Go Back  Miata Turbo Forum - Boost cars, acquire cats. > Performance & Tuning > ECUs and Tuning > MEGAsquirt
Reload this Page >

VVT into a 95, MS3X built to Trubokitty specs - no start

MEGAsquirt A place to collectively sort out this megasquirt gizmo
Sponsored by:
Sponsored by:

VVT into a 95, MS3X built to Trubokitty specs - no start

 
Old 02-20-2019, 03:30 PM
  #1  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default VVT into a 95, MS3X built to Trubokitty specs - no start

So I’ve VVT swapped my 95 (3/94 build date) and had a friend build me a MS3X using www.trubokitty.com.

We’re running into a no-start issue right out of the gate… Engine cranks, has fuel and spark as verified by the occasional backfire (both out of the exhaust and intake tube) but we’re having trouble setting timing… It’s set to fixed and we’ve got the timing light on it but none of the changes being made in TunerStudio seem to have any effect, the timing marks are practically stationary…

I’ve tried to get a composite log because I understand that that’s step #1 for seeking help on here but I can’t even get that to work. I click the tab, start the log and nothing shows… What am I doing wrong? Everything Ive read makes it seem like it "just works" but I can't believe I can't find a how-to for it.

EDIT (2/22/19)

The engine is a junkyard NB2 that was pulled from a completely stock looking 2001 (IIRC). I've tried my best to follow Sav's Definitive 1990-1997 VVT Swap Megathread to the "t".

So the setup I've swapped into the car is:
Trubokitty guided MS3X build running the Trubokitty 01-05 basemap
NB2 longblock + original (looking) cam+crank sensors
NB2 trigger wheel (verified correct orientation, bump towards block)
NB2 Injectors
NB2 coils
NB1 Intake manifold
NB1 Throttle body
NB1 TPS
NB1 IACV
NA8 alternator
Radium fuel rail
Fuelab 545 AFPR
GM IAT
NA8 Racing Beat header
NA8 5 speed
Innovative LC2 (not currently wired in)
Custom built harness utilizing tons of Ballenger connectors

I've got the cam+crank angle sensors split off the original NA8 CAS plug (12v | GND | Signalx2).
VVT is pulling 12v from the custom CAS harness with it's signal wire running back to the MS3X center plug.
VICS is pulling 12v from the custom CAS harness with it's signal wire running back to the MS3X center plug (not currently wired in).
NB2 knock sensor (not currently wired in)

Current tune attached in post #15

Last edited by Stock; 02-23-2019 at 12:03 AM.
Stock is offline  
Old 02-20-2019, 09:15 PM
  #2  
Senior Member
 
Join Date: Apr 2017
Location: Greeley, CO
Posts: 602
Total Cats: 60
Default

Post your tune and a datalog trying to start
SpartanSV is online now  
Old 02-20-2019, 10:02 PM
  #3  
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,765
Total Cats: 676
Default

start the composite log, it'll ask you to name the file, name it something and click save. Then start cranking, continue for 5-10 seconds, then press stop.
curly is online now  
Old 02-20-2019, 11:12 PM
  #4  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

THANK YOU!

So I check the box to “capture log to file”, name it, start the log, crank for 10 seconds then stop the log?

Double checking because I’m dumb and this might help another dumb who’s searching later on...
Stock is offline  
Old 02-20-2019, 11:21 PM
  #5  
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,765
Total Cats: 676
Default

Yeah that should work
curly is online now  
Old 02-21-2019, 12:31 AM
  #6  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

Originally Posted by SpartanSV View Post
Post your tune and a datalog trying to start
Sorry, didn't see this. I'm on Brain's 01-05 base map.
Stock is offline  
Old 02-21-2019, 12:35 AM
  #7  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

So I tried a composite log per the above instructions, didn't see any sort of activity on the righthand side of the screen but I'm trying to upload using MT attachments feature and it keeps failing?

Stock is offline  
Old 02-22-2019, 02:30 AM
  #8  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

So when the file is 0kb then MT gives you an error when trying to upload...

I've captured 4 logs today, at least 10 seconds of cranking for each and one of them is 0kb, the other three being 1kb. Obviously this isn't correct so my question is: Am I supposed to be selecting certain gauges in the left-hand portion of the composite logger screen to display the cam and crank sensors pulses or did I potentially discover my no start issue in that the sensors not functioning at all?
Attached Files
File Type: csv
2019-02-21_23.51.22.csv (143 Bytes, 7 views)
Stock is offline  
Old 02-22-2019, 02:42 AM
  #9  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

Stock is offline  
Old 02-22-2019, 02:34 PM
  #10  
Junior Member
 
Join Date: Aug 2006
Location: UK
Posts: 128
Total Cats: 10
Default

Something to try in the mean time - check that you haven't got your coil packs swapped round.

I had similar when I first started up my VVT conversion - it would crank but not start, occasional backfires etc - I had spark, fuel and RPM readout just the same as you. I think it was an adaptronic triggering difference between NA and NBB triggering (as that's what ECU I was running at the time) but swapping the connectors of the coil packs round fixed it and it started up fine.

When I swapped from Adaptronic to MS3 I had exactly the same issue, but swapping them back to what they should have been originally solved it.
jonboy is offline  
Old 02-22-2019, 02:40 PM
  #11  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

Originally Posted by jonboy View Post
Something to try in the mean time - check that you haven't got your coil packs swapped round.

I had similar when I first started up my VVT conversion - it would crank but not start, occasional backfires etc - I had spark, fuel and RPM readout just the same as you. I think it was an adaptronic triggering difference between NA and NBB triggering (as that's what ECU I was running at the time) but swapping the connectors of the coil packs round fixed it and it started up fine.

When I swapped from Adaptronic to MS3 I had exactly the same issue, but swapping them back to what they should have been originally solved it.
I appreciate the input! I need to compile a list of items I've checked but the coilpacks are one of them, we've swapped them back and forth several times and check their wiring. I'm at the point now where I tore the engine down a few nights ago just to re-verify timing marks on cams+crank.
Stock is offline  
Old 02-22-2019, 02:45 PM
  #12  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

I'm just feeling around in the dark here, obviously... On the composite logging tab I selected "Tooth Logger" because hey, why not?

For the first time ever I saw activity on the screen (right-hand side) but I don't know if it's the information I'm looking for. Anyways, I've attached it.
Attached Files
File Type: csv
2019-02-22_12.32.43.csv (63.1 KB, 9 views)
Stock is offline  
Old 02-22-2019, 02:48 PM
  #13  
Junior Member
 
Join Date: Aug 2006
Location: UK
Posts: 128
Total Cats: 10
Default

Just to be clear I was suggesting plugging coil pack 'A' connector into pack 'B' and vice versa, leaving the plug wires in the right place (or swap the plug wires round to achieve the same thing) - not sure if I explained myself too well,

It drove me nuts trying to figure out why it was firing but at completely the wrong point, spent ages head scratching trying to work what it was thinking it was a software / sensor / user error when it was really something simple (and not my fault!)
jonboy is offline  
Old 02-22-2019, 02:52 PM
  #14  
Junior Member
 
Join Date: Aug 2006
Location: UK
Posts: 128
Total Cats: 10
Default

It might also be worth listing out the basics:

What triggering are you using - standard NBB crank / cam sensor & crank trigger wheel?

How did you wire it up - existing wiring, run new wires etc? Which inputs are they connected to on the MS3?

Then post your MSQ file and someone can check it's configured correctly..
jonboy is offline  
Old 02-22-2019, 11:38 PM
  #15  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

The engine is a junkyard NB2 that was pulled from a completely stock looking 2001 (IIRC). I've tried my best to follow Sav's Definitive 1990-1997 VVT Swap Megathread to the "t".

So the setup I've swapped into the car is:
Trubokitty guided MS3X build running the Trubokitty 01-05 basemap
NB2 longblock + original (looking) cam+crank sensors
NB2 trigger wheel (verified correct orientation, bump towards block)
NB2 Injectors
NB2 coils
NB1 Intake manifold
NB1 Throttle body
NB1 TPS
NB1 IACV
NA8 alternator
Radium fuel rail
Fuelab 545 AFPR
GM IAT
NA8 Racing Beat header
NA8 5 speed
Innovative LC2 (not currently wired in)
Custom built harness utilizing tons of Ballenger connectors

I've got the cam+crank angle sensors split off the original NA8 CAS plug (12v | GND | Signalx2).
VVT is pulling 12v from the custom CAS harness with it's signal wire running back to the MS3X center plug.
VICS is pulling 12v from the custom CAS harness with it's signal wire running back to the MS3X center plug (not currently wired in).
NB2 knock sensor (not currently wired in)

Attached current tune below.
Attached Files
File Type: msq
CurrentTune.msq (296.9 KB, 24 views)

Last edited by Stock; 02-23-2019 at 12:02 AM.
Stock is offline  
Old 02-23-2019, 07:26 AM
  #16  
Moderator
iTrader: (12)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 18,910
Total Cats: 2,364
Default

Check rising edge versus falling edge timing. Grasping at straws here but switching from one Rev built MS3 to another one and they required different settings because he switched from one decoder to another type. I didn't know until it wouldn't start. Maybe there's been a decoder change somewhere along the line.
sixshooter is offline  
Old 02-23-2019, 10:42 AM
  #17  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

Originally Posted by sixshooter View Post
Check rising edge versus falling edge timing. Grasping at straws here but switching from one Rev built MS3 to another one and they required different settings because he switched from one decoder to another type. I didn't know until it wouldn't start. Maybe there's been a decoder change somewhere along the line.
We’ve flipped that switch several times. No noticeable change. :(
Stock is offline  
Old 02-25-2019, 05:46 PM
  #18  
Junior Member
Thread Starter
 
Join Date: Apr 2011
Location: Las Cruces, NM
Posts: 351
Total Cats: 29
Default

So aside from a composite log, is there another way to verify that the cam/crank sensors are functioning as they should?
Stock is offline  
Old 02-25-2019, 06:47 PM
  #19  
Elite Member
iTrader: (15)
 
Join Date: Oct 2006
Location: Las Cruces, NM
Posts: 1,517
Total Cats: 400
Default

Just a heads up. I'm helping him out with his MS install. I built it using the Trubokitty instructions (Thanks Brain!). I flashed the firmware and loaded the base tune. I calibrated TPS, set up wideband settings and thermistor tables for air and coolant. Timing offset has been difficult to set. As Stock mentioned, he set up wiring according to Savington's VVT swap thread. I loaded 1.5 firmware and used settings from Trubokitty base tune. I'll try to make a composite log asap. Note: we do get trigger pulses when we try to set base timing with a timing light, but they are off. Setting offset has little or no effect. We do have fuel and spark.
99mx5 is offline  
Old 02-25-2019, 07:03 PM
  #20  
Senior Member
 
Join Date: May 2007
Location: Atlanta
Posts: 657
Total Cats: 104
Default

That crank sounds real slow.

And while you have fuel and spark, could really use a log file to tell if you're getting sync or not. Just because it's triggering doesn't mean it's synced.

And something simple to check - since you're getting flames out the intake - put your hand over the exhaust and crank. Is the exhaust sucking in? If so you've got the cam's facing the wrong way.
gooflophaze is offline  

Thread Tools
Search this Thread
Quick Reply: VVT into a 95, MS3X built to Trubokitty specs - no start


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.