Now to pass emissions test - help?
01-28-2004, 10:47 AM
#1
Addict
Rennlist Member
Rennlist Member
Thread Starter
Join Date: Jul 2002
Location: Atlanta
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
Now to pass emissions test - help?
Hi all,
Well, I'm very happy to have joined the Turbo owners' club. Last weekend I picked up a '91. It's in beautiful shape. It's got headers and a 1-bar spring. I understand that the car is running rich to compensate for the spring. I thought I'd give it a shot passing emissions testing, and not surprisingly, it failed - mostly for running too rich (according to the guy from the inspection shop).
I spoke to the mechanic who serviced the car for the PO and he said "just have a mechanic lean it out and it'll pass, then take it back and have him put it back." Well, that's nice, but I'd like to do it myself. Of course, I have no idea how. Is this an easy process? (I can turn a wrench OK.)
Also, the mechanic said that he's had these cars pass w/o cats. True?
Thanks in advance,
Well, I'm very happy to have joined the Turbo owners' club. Last weekend I picked up a '91. It's in beautiful shape. It's got headers and a 1-bar spring. I understand that the car is running rich to compensate for the spring. I thought I'd give it a shot passing emissions testing, and not surprisingly, it failed - mostly for running too rich (according to the guy from the inspection shop).
I spoke to the mechanic who serviced the car for the PO and he said "just have a mechanic lean it out and it'll pass, then take it back and have him put it back." Well, that's nice, but I'd like to do it myself. Of course, I have no idea how. Is this an easy process? (I can turn a wrench OK.)
Also, the mechanic said that he's had these cars pass w/o cats. True?
Thanks in advance,
01-28-2004, 02:54 PM
#3
Rennlist Member
Congratulations and welcome,
You can make these adjustments yourself but I don't recommend it. You will need a 3 mm allen wrench and some knowledge of your CIS/K jetronic injection system. There is a small hole on the top of the fuel distributer that you insert the allen wrench into. You have to be careful not to damage the air flow plate in the process. I don't remember which direction to turn the wrench (I think it is clockwise) but it will make the adjustment you need. I will attempt to look this up for you. I believe if you look at some of the previous threads someone had posted the direction.
One problem, you need a way of metering the levels to determine if you have made the adequate adjustment. Doesn't your mechanic have access to a place to have the car inspected so they can do this for you?
How about some pics of the new toy.
LOL
You can make these adjustments yourself but I don't recommend it. You will need a 3 mm allen wrench and some knowledge of your CIS/K jetronic injection system. There is a small hole on the top of the fuel distributer that you insert the allen wrench into. You have to be careful not to damage the air flow plate in the process. I don't remember which direction to turn the wrench (I think it is clockwise) but it will make the adjustment you need. I will attempt to look this up for you. I believe if you look at some of the previous threads someone had posted the direction.
One problem, you need a way of metering the levels to determine if you have made the adequate adjustment. Doesn't your mechanic have access to a place to have the car inspected so they can do this for you?
How about some pics of the new toy.
LOL
01-28-2004, 03:25 PM
#4
Addict
Rennlist Member
Rennlist Member
Thread Starter
Join Date: Jul 2002
Location: Atlanta
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
Pics after I wash the car this weekend for sure.
Thanks for the input. It sounds as if I may want to have a shop do it. I don't have a Porsche mechanic here yet, as any work I've had to do I've been able to do myself, but I have some recommendations so I think I'll make a few calls.
Thanks for the input. It sounds as if I may want to have a shop do it. I don't have a Porsche mechanic here yet, as any work I've had to do I've been able to do myself, but I have some recommendations so I think I'll make a few calls.
01-28-2004, 05:25 PM
#5
Burning Brakes
Join Date: Jun 2001
Location: Stockholm, Sweden
Posts: 1,232
Likes: 0
Received 0 Likes
on
0 Posts
Hey, look at this link, all the info you need.
http://www.bentleypublishers.com/gal...=pc94&seqnum=9
Right=Rich
Left=Lean
http://www.bentleypublishers.com/gal...=pc94&seqnum=9
Right=Rich
Left=Lean
01-28-2004, 05:41 PM
#6
Burning Brakes
Join Date: Jun 2001
Location: Stockholm, Sweden
Posts: 1,232
Likes: 0
Received 0 Likes
on
0 Posts
Also, be careful when you turn this thing, make tiny adjustments.
I turned it like 1/4 of a turn and CO changed with more than 2%.
But best thing is to have someone with a CO tester do this for you.
Takes 5 minutes to do.
Or you can get a CO tester for yourself.
Brent on www.911turbo.com forum is selling his CO tester for $100 USD.
Good luck with your new car!
I turned it like 1/4 of a turn and CO changed with more than 2%.
But best thing is to have someone with a CO tester do this for you.
Takes 5 minutes to do.
Or you can get a CO tester for yourself.
Brent on www.911turbo.com forum is selling his CO tester for $100 USD.
Good luck with your new car!
Trending Topics
01-29-2004, 01:48 PM
#8
Addict
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Dear John,
The same question has come up on the 964 forum. I am not quite sure if you have a cat installed or not. However regardless you have to get everything hot for the emissions test. If the test is done with a cold engine, cold exhaust and cold O2 sensor you will never pass. Hot hot hot to get the Turbo running in controlled lean or closed loop operation.
Ciao,
Adrian
964C4
The same question has come up on the 964 forum. I am not quite sure if you have a cat installed or not. However regardless you have to get everything hot for the emissions test. If the test is done with a cold engine, cold exhaust and cold O2 sensor you will never pass. Hot hot hot to get the Turbo running in controlled lean or closed loop operation.
Ciao,
Adrian
964C4
01-29-2004, 02:41 PM
#10
Pro
Join Date: Dec 2001
Location: sacramento
Posts: 542
Likes: 0
Received 0 Likes
on
0 Posts
Ya, what Adrain said!
Hot car on a cool day w new plugs and a new O2.
The o2 takes over the mix at idle and on cruse if the O2 is hooked up and the Co setting is reasionabley close.
Some disconect the O2 so it takes the corections out of the loope and runs like and earlyer one. Check to see if yours is pluged in.
After you pass smog I'd try to reset co to 3% with the O2 disconected and hook the o2 back up so it runs clean but when you floor it it defalts to the richer setting when the throtle position goes past somthing like 7 or 15%.
Better gas milage and less carbon build up potental.
It least that is my thought and $.02's worth. (And not worth a penny more.)
Keith
Hot car on a cool day w new plugs and a new O2.
The o2 takes over the mix at idle and on cruse if the O2 is hooked up and the Co setting is reasionabley close.
Some disconect the O2 so it takes the corections out of the loope and runs like and earlyer one. Check to see if yours is pluged in.
After you pass smog I'd try to reset co to 3% with the O2 disconected and hook the o2 back up so it runs clean but when you floor it it defalts to the richer setting when the throtle position goes past somthing like 7 or 15%.
Better gas milage and less carbon build up potental.
It least that is my thought and $.02's worth. (And not worth a penny more.)
Keith
01-29-2004, 05:32 PM
#11
Addict
Rennlist Member
Rennlist Member
Thread Starter
Join Date: Jul 2002
Location: Atlanta
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
Very interesting. I'll give that a shot. I did try to warm the car up good before bringing it in, but the richness did me in. In fact, the CO test read 3.02%, but I have no idea about the O2 sensor.
01-30-2004, 05:15 AM
#12
Addict
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Lead Rennlist
Technical Advisor
Rennlist
Lifetime Member
Dear John,
Maybe your O2 sensor control unit is not switching to closed loop operation.
This can be caused by a failed O2 sensor or simply because the O2 sensor did not reach the minimum operating temp of 600F. It might also be worth checking the voltage supply to the O2 internal heater.
Personally I think you were not hot enough. Warm is not good enough, hot hot, hot.
Ciao,
Adrian
964C4
Maybe your O2 sensor control unit is not switching to closed loop operation.
This can be caused by a failed O2 sensor or simply because the O2 sensor did not reach the minimum operating temp of 600F. It might also be worth checking the voltage supply to the O2 internal heater.
Personally I think you were not hot enough. Warm is not good enough, hot hot, hot.
Ciao,
Adrian
964C4
