CA Smog Fun! (But Not Really)

94GTCoupe

10 Year Member
May 7, 2006
1,412
91
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CA
Car:
94 Mustang GT 5 Speed.
BBK Headers
Gt40 Tubular Intake
Factory converters (known good)
Timing 10º BTDC (Spout Out, advances when in)
Plugs, wires, ect all good
No codes, or check engine light
Passes KOEO, KOER and Cylinder Balance Test
Car runs perfect.

First test;
EMISSIONS PASS
VISUAL FAIL

BBK FPR not legal (my fault, should have changed it.
Intake manifold not legal (told them it was factory that I painted, problem solved)

20130305_130739.jpg


Ok, go home and throw the stock fpr (been sitting in a box for over a year) back on and retest.

VISUAL PASS
EMISSIONS FAIL

High NO at 25 mph

20130305_130728.jpg


So my question;
Bad FPR?

I've not had a chance to check fuel pressure yet.
Had to get to work.
 
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Wow, bad luck on the visual inspection. I had a smog guy give me a hard time about a painted part once, and he completely missed the shiny red Aeromotive fpr I had at that time. Unless you run into someone who actually knows mustangs, having a clean and painted engine bay makes you suspicious. :(
 
Yeah, the first shop I went to, on Sals recommendation (thanks Sal!, haha) about had a heart attack when he looked under the hood.
Said I needed carb numbers for headers (plainly visible) coil (again, plainly visible) dizzy cap (what?) intake manifold (its a factory part) and said I HAVE TO see the referee.

Ok, update.

Rented a fuel pressure gauge last night.
Couldn't get a reliable reading, due to bad seals in the fittings (thanks AutoZone).
The one reading I got was 30lbs at idle with vacuum, without vacuum at idle it SLOWLY rose to just under 40lbs.
That was the only reading I could get.

So we swapped out mine for Sals, which is known good.

This morning I cleared and reset the computer, backed timing up to 8º BTDC 1/4 tank of premium and a bottle of octane booster.

Took a drive on the freeway and straight to test.
Well what do you know, it passed!
20130306_104150.jpg


still suspect it was a bad fpr so I'll be buying a fuel pressure gauge and checking it out later.
In the mean time, I'll be putting my BBK fpr back on.

Again, thanks a lot for the help Sal!
 

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hey davis3, i know you passed the emissions test already but did you ever figure out the reason as to why you didnt pass? was it a bad fpr? did you ever consider that it might have been your timing was off? you went from not passing with 10*, to passing with 8.
 
Based on everything you've mentioned about the FPR, I would guess that the rail pressure was low and you were running lean. Lean conditions will result in high NOx emissions due to the extra oxygen. Backing the timing down a bit can sometimes help because NOx formation during combustion is a combination of pressure and temeprature, however temperature and extra O2 are the most significant factors. I'm glad you got it resolved. Those CA inspections don't sound fun!
 
Timimg shouldnt of caused you to fail. I passed CA smog at 14 degrees and same for NJ emissions this year

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Timing can definately cause you to fail. Pulling the spout to get a 5.0 to pass is one of the oldest tricks in the books.

Kurt
 
I still say it might have been your timing.. Reason being?? Timing controls at what point the combustion in your engine is ignited. More timing= combustion being created faster= more emissions. FWIW I know for a FACT that the stock timing should be 8*. Anyone please correct me if I'm wrong! Just a 20 year old kid who's new to the mustang scene..
Chaos254 if you're passing in CA at 14* let me get that hook up!! haha..
 
Base timing is 10º btdc from the factory.
I only backed it off just to be safe.

It wasn't the timing in my case, as the only thing that changed between the pass and fail was the fpr.

Don't know what else to tell you :shrug:
 
In my case (2 weeks ago) they came out with a timing light and pulled the spout to verify I was running factory timing. If its not its an automatic fail. Funny how they don't all check the same things.
 
In my case (2 weeks ago) they came out with a timing light and pulled the spout to verify I was running factory timing. If its not its an automatic fail. Funny how they don't all check the same things.

Wow. I've never had a smog guy check my timing here in SoCal, ever. You must have gone to someone who was really strict.