Fuel Injection Conv. can't pass CA. smog - any ideas, need advise

cant pass smog, despite new O2 >sensor and Cat. Conv. Anyone with similar problem, how did you fix it. Need advise.

Do you have the readings they got on your engine? This may help diagnose it.

Chris

how do your plugs look? recent tune-up done?

Don't know. I keep it tuned and it isn't a daily driver. Also I didn't that it for along drive after getting the Cat. Conv put it. Why does that seem to make a difference?

Yes, all reading were within normal range except the NOx @ 25mph, it has read from 1200 to 1530 . Everything else now passes. What do you think this means.

No, I did not. I drove it over city streets a few miles to the Smog Check Station. No one ever mentioned I needed to "break in the Cat." Why is that? Where is this type of information documented?

Has nothing to do with breakin. The 20 minutes is to insure that the cat actually is up to temp and in it's working range. Last summer I had to get an emissions check and had to let it sit outside for a couple of hours before we could get the bay open. Just for curiosity

- mine and the shop owner - we fired it up and ran the sniffer cold. Ran it around the neighbor hood for 15-20 minutes, tested again. Took it out on the freeway and ran it at 70-75 for about 30 miles then tested a third time. The cold check failed miserably, the light warmup helped a lot but it was still marginal. After the highway run, all readings were low to midrange. Convincing enough the make that a standard recommendation for that shop, especially for older vehicles.

If you can get a retest, take it out and run it on the freeway for at least 10-15 minutes so the engine is good and hot. Before you do this, fill the tank with something like Chevron premium.

Bone P.A. ( snipped-for-privacy@charter.net) wrote on Monday 24 May 2004 12:04 pm:

When I lived in the Chicago suburbs, the emissions letter they mailed explicitly said not to test with a cold engine, and to let your car warm up for at least 20 minutes. Of course, in Chicago traffic, it usually took at least 20 minutes to get anywhere.

High NOX is usually an indicator of an EGR valve not fucntioning, plugged egr passages or timing too advanced. The CAT does in fact have to be functioning properly to burn NOX too. I am unfamiliar with what the kit does with either existing EGR if any. high nox can also theoretically occur if the engine is overheating ( although unlikely).

There is no EGR with the Mopar Kit, its eliminated. Timing is permantely set and can't be changed either. I'm taking it back to my mechanic for a final work up will keep ya'll informed. thanx

Just for our info, what was this kit installed on? What was the age & mileage of the engine?

1988 Jeep Wrangler YJ, 150,000 miles on the engine. Compression test was 120 -125 when purchased 4 yrs ago. Not much dofferent now.