2000 Miata won't start after head gasket change
 

Overheated Miata but it still ran sorta OK. No real compression. Pulled head and had it professionally rebuilt. Reinstalled head and now car cranks fine but won't even try to start. Ran scanner on it and it gives a P1345 code. Looked up code and it seems to indicate a bad camshaft position sensor or a diagreement between camshaft position and crankshaft position.

Should I just replace the cam sensor or how would you approach the problem?

Thanks.

Post pictures of the crank at TDC (I want to see the mark on the cog lined up with mark on the engine), Then post a picture of the 2 cam gears, then a picture of the front 2 cam lobes. This way we can verify timing is correct.

if the cam sensor wasn't bad before, what makes you think it is now?

dont you think the most logic thought is you forgot to hook you cam sensor back up? or did the timing belt wrong?

P1345 says something is wrong with cam sensor.

did you plug it back in?


I know this is crazy, but im assuming you unplugged it to remove the head.

Couldn"t send pictures using this forum. ????? I sent email to moderator for another method. I think the cam/belt alignment is fine. Another source said to check the two outside connectors inside the power side of the cam sensor cable with key on. He said I should see 10.5 volts DC. I don't get any voltage. Seems like cam position sensor isn't being powered. However, the pins are very small and trying to do it all myself, I may not have made good contact.

How do I post photos? I get a message about "token missing"?

tone ring is in the wrong orientation,

"Tone Ring" what the hell is that? I think I found my starting problem. I replaced the head with a used, but rebuilt head that I bought from a spec racer. One of this forum's members emailed me and asked about the "bumps" on the intake cam sprocket. I looked at mine and there are no bumps. I then looked at my original head and cam sprockets. Those sprockets have the bumps. I believe that the cam position sensor uses these bumps to determine cam position. I'll know for sure tomorrow after I change the sprockets.

So I figured out this is my Friend up near KC, he swapped some heads around but didn't keep cam sprockets with the block, only the heads.

So, long story short, there's no cam nubbins to trigger as he's got it together now. I expect it should work alright after swapping those back around.

Not sure if that'd be considered a tone ring, but that's a damn good guess blkmkiii...

Did he swap from a 94-97 head to the 99/00 head? Then keep the older cam gears? Those are just an odd thing not to swap, but would without a doubt cause the issue he is having.

I'm not entirely sure what's happened. His car is a 99 or 2000 and the head we swapped over was supposed to be a 99. The manifold fits, so it must be right...

I can't find the cam sprockets from the old protege 1.8 I bought from him though, I wonder if they didn't accidentally get switched at some point?

https://www.miataturbo.net/attachmen...ine=1458586797

https://www.miataturbo.net/attachmen...ine=1458586797

Oops, at least the intake manifold doesn't have to come off again :)

lol. important details you shouldn't leave out of posts:

:ne:

What are you rambling on about now? 94-97 heads do not bolt up to NB intake manifold....

Someone closer whack brain for me, he needs a reboot :fawk:

DEEZUMS fixed it! It runs great now. Thanks.

Problem was that I thought all sprockets were identical. Now the Intake sprocket has the "bumps", but I left the exhaust alone since the cam position sensor only looks at the Intake sprocket.

I'm pretty sure that the manifold will physically fit onto the head, but with the caveat that the ports don't line up.

This image is of an NA intake gasket on an NB head:

https://www.miataturbo.net/attachmen...ine=1458588945

Source: Project Miata Streetfighter: Vol 3 "Getting our Head straight"

Good to know, not something I've ever dealt with personally.

Glad to hear it's running again!