Failed California Smog :(

[misterCAFE]

87 325is 230k
havent been driving the car much lately, but drove for about 20-30 min. including freeway/high rpm to heat the cat before the test. Still failed horribly.
Failed both 15 & 25mph tests For HC & NOx.

HC: 15mph max:114 Measured:206
25mph max:89 Measured:130

NOx: 15mph max: 785 Measured:2342
25mph max: 724 Measured:1764

New Cat or are these results indicating something else?

[Sean S.]

Wow, there are a lot of CA smogs failing due to NOx lately. I think the state tightened the screws again. .... Anyways, high HC can usually be cured by Seafoam and a good drive, NOx is indicative of high combustion temps caused by a lean burn and an ambient air leak so check the usual suspects such as: intake boot, intake gaskets, split air hoses, etc. Consider that your o2 sensor may need to be replaced as well.

I just went rounds with my old 95 Jeep Wrangler which passed smog for 15 years here in CA but failed this time on NOx . Ended up being a split vacuum hose and an O2 sensor, but it was super frustrating as it had never failed before. Makes me wonder what I'm going to be up against next time I have to smog my vert or E34.

[varg]

It's most likely either an ailing cat or a lean condition resulting in a random lean miss. First I would check for unmetered air entering the system (vacuum and post AFM intake leaks), then if the cat and O2 sensor are old, I would replace them.

[misterCAFE]

Ok status on e30: still not smogged :(

Car sat after failing smog for another few months. Began driving it again alot recently, plus I seafoamed her and gave her some fresh oil. Went to get another test because free retest so what the hell. Got the car super hot before and almost same results.

So I went ahead and ordered a new weld in cat.

Will report back when its welded in and I take the test

[Crazyhorse13]

disregard