Notices
General Miata Chat A place to talk about anything Miata

NB2 Won't Start After Timing Belt

Thread Tools
 
Search this Thread
 
Old Nov 18, 2015 | 03:36 PM
  #21  
shuiend's Avatar
mkturbo.com
iTrader: (24)
 
Joined: May 2006
Posts: 15,235
Total Cats: 1,700
From: Charleston SC
Default

Originally Posted by Ncorlis
Hey everyone, I appologize for the wait. Here is what the timing belt looks like right now. This is the exact position of the belt that caused the car to not run. Or, at least I think it caused it to not run. Does it look ok? I'll use that video's tooth counting method to check.



Post a picture of looking at the head from the front. I want to see the front cam lobes on both cams.
Old Nov 18, 2015 | 03:37 PM
  #22  
2ndGearRubber's Avatar
Senior Member
 
Joined: Nov 2010
Posts: 1,183
Total Cats: 18
From: Pittsburgh PA
Default

^ I would have said the exhaust, but I agree in principle.
Old Nov 18, 2015 | 03:56 PM
  #23  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

Thank you everyone. Looking at it now, maybe the exhaust cam is a tooth too low.



Top of cylinder 1





Exhaust side





Intake side





Top view
Attached Thumbnails NB2 Won't Start After Timing Belt-80-20151118_144840_007d62fb8d6e29dbc0b0e9ef17ba1d8df33e12e1.jpg   NB2 Won't Start After Timing Belt-80-20151118_144856_af3877c1a45b6757446dc9e12ac47385854ce59e.jpg   NB2 Won't Start After Timing Belt-80-20151118_144909_475714f2f03b09f90e4c7e46b85341a5bd29ac8b.jpg   NB2 Won't Start After Timing Belt-80-20151118_144919_d79f61ad588050ba97d47de85121f32252d94c08.jpg  
Old Nov 18, 2015 | 04:15 PM
  #24  
aidandj's Avatar
SADFab Destructive Testing Engineer
iTrader: (5)
 
Joined: Apr 2014
Posts: 18,643
Total Cats: 1,870
From: Beaverton, USA
Default

Cam lobes are correct. I don't see anything wrong with that.

What about clearance on the crank sensor? Did it get moved? Is it too far away?
Old Nov 18, 2015 | 04:24 PM
  #25  
EErockMiata's Avatar
Senior Member
 
Joined: May 2011
Posts: 638
Total Cats: 76
Default

any missing grounds? are the plugs wet after cranking?
Old Nov 18, 2015 | 07:21 PM
  #26  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

Hmm.. No, there are no missing grounds. There weren't any before the timing belt was removed. This is why I am so confused. The car ran fine before I adjusted the timing belt, and now that I have pretty much been confirmed that it is not a timing issue, I have no idea what it could be.
Old Nov 18, 2015 | 07:25 PM
  #27  
good2go's Avatar
Elite Member
iTrader: (2)
 
Joined: Dec 2011
Posts: 2,815
Total Cats: 1,237
Default

Originally Posted by Ncorlis
Hmm.. No, there are no missing grounds. There weren't any before the timing belt was removed. This is why I am so confused. The car ran fine before I adjusted the timing belt, and now that I have pretty much been confirmed that it is not a timing issue, I have no idea what it could be.
Is the crank trigger wheel on backwards? (Sav's original #3)
Should be convex side toward the radiator.

Last edited by good2go; Nov 18, 2015 at 08:06 PM.
Old Nov 18, 2015 | 10:48 PM
  #28  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

Nope, the crank trigger wheel wasn't removed from before. I honestly have no idea. I wonder if maybe exhaust cam is off a tooth, or maybe I had the crank sensor too close.
Old Nov 19, 2015 | 01:31 AM
  #29  
codrus's Avatar
Elite Member
 
Joined: Mar 2007
Posts: 5,298
Total Cats: 884
From: Santa Clara, CA
Default

My impression is that being off one tooth won't prevent it from starting. It may stumble and idle poorly, or it may have no top end (depending on which way you're off), but it will start.

I agree that the most likely cause is electronics. Do you have a stock ECU, or aftermarket? If aftermarket, many of those have cam/crank pulse debugging tools. If it's a stock ECU, you might be able to hook up an OBD2 scanner and see if it outputs an RPM value while cranking (not sure if the stock ECU does or not). If you get an RPM signal, you know the cam/crank pulses are good.

You say you think you smell gas -- do you actually? If so, then your cam/crank signals are good (ECU won't inject fuel without a sync) and that would suggest it's probably a spark problem.

Stupid question, but you did get the plug wires back on the right cylinders, right?

On the "missing ground" topic, the main ECU harness is grounded through a bolt at the front of the intake manifold. The harnesses are somewhat in the way for the timing covers, so it's not unusual to take that bolt out to get more flexibility in the harness, and if you forgot to put it back on, or missed one of the ring terminals that goes under it...

--Ian
Old Nov 19, 2015 | 03:06 AM
  #30  
Savington's Avatar
Former Vendor
iTrader: (31)
 
Joined: Nov 2006
Posts: 15,442
Total Cats: 2,106
From: Sunnyvale, CA
Default

OK, now replace your cam angle sensor
Old Nov 19, 2015 | 01:36 PM
  #31  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

Thank goodness I have a spare engine sitting around. I'll salvage a cam sensor from it after I put my engine back together and see if that fixes it.

Ian, thank you for a very intelligent and insightful answer. I love it when people explain things so thoroughly and in a "point A leads to B, which causes C" manner. I will test the spark after everything is buttoned back up.
Old Nov 25, 2015 | 07:24 AM
  #32  
TonyV's Avatar
Elite Member
iTrader: (17)
 
Joined: May 2007
Posts: 1,615
Total Cats: 2
From: NY
Default

Subscribed.... Facing same issues.
Old Nov 30, 2015 | 12:50 PM
  #33  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default Cam Angle Sensor didn't work

It still will just crank and crank without ever starting.
-timing is correct
-not crank sensor
-not cam angle sensor
Old Nov 30, 2015 | 01:32 PM
  #34  
NiklasFalk's Avatar
Senior Member
iTrader: (1)
 
Joined: Jun 2006
Posts: 1,391
Total Cats: 63
From: Sweden
Default

Known working sensors or just random ones believed to have worked at some time in the past?

Connectors or ECU?

Stupid stuff like a non-clicked connector can spoil a lot.
Old Nov 30, 2015 | 01:39 PM
  #35  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

The car literally ran absolutely fine before I removed the timing belt because it was too tight. I put the belt back on, and it won't start. I'll check the connectors, but I am pretty sure they are all clicked. The ECU hasn't been touched in a long time. All of the grounds are good too.
Old Nov 30, 2015 | 01:47 PM
  #36  
psyber_0ptix's Avatar
Elite Member
iTrader: (4)
 
Joined: Mar 2012
Posts: 4,648
Total Cats: 544
From: Northern VA
Default

Are you on the stock ECU by chance? Curious if a simple log would tell us what the computer sees. Check fuses?
Old Nov 30, 2015 | 02:02 PM
  #37  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

Yep, stock ECU unfortunately. I'll check the fuses in a second.
Old Nov 30, 2015 | 02:12 PM
  #38  
codrus's Avatar
Elite Member
 
Joined: Mar 2007
Posts: 5,298
Total Cats: 884
From: Santa Clara, CA
Default

99% of the time, if you took it apart and put it back together and it doesn't work, it's something you put back wrong.

Have you pulled the plugs? Is it injecting fuel? Is it sparking?

--Ian
Old Nov 30, 2015 | 02:20 PM
  #39  
psyber_0ptix's Avatar
Elite Member
iTrader: (4)
 
Joined: Mar 2012
Posts: 4,648
Total Cats: 544
From: Northern VA
Default

Output test mode would be so sexy right now
Old Dec 2, 2015 | 03:28 PM
  #40  
Ncorlis's Avatar
Thread Starter
Junior Member
 
Joined: Jan 2014
Posts: 117
Total Cats: 0
Default

I made a Youtube video showing what the car does when I crank it. I apologize for not being the smoothest talker in the world, and the lack of turbo



All times are GMT -4. The time now is 08:35 AM.