CT Mike

My 88 Targa failed CT emissions. The results were:

HC (Limit) 156 - Car scored 39 Pass
CO (Limit) .50 - Car scored .61 FAIL
NOx (Limit) 1094 - Car scored 1083 Pass

Any ideas on what I can do to get the car to pass?
One more year and its over 25 years old and no emmisions! But this year is a different story.
Thanks, Mike

rusnak

How old is the O2 sensor? Last time the engine had a complete tune up? Fresh gas? Should be easy if you start with a good running motor, and check the air/ fuel ratio.

groovzilla

can the '88 motor be detuned for emissions like the 911sc motor by turning the CIS CO adustment down on the sensor plate?? then retuned(dialed back up) after test??

rusnak

Not really. The O2 sensor will take over, and the DME will follow it's program. Changing the parameters (chip, AFM clock spring) are semi permanent, and best left to pros.

theiceman

the nox is right on the limit too. that cat is working overtime
did you put the corre t grade fuel in ? if you put high test in and your car is incapable of burning it tbis will result in higher emmisions also if hour oil is old it will show higher emisions when bur ing.

if you havnt i would do a tune up change the oil and go back for retest

groovzilla

i remember my father in law(a retired boeing engineer)telling me you can get a car to pass by pouring a certain amount of rubbing alchohol into the fuel tank prior to the emissions test - anyone up on this technique? - would it work?

TroyN

Yes, there is a mixture control screw on the air meter AND also a fuel-quality switch on the DME. The FQS is easiest to get to but it's more likely fine tuning the mixture will be what you need. Best adjusted if you have a CO meter either at your mechanic's or something like a Gunson Gastester.

http://www.911chips.com/fuelsys.html

TroyN

Note, re the fqs, you might try position 3, or make sure someone didn't move it from position 0 previously. Again, testing w gas meter is crucial. Good luck!

mfyoung1086

You could accomplish the same thing with additional e85 added to the tank. This trick works fine for water cooled cars where fuel atomization isn't really a problem, but I would think the cooler burning alcohol could in an air cooled motor could create some problems with proper atomization.... but thats just my speculation could work the same if its an hot enough day out anyways and if the mixture is right

I would def suggest an oil change as well if the oil is getting close to it anyways, and it def appears your cat is showing its age

whatever you do please fight the urge to use seafoam or its relatives, unless you really feel like paying for a new cat....

hell dude your so close you should prop just wait for a warm enough day and try again haha

groovzilla

its really ashame some states like california still require emissions on cars older than 25 years - state of washington only requires cars later than 25 years old to pass. and this is a tree hugging, EPA'd to death state.

i can understand these states wanting to cut back on emissions but you have to laugh about it regarding california when you see the tens of thousands of boats/jetskis/lawn mowers and weedwackers w/50:1 mix buzzing away all day. with the bagillion lawyers in calif., some must be frustrated enough that their collector cars won't pass - i'm surprised none put up a good enough challenge to get some sort of exemption.

this year anything older than 1988 is exempt in the state of washington.

mfyoung1086

God you guys are lucky! Has to be pre 72 period in Arizona to be emissions excempt

Lorenfb

"can the '88 motor be detuned for emissions like the 911sc motor by turning the CIS CO adustment down on the sensor plate??"

Actually you can. The 911 3.2 has still basically the same overall system functionally
as the 911SC, i.e. a fuel delivery system with an O2 sensor. In either case the
O2 sensor has a limitation on how much it can correct the mixture. If the AFR
is adjusted beyond the O2 range, the AFR can be changed.

Obviously, the O2 sensor could be left to look like it was still connected and then
the mixture leaned (by adjusting the internals of the AFM - for a 3.2). If the
O2 were left connected then a greater AFR (mixture) change would be required
to force the desired emission level.