Q won't pass smog

[activesuspensionnomo]

Hello Q45oligists: I have a 1991 Q45 with 211K miles that has failed the Hydrocarbon part of the smogtest. At 15 mph HC measured @ 95 max is 71, at 25 mph HC measured @ 55 max is 54. I put in fresh mobile 1 and cleaned KN airfilter prior to test. I'm currently jobless and don't have very much funds. Thank you all for your suggestions. Nomo

[Infinitiguy19]

Return the worse than useless K&N filter and get a OEM filter.

GENTLY clean the MAF with electrical parts cleaner or replace if too late.

[Q45tech]

First thought is replace O2 sensors [after testing efficiency by expert], but 19 year old cats may just be worn out and need of replacement caused by previous abuse.

Unfortunately a vehicle could care less about the employment status of owner.
Failure to maintain and repair is a mechanical crime that keeps on giving.

[MinisterofDOOM]

Looks like you might be running a little rich, but you're not really far from passing. I'd second Paul Wall's recommendation to go back to the stock airbox and filter. That alone might correct the problem.

You might also try adding some Techron or a pass-emissions formula to a full tank before testing. Due to the ingredients they use, they can reduce hydrocarbon emissions. Most pass-emissions formulas are really just concentrated injector cleaners.

[Q45tech]

Not sure how the car has been driven previously? Are you agressive enough in blowing the soot out? City and grandpa driving can clogg up a HP engine.

Has it been driven 70 mph with WOT blips to 80 mph repeatedly for 15 minutes then tested?


Gotta get those old O2 and cats HOT to clean them up some.

If traffic/police make 80 mph blips difficult then drive in 3rd gear or 2nd or 1st - remember the engine is safe to 90 mph in 2nd.

[Lokim]

Hop on the freeway and drive for 20 min in light traffic out somewhere and back. Get off the freeway and go straight to the testing station. Don't stop for gas, don't stop for lunch, just keep the car hot and running. Emission testing's worst enemy is lack of heat in the catalytic converters.

Paul: I resent the remark about the K&N air filter. I have one in mine and passed emissions with less than 50% of any allowable limits. Plus, the throttle response got much snappier after installation! Their oil filters suck, though. They have the same or less filter media surface area than filters that are half the price...

[Infinitiguy19]

Paul: I resent the remark about the K&N air filter. I have one in mine and passed emissions with less than 50% of any allowable limits. Plus, the throttle response got much snappier after installation! Their oil filters suck, though. They have the same or less filter media surface area than filters that are half the price...

I am just stating a fact. I am saying that I nor any other knowledgeable NICO members will put a K&N filter in a Q. And plus after all its your car you can follow what facts show or you can do what you want. Just take a gander at what it says in my signature about smart people.

[Lokim]

Paul: I resent the remark about the K&N air filter. I have one in mine and passed emissions with less than 50% of any allowable limits. Plus, the throttle response got much snappier after installation! Their oil filters suck, though. They have the same or less filter media surface area than filters that are half the price...

I am just stating a fact. I am saying that I nor any other knowledgeable NICO members will put a K&N filter in a Q. And plus after all its your car you can follow what facts show or you can do what you want. Just take a gander at what it says in my signature about smart people.

Ok Paul, I'll bite. What exactly makes the K&N air filter "...less than useless...?"

[Infinitiguy19]

http://www.bobistheoilguy.com/cms/index ... &Itemid=76

http://docs.google.com/fileview?id=0B5V ... ZDEx&hl=en

Air Filter Replacement

When you install a fresh K&N in Q [we don't recommend it] the oil from the filter will coat the thermistor and heated element in the
MAF causing massive errors in ECU. The Q MAF does not have a heated cleaning cycle like some GM and others to burn off the
contamination. Be very careful in using spray brake cleaner to clean the 2 indise elements ......or you get to buy a new MAF. The
K&N [cone] does nothing but make a loud sound and cause severe errors in Summer another case of developing a false test [not real
world conditions] to satisfy marketing of a product!

Q45Tech-http://docs.google.com/fileview?id=0B5V ... MGFh&hl=en

I can't seem to find another post where Q45Tech admitted to using a K&N filter an said himself it was a mistake, But its there.

[Lokim]

Ok, Paul, I see how the oil contamination is a problem. I went out and grabbed a Napa Gold air filter and installed it while doing my oil change today. I also cleaned the MAF w/ CRC's MAF Sensor Cleaner.

Anybody wanna buy a K&N for their Q45? Only has 300 miles on it...

[Infinitiguy19]

I am glad I could actually change your mind about K&N mind.