started that sometimes after I spun the motor over it would say it was still spinning when it was not. I would cut the key off and wait a second cut it back on and all would be good.
Any ideas would be greatly apreciated.

rbrixe1 · 07-09-2010, 08:40 AM

Anybody? I need some help guys. Atleast some ideas for where I should be looking.

slociv · 07-10-2010, 08:58 AM

First you should have stuck with the power fc...

Some models of AEM require are new internal timing disk from AEM for the CAS sensor. The disk is located inside the CAS, basically it changes the timing so the AEM can properly read it.

Good luck, go back to Power fc, I've installed about 20 power fc, power ranging from 330 to over 500 and never had any issues.

j87w · 07-10-2010, 10:02 PM

Quote:

Originally Posted by slociv

First you should have stuck with the power fc...

Some models of AEM require are new internal timing disk from AEM for the CAS sensor. The disk is located inside the CAS, basically it changes the timing so the AEM can properly read it.

Good luck, go back to Power fc, I've installed about 20 power fc, power ranging from 330 to over 500 and never had any issues.

The only issues people have had that require the change of the CAS disc is high horsepower/high rpm timing changes. If you have this issue which most dont then you need to change your cas disc. If your cas disc is a problem it would show up in the high load/rpm range. If your changing it because your car will not start this is NOT the issue. Please dont spread misinformation. Theres nothing wrong with the AEM EMS when setup properly.

Nissan CAS disc

rbrixe1 · 07-12-2010, 02:57 PM

Thanks for the replies but I have the CAS disc problem solved. AEM helped me with that problem.
My problem is that the car and AEM pro say the engine is spinning ove at 600rpms when the key is just turned to the on position. The engine is not spinning!!!!
What could make it do that? Bad harness? Bad CAS? Or faulty ems box?
AEM says not the box. Yuri says it's not a wiring problem. What am I missing?

demon7983 · 09-11-2014, 03:44 PM

did u ever figure it out? my 240sx doing the same thing and i also have the aem cas disk installed. i also noticed that when i pulled the fuel pump fuse the rpm drops to 0. so tonite im going to check my fuel pump circuit to see whats going on?

splitfire · 09-17-2014, 08:15 AM

I had the same problem with Flex-o-lite fan controller and Series 2 AEM EMS. EMS was showing about 200-220 rpm when fans were running. Seems like current or voltage pulsations make EMS to misread engine rotation.

Kingtal0n · 09-17-2014, 11:31 AM

Check grounds, especially significant grounds coming off the ecu -> chassis.

07-08-2010, 09:28 PM	#1
rbrixe1 Leaky Injector Join Date: Apr 2009 Location: bastrop, la Age: 36 Posts: 89 Trader Rating: (3) Feedback Score: 3 reviews	Crazy Weird AEM ems SR20 problem I have yet to get my sr20 going again. I did a turbo and fuel upgrade and then was advised by T1 to change from my Power fc to AEM ems. So I installed a series 1 ems along with 5bar map sensor and a iat sensor. I been having some ignition timing issues that I believe I have figured out. But of course some more bull shit has occured. Problem: With the igintion in the on position my car and the laptop says that the engine is spinning at 600rpms!!!! Paratmeters on the aem pro say that the crank tooth, s tooth, fuel tooth, all that is changing like it is running. There is no spark occuring but it will spark if I actually do turn the motor over. Also no injector spray occurs unless I actually spin it over. I am baffled. Aem says that it is just a loose ground that I must of did a shabby job when I wired the MAP and IAT sensors. They say just unplug them and should clear up. Did not work. They swear that the computer is fine. So I call my wiring company (Wiring Specialities) and told them the deal and that I want them to check out my harness and redo what I did. Says he will but he believes that it is not a wiring problem. Forgot to mention that this gradually happened. It started that sometimes after I spun the motor over it would say it was still spinning when it was not. I would cut the key off and wait a second cut it back on and all would be good. Any ideas would be greatly apreciated.

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07-09-2010, 08:40 AM	#2
rbrixe1 Leaky Injector Join Date: Apr 2009 Location: bastrop, la Age: 36 Posts: 89 Trader Rating: (3) Feedback Score: 3 reviews	Anybody? I need some help guys. Atleast some ideas for where I should be looking.

07-10-2010, 08:58 AM	#3
slociv Join Date: Apr 2005 Location: ky Age: 39 Posts: 16 Trader Rating: (0) Feedback Score: 0 reviews	First you should have stuck with the power fc... Some models of AEM require are new internal timing disk from AEM for the CAS sensor. The disk is located inside the CAS, basically it changes the timing so the AEM can properly read it. Good luck, go back to Power fc, I've installed about 20 power fc, power ranging from 330 to over 500 and never had any issues.

07-12-2010, 02:57 PM	#5
rbrixe1 Leaky Injector Join Date: Apr 2009 Location: bastrop, la Age: 36 Posts: 89 Trader Rating: (3) Feedback Score: 3 reviews	Thanks for the replies but I have the CAS disc problem solved. AEM helped me with that problem. My problem is that the car and AEM pro say the engine is spinning ove at 600rpms when the key is just turned to the on position. The engine is not spinning!!!! What could make it do that? Bad harness? Bad CAS? Or faulty ems box? AEM says not the box. Yuri says it's not a wiring problem. What am I missing?

09-11-2014, 03:44 PM	#6
demon7983 Join Date: Feb 2012 Location: kansas Posts: 1 Trader Rating: (0) Feedback Score: 0 reviews	did u ever figure it out? my 240sx doing the same thing and i also have the aem cas disk installed. i also noticed that when i pulled the fuel pump fuse the rpm drops to 0. so tonite im going to check my fuel pump circuit to see whats going on?

09-17-2014, 08:15 AM	#7
splitfire Leaky Injector Join Date: Jan 2010 Location: KZ Age: 42 Posts: 58 Trader Rating: (0) Feedback Score: 0 reviews	I had the same problem with Flex-o-lite fan controller and Series 2 AEM EMS. EMS was showing about 200-220 rpm when fans were running. Seems like current or voltage pulsations make EMS to misread engine rotation.

09-17-2014, 11:31 AM	#8
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 38 Posts: 4,649 Trader Rating: (17) Feedback Score: 17 reviews	Check grounds, especially significant grounds coming off the ecu -> chassis.