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-   -   My 1995 can't pass inspection and runs terribly (https://www.miataturbo.net/general-miata-chat-9/my-1995-cant-pass-inspection-runs-terribly-60681/)

hustler 09-26-2011 10:07 PM

My 1995 can't pass inspection and runs terribly
 
I'm at a loss. I've done new plug wires, run a gallon of water through the intake plenum (carbon killer) and cleaned the EGR. I don't know where spark time is because the idiot who owned it before me put an under-drive pulley on it, but mechanical timing is right. When I retard timing to what looks like a normal range for the CAS, it misfires and is basically undrivable.

The car detonates, bad, and I know it's weak in #2. The idle is pretty much all over the place. Sometimes 1200rpm, sometimes 800, there is always a 400rpm drop with the AC.

I was 4x the limit on NOX and HC.

Also, when I put MS on this car, will it pass with no EGR?

Thanks for the help.

ScottFW 09-26-2011 10:57 PM


Originally Posted by hustler (Post 776171)
I don't know where spark time is because the idiot who owned it before me put an under-drive pulley on it, but mechanical timing is right.

I interpret this to mean the timing belt and cam pulleys are all properly aligned with both sets of cam lobes on #1 facing outwards at TDC? Just no mark on the pulley? I'd put a wood dowel down the #1 spark plug hole so you can see exactly where TDC is, make a little notch on that underdrive pulley by the 0 mark on the timing cover, then fire it up and set the timing without guessing.


When I retard timing to what looks like a normal range for the CAS, it misfires and is basically undrivable.
Mine did this exact same thing when the timing belt slipped a tooth. Might want to double-check that when the belt and cam sprockets all look aligned properly with 19 belt teeth between the sprockets, you should be able to rotate the crank 720* and still have everything lined up exactly the same. If it doesn't, you're off by one or more teeth.


The car detonates, bad, and I know it's weak in #2. The idle is pretty much all over the place. Sometimes 1200rpm, sometimes 800, there is always a 400rpm drop with the AC.
Possibly related to incorrect timing? Never had my idle this bad, can't say.


I was 4x the limit on NOX and HC.
Improper timing, misfires, bad cat can all cause this I think.


Also, when I put MS on this car, will it pass with no EGR?
Mine did. I mean, the EGR tube and valve are still on the car, but with the MAF unhooked from the stock ECU (my MS is in parallel) it's my understanding that EGR is rendered inoperative. Passed with flying colors on most aspects. Got close to the HC limit for the 25 mph portion, but I was datalogging the smog test and know it was running a little rich (low 14s AFR at 50-ish kPa), so I'll just pull a smidgen of fuel in that region for next time.

I'd start with the obvious- mark the crank pulley and get it timed properly, then go from there.


Thanks for the help.
:makeout::pitlab:

shuiend 09-26-2011 11:04 PM

Can you not swap back on a stock pulley instead of running the under drive one?

I would definitely check and see if the timing belt did jump any teeth.

As for EGR, is your car OBD1 or OBD2? If it is OBD1 you should be able to get it to pass fine with the engine swap.

hustler 09-26-2011 11:20 PM

OBD1. I'm relatively certain the crank and cams are in sync.

pusha 09-26-2011 11:56 PM

no friendly inspectors?

hustler 09-27-2011 12:09 AM


Originally Posted by pusha (Post 776216)
no friendly inspectors?

They're pretty hard to come by these days. I don't know what I'm going to do for the turbo car next year. I might have to put a cat in it and find someone who likes cars.

hustler 09-27-2011 01:25 AM

I may just say "fuck it" and get a Mariner like this one:
http://images.craigslist.org/5O35V05...b8c7801925.jpg

Reverant 09-27-2011 02:46 AM

Remove that underdrive POS pulley and put the stock back in, verify cam timing and 10* ignition timing.

curly 09-27-2011 03:36 AM

Could be a slipped pulley d/t a loose pulley bolt. Might wanna take it off and check the key way. You'll have to in order to put a stock pulley in, which you WILL do.

hustler 09-27-2011 08:08 AM

lol @ finding a stock pulley.

Fidgitk 09-27-2011 08:31 AM

Pull the plug on cyl 1
insert something long and skinny (screw driver, wooden dowel, piece of spaghetti, your dick) into spark plug hole
rotate engine while watching object to indicate tdc for cyl 1
make a mark on the pulley at the 0 degree mark on the timing indicator on the timing belt cover
attach timing light and verify timing

it'll at least get you in the ball park

hustler 09-27-2011 09:08 AM


Originally Posted by Fidgitk (Post 776308)
Pull the plug on cyl 1
insert something long and skinny (screw driver, wooden dowel, piece of spaghetti, your dick) into spark plug hole
rotate engine while watching object to indicate tdc for cyl 1
make a mark on the pulley at the 0 degree mark on the timing indicator on the timing belt cover
attach timing light and verify timing

it'll at least get you in the ball park

Done. I'm definitely not off a tooth.

pusha 09-27-2011 10:01 AM


Originally Posted by hustler (Post 776223)
They're pretty hard to come by these days. I don't know what I'm going to do for the turbo car next year. I might have to put a cat in it and find someone who likes cars.

I find it hard to believe, that in Texas of all places, you're having difficulty finding someone to help out a fellow white man.

y8s 09-27-2011 10:26 AM

I just want to give a shout out to all the assholes who complain about california's smog laws. fuck you very much.

hustler 09-27-2011 12:12 PM


Originally Posted by pusha (Post 776339)
I find it hard to believe, that in Texas of all places, you're having difficulty finding someone to help out a fellow white man.

I no speaky Spanish.

revlimiter 09-27-2011 12:43 PM

My 95 passes just fine with no EGR. I'd guess yours would too.

hustler 09-27-2011 09:07 PM

8 Attachment(s)
Can we all agree that mechanically its timed correctly?

revlimiter 09-27-2011 09:17 PM

Yup. That looks right to me.

hustler 09-27-2011 09:23 PM

Apparently this motor is fucked.

curly 09-27-2011 09:46 PM

What are the compression and leak down numbers? Oh, you haven't done it yet? Oh, you're wasting our time?


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