1JZGTE with AEM V2 in MK2 Supra no injector pulse

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
Hi Everyone,

I'm installing a 1jz motor into my '84 Supra, running in mostly autocross events. Got the engine in, R154, 1 piece driveshaft, and wired in the AEM EMS V2 from Driftmotion. My frustration is that there seems to be no injector activity. I verified the black/orange wire going to each injector connector has 12v, and I have spark as demonstrated by cranking the motor over with a coil pack and spark plugs out of the head.

Checked the wiring and each of the injector pins of the AEM ecu go to a pair of injector ground wires (a pair of white/red, pair of yellow, and pair of white). The grounds from the AEM ecu seem fine, checking them with an ohm meter. I'm not positive, but is seems each injector ground wire from the ECU is not grounding in a pulse manner, so no fuel is being sprayed. Checking the spark plugs shows very dry, no fuel residue or wetness.

These are my thoughts:

The AEM is not pulsing a ground as each injector should fire. What could cause the ECU not to trigger each injector? I removed the ISCV, and the Traction Control unit, and VSV valve for the power steering. These connectors are just dangling at the moment. Do I need to short any of them out, if they are causing a no fuel condition?

Maybe the grounding injector wires from the ECU are not going to each injector. Although the wiring by DM looks correct, and the color of the wires from the ECU match up with the colors of the wires at the injector connectors. I'm assuming the wires are conducting, but I may go check that.

What other condition might stop the ECU from firing each injector? Motor just turns over, no indication it is close to starting. So I REALLY need some assistance on this as I'm running out of ideas. If there were a shop here in Northern Calif, I would haul the car over and let someone else finish this uber slow moving project!

I'd APPRECIATE any and all suggestions and ideas! Thanks!

Don
 

JAMDUN17

New Member
Aug 1, 2011
60
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Germantown MD
Check your cam sensor and be sure you have the proper one (cam 1) hooked up as this is the main one. I also had a problem with injectors firing as well when i didnt have any fuel running threw it, the node light wouldnt trigger when i turned over the motor but once i turn on the fuel pump they started to pulse so you could start there.
Those connectors wont have any effect on injector pulses, have you checked what type of sensors the AEM unit needs as some stand alone system require Hall effect sensors. Just a start, im sure DM and AEM would also be a good amount of help if you write to them as well.
 

525gte

New Member
Sep 19, 2011
450
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hoquiam
I did not see in your post what injectors are u running ? If I rember the aem u have will only run high impednce I.njetors
 

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
I'm running the deka 680cc high imp injectors from DM, and using the AEM 30-6050 honda ems modified by DM for the 1JZ. The adapter harness from DM makes sense, transferring all the essential wires from the 1JZ 34 pin ecu plug and the 22 pin ecu plug. I have the 4 row style of plugs for the ecu harness.

Since I am getting spark, I understand that means the crank sensor and cam sensor is working? If the cam sensor is not working, is there a way to see that on AEM Tuner screen? DM was patient and has been very helpful for many of my questions, but for the AEM EMS they said with 12V power to the coils and injectors, and the correct grounds, and batt, b+, Ig-swit wired correctly then motor should fire up. Well, not quite, not yet for me anyway.

It just seems like the AEM EMS is missing something, maybe a ground wire for the ECU, or maybe an open circuit somewhere. This diagnosing is challenging!

I need a local guru!
 

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
The DM adapter harness for the AEM uses the cam position sensor at terminals G2+ and G2-. This corresponds to pin # 60 & 61 in the 22pin connector to the ECU. (I have a 4 row ECU style). Today I followed each of the injector wires from the ECU to the injectors, checking continuity with an ohmmeter. The 3 wires coming out from the ECU tested fine to the injectors. Each wire would fire 2 injectors. I even ground one of the wires from the ECU to the injectors, while providing 12V to the other side of the injector, just to hear the injector click. Yes, it was a nice sound! Maybe I will hear it while the engine is running....someday....hopefully soon :)

Tomorrow I will test the resistance of the cam position sensors. Not much else for me to test. Any other suggestions would be greatly appreciated!

Don
 

Radial

New Member
Aug 20, 2011
252
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0
Norway
You probably have done it, but re-check the injector output settings.... Sounds like something is missing there, as the stock AEM Honda settings gives plenty of headroom for incorrect settings on an 1JZ.

a bone stock 1jz also fires all injectors at the same time...and a stock 2JZ fires individualy. Not that it has that mutch to say on an aftermarket setup, but its nice to have in mind.

Here are the stock honda settings;
# Injectors: 4
Factory Injectors: 190-290cc/min Saturated
Factory Inj Resistors: No
Injection Mode: Sequential


Stock available Injector drivers?
General purpose LS outputs : 12
General purpose HS outputs : 4


Also... most aftermarked ecu's have light indications for active Injector and Ignition driver activity... a nice way to check for actual activity on the outputs.
 

soapra

Supramania Contributor
Apr 6, 2005
860
0
0
VVTi'n, CA
www.kaizenmotorsport.com
You should ask Aaron how to pulse the injector outputs from the AEM EMS. Alternatively call AEM and have a tech show you how to do it. That would be what I would do. Call AEM , they made the box.
 

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
Well, Aaron at DM sells the AEM unit with a pre-loaded starter map. Enough to get it started, and I don't doubt that. However, with no injector pulse I can't really say the starter map is good or bad. Not there yet. I have a day off tomorrow, and Aaron suggested I data long a cranking session and send it to him. Now I just have to figure out how to do that.

I'm kind of a instruction manual type of guy. The AEM EMS doesn't really have a user manual regarding all the features or wiring info for the unit. The AEM Tuner program is even harder for me to understand. There must be a "how to" guide somewhere on the various tabs, functions of the Tuner program. I gotta find it. I just don't want to mess up Aarons initial program settings by clicking around the Tuner program w/o knowing stuff.

I think I'll check the cam sensor resistance and wiring continuity. I can handle that :)
 

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
Well, pretty much everything that I can understand seems to check out ok. The EMS is trying to send pulses out, but according to AEM tech there must be some issue that causes it to stop. The cam/crank/and TPS sensors seem to check ok. Aaron at DM offered to check out the AEM unit, and send it to AEM if needed. I appreciate his efforts. Hopefully they find a simple issue that can be quickly corrected. Looking back to the AEM install, it really wasn't that complicated, and in theory should be pretty easy, with some simple directions regarding body harness taps. The adapter harness connects to 2 of the stock 1jz engine harness plugs, and that mostly controls the engine functions. Just a matter of finding some sources of 12v power to connect up to the adapter harness. Could be a 1 hr job, and a running 1jz.....but not for me :(
 

bigaaron

Supramania Contributor
Apr 12, 2005
4,692
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Pomona, CA
www.driftmotion.com
I believe this one came back, got bench tested at AEM and had no problems at all, and then I even plugged it into a car at our shop and it fired up and ran excellent with no issues. I called him when it was running to say it ran fine.

I just want to clarify that our 1JZ AEM standalone and harness works just fine, and the problem is in his engine harness or wiring that was done swapping the engine into his car.

If you are in Fremont, throw the car on the trailer and bring it down here and we'll get it running.
 

bigaaron

Supramania Contributor
Apr 12, 2005
4,692
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Pomona, CA
www.driftmotion.com
I also want to add that any standalone will require a bit of previous knowledge and experience, and a properly wired engine harness. If the engine harness isn't wired correctly or there is a problem with injectors or sensors, the stock engine wiring diagrams will be all that is needed to figure it out. Reverse engineering my adapter harness isn't needed (which is why diagrams aren't included, because I would like to inspect it myself if there is potentially a problem). I mean no disrespect, but I was reading the previous posts and it kind of made it sound like the issues he was having were something caused by the unit he purchased from me, which is not the case. I have shipped these literally around the world to customers now with very few issues, which is an accomplishment because all standalones are a little bit beyond some people's experience level to set up and tune. We have also installed and tuned these on at least 10 local customer's cars, and that have all went well.
 

toy4speed

Member
May 18, 2011
40
0
6
Fremont, CA
Thanks for you help in checking out the AEM unit and harness Aaron. Great service, and no doubt a good product. It was never my intention to imply that there was anything defective with the AEM kit. I thought it was fairly clear that I was simply asking for forum advice, suggestions on what issues to look for in getting my engine started. You are absolutely correct in stating that some experience and knowledge is needed to install this standalone, and perhaps on that front I fell short. Certainly in diagnosing what was wrong with my wiring, I couldn't find the issue. Here is where some info either on-line, or from a person's previous install would have been helpful. Otherwise guys like me are just learning as we go. I had hoped to put together a somewhat detailed install guide, and I definely learned a lot along the way, so others may have an easier time. As it is, I'm leaving this as a unsolved mystery. The kit from Aaron at DM is simple as can be, plug into a stock 1jz engine harness, find a few sources of +12v switched power, and hope your stock sensors and harness are good.

One thing I learned from this install, is that many factors can ultimately cause something as simple as injectors to not fire. In discussions with AEM, it could be poor signals from the TPS, CPS, Cam sensors, poor grounds, maybe even AIT or WT sensors. Its a 25 yr (approx) engine harness, maybe wire continuity is broken somewhere, or I wired one of the half dozen wires wrong, regardless of reason, and I do not believe it has anything to do with the DM kit, I still have the utmost respect for Aaron and Driftmotion for not only supporting our cars and hobbies, but also backing up their products.

Don