emissions 84' 944 A/T

[Jet wrench]

I have an 84 944. I failed an emissions test and I am at my wits end. I replaced the Cat, plugs, O2 sensor, wires, distributer, rotor and air filter. I am .14 above the limit of 2.00. I don't think I have any vacuum leaks and I topped off with 92 octane. I never had problems before and was wondering if there is a throttle positioning sensor and an egr valve on this. The Haynes manual doesn't show them being installed.

[SoCal Driver]

No egr valve. Throttle switch just shuts off the fuel on till the engine is below 1200-1300 rpm.

Check the limits from the last time you had to do smog. Bet they have been lowered.

Also what is .14 and 2.00??? NOx? CO? CO2? HC? What are the other readings?

You might want to visit www.frwilk.com and read about retracking the AFS (air flow sensor).

[mlue]

Originally posted by Jet wrench
I have an 84 944. I failed an emissions test and I am at my wits end. I replaced the Cat, plugs, O2 sensor, wires, distributer, rotor and air filter. I am .14 above the limit of 2.00. I don't think I have any vacuum leaks and I topped off with 92 octane. I never had problems before and was wondering if there is a throttle positioning sensor and an egr valve on this. The Haynes manual doesn't show them being installed.

So close but yet so far!!! Sounds like you have covered the basic that usually causes failed emmissions.

Try checking:

1) All the vacumn hoses. I once had a disconnected hose going to a big black thing (technical term) in the battery compartment area.

2) If your adjustment screw on your AFM was messed with then this will cause you to fail, symtom: the rubber plug is missing from the AFM. Using an allen key turn the adjustment screw clock wise until it stops (remember to keep track of the # of turns as reference). Unscrew (counter-clockwise) the adjustment screw and set it to 7.5 to 8 turns from the bottom and take it for the test.

3) If number (2) does NOT work it could be that the spring for the "barm door" in the AFM is stretched out and needs to be reindexed 1 notch. It could be the wiper arm adjustment like SoCal suggested, if you have to remove the black cover to do this then remember to use O2 sensor safe silicone to reseal it. If you don't want to do this then buy a used AFM or swap with someone.

4) If you are at your absolute wits end, you can run the gas to almost nothing and then put in a mixture of 1 to 2 gallon of 87 octane and 2 quarts of gas line antifreeze (alchol), then take it for the test. Sorry to all the wood fairies out there but Guranted pass!!!

[user426]

I'm in Westchester.....my 84 passed on the second run........It failed on the first run.....my mechanic says the secret to passing is to run the cats till they're red hot.......make sure you hot wire the fans so they are both on.....and take it to the station after a long hot run......good luck

[pokey]

First, run your car nearly out of gas. Then fill up with 87 octane. High octane gas does nothing but burn cooler and slower, and being as your engine is tuned for 87, it will be less efficient and cause more pollution on higher octane. The owners manual has a good description of why, and what gas to run. It says, in the US 87 octane is the same as Europe's 91 octane, because there are different standards of measure, that is why your gas door has a sticker that reads "91 RON" that is the european furmula.

[SoCal Driver]

The adjustment on the AFS is for idle only. Once the barn door opens the bypass is moot.

Still would like to see all your numbers properly referenced.

[Jet wrench]

I failed on the nOX. My reading was 2.14 and the limit is 2.00.

[Eldorado]

gotta love living in Ontario - no emissions tests on cars older than 20 years old!

granted, those are probably the cars that NEED testing... :S

[mlue]

Originally posted by Eldorado
gotta love living in Ontario - no emissions tests on cars older than 20 years old!

granted, those are probably the cars that NEED testing... :S

Ya I hope they stay the course as this spring was my last unless they get wise.

[mlue]

Originally posted by Jet wrench
I failed on the nOX. My reading was 2.14 and the limit is 2.00.

High NOX, the car is running lean or you have very high combustion temperatures.

Try what user426 posted that may help you get the pass. Clean injectors are always a good thing too.

[mlue]

Originally posted by SoCal Driver
The adjustment on the AFS is for idle only. Once the barn door opens the bypass is moot.

The some smog test like where I live samples both at idle and at 2500 rpm.

[todwic]

I have the same car. I have faced and am facing the same prob you do. Bad for two reasons

failing smog sucks. No tab=more expense, not legal, routine traffic stop auto target, DUI check points=ticket or tow

Now yer tagged as a gross poluter (at least in CA)=Smog test EVERY year. Gen. drag

Solution: Find a P-car dealer that does smog and has the impression that you'll be a loyal cust. Mine was $80. Best money I've spent on her yet.

[todwic]

Or you can have the check done when yer almost on empty, throw in a bottle of rubbing alcohol in the tank. Worked on my turbo, the N/A is next. (per Auntie Wilk)

[mplight]

I have just aquired an '86 944, failed emissions as well.
the NOx, HC, and CO2 tested well within limits, but the CO is off the charts at sta

[mplight]

I have just aquired an '86 944, failed emissions as well.
the NOx, HC, and CO2 tested well within limits, but the CO is off the charts at start of test, then drops down.
I have been running High Octane...mistake? should i be running 87???
Please help if you can I have a week before registration is suspended!!!
thanks.

[SoCal Driver]

Post the actual test numbers as there is a relationship between them. You may be able to adjust the DME timimg to compensate.

[mplight]

NOx = 1.74 limit = 3.25
HC = 2.10 limit = 2.25
CO = 68.15 limit =23.74

the CO2 787.09 no max limit

thanks!

[bigyagi]

not sure if its any help, but check my new posting, under emissions. i have added my last test results, albeit for ontario, but it shows the various tests they do. i dont think they even checked my cat!!
bob.

[mplight]

Thanks BIG TiME!! Just signed up to Pelican and want to say you folks are great! Really happy with my Guards Red RIDE.
Marc

[mih0001]

Does 87 octane plus alcohol have adverse effects on the engine? I just failed the emissions test today in my 1984 944 with high hydrocarbons and CO. NOx was luckily fine.