This is topic Failed smog, need advice in forum General Talk at Northern California Ford Owners  .


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Posted by stangin' (Member # 514) on :
 
My friend's 93 GT just failed smog yesterday so now we're in the process of trying to trace things down.

The car has your basic HCI setup and running through a bassani x-pipe. What's usually the culprit for high HC and NOx that we should look at? After it failed both the 15 and 25mph test, I asked the tech to try something so I took out the timing spout out. This made it pass HC, but NOx was still really high.




 

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Posted by SLOWSN95 (Member # 8269) on :
 
Looks like it's running lean. Call the BAR. They will help you out with the problem. That's what I did. The number should be on the smog test paper
 

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Posted by iceman302 (Member # 7180) on :
 
Check vacuum lines. Check the fuel pressure regulator. Something is causing it to run lean to generate high NOx.
 

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Posted by theconductor (Member # 13458) on :
 
Does Bassani make a CA legal x-pipe?
 

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Posted by FiveOhChuck (Member # 12588) on :
 

quote:

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Originally posted by theconductor:
Does Bassani make a CA legal x-pipe?

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quote:

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Originally posted by TEXAS:
Neight

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I sell strawberries now bro. Check me out in my hustle under my avatar.
 

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Posted by stangin' (Member # 514) on :
 
thanks guys, i'll look into this lean issue more.

neight, quit selling those strawberries and get you stuff back from Dan.
 

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Posted by MaK_1967v8 (Member # 12187) on :
 

quote:

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Originally posted by FiveOhChuck:

quote:

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Originally posted by theconductor:
Does Bassani make a CA legal x-pipe?

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No x-pipe is ca legal

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quote:

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Originally posted by MaK_1967v8:

quote:

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Originally posted by FiveOhChuck:

quote:

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Originally posted by theconductor:
Does Bassani make a CA legal x-pipe?

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No x-pipe is ca legal

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Not exactly correct information. Magnaflow sells a smog legal X pipe. ( 4 stock OEM replacement cats with their typical X pipe in the center ) But its also a pretty penny. ( stainless steel piping combined with magnaflows overpriced shenanigans )

your best bet is to simply track down a stock H pipe.

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running lean isn't a cat issue.
 

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Posted by SacStangDriver (Member # 8304) on :
 
nox deals with EGR andlean conditions. i'd check egr system first.
 

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Posted by FivePTSlow (Member # 7682) on :
 
If your nox reading is that high I can guarantee you one thing. You need cats. You can have a completely inoperative egr system with good cats your nox will not be anywhere near those numbers.

I've been down this road very recently. Had to buy new cats. I tried everything else first. New vacuum hoses everywhere, new egr valve, new egr vacuum solenoid, full tune up(spark plugs/wires, o2 sensors etc), all new fluids, pull timing spout, retard timing, PCV valve, so on and so on. All of that did nothing to reduce my emissions. My car was failing only nox, passed everything else. Once the cats were replaced my nox emissions dropped to nearly 0 ppm
 

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Posted by stangin' (Member # 514) on :
 
I still haven't had much time to mess with the car, but today I ran a code scan.

KOEO - passed
KOER - 91 and 12, 13 for high rpm idle.

There's no check engine light on normal driving. Can a bad o2 sensor make the car fail this bad?

I also noticed on the car that there's no vacuum hose on the AFRP . The port is just left open. How does this affect performance? Where should the hose off the FPR be connected to?
 

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Posted by iceman302 (Member # 7180) on :
 
The missing vacuum line to the FPR would definitely cause the symptoms you've mentioned. It's been a few years since I've worked on a Fox but the vacuum line for the FPR is a short, fitted line that runs to the vacuum "tree" on the back of the upper intake manifold.

After fixing that, I'd verify that the other vacuum lines are run properly... especially to the EGR solenoid. Hope that helps.
 

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