Thread: Crank, but no start after installing PnP EMS

I am putting my head on the chopping block but here it goes.

The vehicle is my friends 91' NX2000. Stock bluebird swapped vehicle. Has no issues starting when the stock ecu is plugged in.

Installed the EMS. Loaded the software for the AEM. Engine cranks, but will not start. It seems to be an issue with the AEM maybe not getting a good reading from the CAS. After reading a bit it looks like I need the 54mm CAS disc to get the vehicle running which I ordered.

So with the new CAS. disc installed will I run into the same problem with the ignition? Excuse me for such an extremely vague post, but I would like to know any easy things I could have missed before I install the disc, and try again.

you most likely have a sync issue. run over the install manual for the specific ems it will show you how to find the s tooth and time the car to fix that. it should start if its all wired correct and you changed the setting correct for the 24-1 wheel.

Is it possible to even get the car started with the stock disc?

yes. i am running my ve with the stock disk to 9k with very little issue.

Here is the info I found searching online for future reference. I will try this over the weekend, and hopefully I will have a running car!

This is the description of the problem of why it doesn't fire right up...

Nissan manufactures many different optical-type cam and crank sensors. These discs have different teeth patterns that, for the most part, are physically interchangeable with one another and can easily be installed upside down. If the vehicle has the stock cam/crank arrangement, the appropriate base map will SHOULD work and there are no adjustments needed. However, if the engine has been tampered with at some point and is not starting with the AEM EMS, check the parameter “Stat Sync’d”. If this parameter turns ON while cranking the engine, the cam/crank disc is correct and the starting problem lies elsewhere. If “Stat Sync’d” stay OFF while cranking, log the parameter “S Tooth”. Find a unique number here to synchronize from. In
other words, there should be at least one value displayed in the “S Tooth” parameter that only happens once per engine cycle (1 camshaft revolution). This value should be entered in the option “MX Sync Test”. Note: Some Nissan cam/crank sensors will have multiple unique values to sync from. If a change was necessary, be sure to confirm the ignition timing using the “Ignition Sync” option.

Apparently this is the procedure for finding this s tooth value...

what you need is a list of parameters up on the laptop. s tooth, engine speed, and what ever else you want. when you hit F6 it will log any and all the parameters you have in the list.

so setup your list.
hit F6
crank the car over for a bit
then hit F6 again to stop logging and it will prompt you to save the file.
open the log viewer and select the s tooth. look for the odd peak in the trace. curser over it and get the value.
insert that value in mx sync

You're on the right track. Let us know what happens. The car should at least start with the OEM CAS disc. I like to get it working with the OEM disc before going to the 24+1 disc to rule out other issues but you should be able to get this thing working regardless.

For info on what you're dealing with this thread is good, and specifically this post has the final number I needed: http://forum.aempower.com/forum/index.php/topic,25032.msg134626.html#msg134626
(You should instantly recognize what I'm talking about when I refer to the MS Word document.)

Alright I tried again today again and got the damn thing started! Here is what I did.

1. Logged S tooth while cranking engine for 10 seconds
2. Opened log file
3. Found the "odd spike" in the graph (which ended up being 88)
4. Entered "88" into MX Sync, and it fired right up

However...

It's running like it's on three cylinders. I didn't change the base map at all with the exception of the "mc sync" value. Ended up having to put the old ecu in so he could drive it. Of course it idled, and ran ok after installing the old ecu.

So. Anyone have some ideas for me to try?

What base calibration are you working with? An NX2000 base calibration or a Bluebird calibration?
What MAF (or are you using MAP+IAT?) and injectors is he using?
Did you try to set the ignition timing once you got the car started on the AEM?

I tried the g20 and bluebird calibration to start with.

We have 270 and 370 injectors both of which make no difference in how it runs.

He is using the stock maf at the moment. We should maybe try his Z32? Seems like we should be able to get it running on the stock maf though.

I didn't play with the ignition at all upon startup as my laptop battery died soon after starting the car.

You'll need to keep in mind that whatever calibration you use you will need to go through the MAF changing wizard and Injector changing wizard to make sure the calibration has the right settings for your MAF and injectors. Having the wrong settings for either could easily make it run like crap.

Once you have it starting and running however, it should be a piece of cake to get it running properly by making sure the MAF and injector settings are correct, and then changing fuel or timing (in the AEM maps) until you get a steady enough idle and then you can go through the real timing procedure.

Then you're off to the fun stuff.