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SidVicious's Avatar
 
Join Date: Feb 2003
Location: Houston, TX
Posts: 295
Continuing emissions saga...

Remember this?

New:
Distributor cap & rotor
spark plugs and wires
fuel filter
fuel line
O2 sensor
changed oil
vacuum hoses
BOV
chips are stock

Removed the old cat today and I had a French cat (ie. NO GUTS!) I'm thinking - problem solved. Bolted the new one in, went for a 30 mile or so drive, and slid into the testing station somewhat confident.

You guessed it:

FAILED AGAIN!!!

Results:

25 mph test:

HC standard 168, reading 134 result PASS
CO standard 1.08 reading .40 result PASS
NOx standard 1208 reading 1196 result PASS (Whew!)

15 mph test:

HC standard 173 reading 184 result FAIL(geez it was 173 last time w/o cat)
CO standard 0.98 reading 0.69 result PASS
NOx standard 1323 reading 2659 result FAIL (WTF!?!)

Okay, I'm a little frustrated. At this point time is not critical. If I get stopped I carry all four failed test results with me. Hoping for sympathy from the cop.

What have I missed? I took the hard pipe off last week and really did a thorough cleaning of the throttle body and intake. I have no idea why I saw a reduction of 870 points off my 25 mph test yet only took off 32 points from the 15 mph test. And why did my HC go up? Makes NO sense.

Any suggestions? Copious amounts of loose gasoline and a couple marine flares have come to mind already. Grenades have a certain appeal...
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Old 04-26-2003, 07:47 PM
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Still could be a vacuum leak, HC's are just unburnt fuel exiting the tailpipe. You are over rich, either back the AFM off a few notches, or keep tracking down the leak.

Unless like FR stated you have a bad O2 sensor, even though it's on your list of replacement parts.
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Old 04-27-2003, 08:18 AM
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Sid, I just thought of something else I had a guy in my local PCA that was failing just like you were and he had a broken vacuum connection at the timing valve (cycling valve.) This thing gets really baked under the manifold and the little plastic nipple pieces just crack off, but they look like they are still connected.

I had to eventually bypass mine as I installed a MBC, and noticed that one of mine was in fact broken as well.
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Old 04-27-2003, 09:22 AM
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Yeah, the O2 sensor was the first thing I replaced.

I pulled the plugs last night. I had replaced the plugs with what was in there: Bosch W7DTC's. Since my spark might be too hot (a friend's suggestion), I replaced them with WR7DC's last night. Hey, plugs are cheap and I'm desperate. The ones I took out seemed equal in wear, what little there was. I can't find the temp range of either plug, but the WR7DC's are listed in the manual. Probably won't make a lick of a difference.

Scott, you're talking about that blue/black valve under cylinder 4 intake, right? When I unplugged the blue side just now, it sucked a little air. The black side was not super tight in the hose. Would that be enough? Should it hold a vacuum on the blue side? The car hasn't been run in a good 20 hours.

We have another PCA meeting a week from Monday. If I don't have this sorted by then I'll see what anyone there can suggest. I've finished repacking the CV joints on the passenger side, I have to lay it up this week and do the driver's side.

I haven't pulled the injectors yet. I think I'll go ahead and order the o-ring kit tomorrow and plan on pulling them. I have access to an ultrasonic cleaner. Has anyone else ever cleaned their injectors that way?

Should I order a new cycling valve too? Maybe it's old and not working properly? You should have seen the tear in the BOV when I took it off.

The PO obviously just did the minimum maintenance to get by. He had to have known about the cat. I wish there was recourse for something like that. Aside from finding him and punching his lights out. Don't think that hasn't crossed my mind.

Sorry about the vent. I'm not happy about this.
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Old 04-27-2003, 10:42 AM
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No if your timing valve was bad you would have some associated boost issues as well.

I am just trying to think of where you might have vacuum leaks that you may not be easily see. In additon there are two vacuum lines that run behind the head and into the passenger compartment that have hard plastic lines going to them, they can also become brittle and break.

Does everything with you're climate system work correctly, such as the heater valve, and the air vent selection controls?

Too aslso add with what FR was saying about yo're injectors, do have any miss fires? Even subtle ones? Any other driveability conditions that you can post, like rough idle, or hesitations?
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Old 04-27-2003, 12:53 PM
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Really no driveability issues at all. Idles smooth. Boost comes on like a kick in the back. Running temps are so consistant I could see the difference now that there's a cat stuffed in the pipe. dammit. Could tell the difference in acceleration too.

Climate control is alright. Heater control valve is about 8 months old.

I am stumped.

Now add this to my woes: Both cv joints on the driver's side need to be replaced. I got them apart tonight and don't like the looks of either of them. Both boots were intact, but I was doing it as preventative maintenance. Better to discover it in my garage than on the highway, but I'm beginning to wonder if I will ever get this car sorted out.

Rats.
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Old 04-27-2003, 09:13 PM
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