cat bypass for obdII Anyone tried it yet?
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Yeah Boris, the more I think about it, the less enthused I become. I think I will stick to an upgraded chip and wait for the bugs to get worked on the supercharger
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Originally posted by Boris Teksler
Alex,
one other thought... you may want to see someone's car that has cat bypass pipes. the smell is potent!!! i put a set on my 964 once and took them off within 2 weeks. Everytime i pulled into garage, stopped at a light with the top down ... - it was just simply nasty!
cheers,
boris
Alex,
one other thought... you may want to see someone's car that has cat bypass pipes. the smell is potent!!! i put a set on my 964 once and took them off within 2 weeks. Everytime i pulled into garage, stopped at a light with the top down ... - it was just simply nasty!
cheers,
boris
It actually reminds me of the good ole day's cars.. old muscle cars and my 1st car (a 73 super beetle)... you know, that leaded gasoline without any cats...
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
...I sort of like the smell and that reminder.. but then again, I know it is really bad for you to stand there and inhale the stuff.. LOL
![hiha](https://rennlist.com/forums/graemlins/roflmao.gif)
![hiha](https://rennlist.com/forums/graemlins/roflmao.gif)
#18
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An R/R of the battery won't reset the DME and as a such won't affect the
OBDII readiness. The later DME's use non-volatile memories (EEPROM/Flash)
versus standard RAMs to store the readiness states, not like the early
993/964 DMEs which could be reset/erased by removal of the battery.
OBDII readiness. The later DME's use non-volatile memories (EEPROM/Flash)
versus standard RAMs to store the readiness states, not like the early
993/964 DMEs which could be reset/erased by removal of the battery.
Last edited by Lorenfb; 03-30-2004 at 01:16 AM.
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The early 993s ('94/'95) use a 55 pin DME unit which didn't have the OBDII features.
Therefore, these cars should not be required to comply with OBDII requirements
even though these cars use the standard OBDII interface connector.
It's only '96 and later cars which must comply with OBDII. The '96 and later
993s have OBDII 88 pin DMEs. This DME unit also provides the immobilizer
capability. I've seen some early '96 993s which fail OBDII because Porsche
had an OBDII interface problem (DME firmware).
Therefore, these cars should not be required to comply with OBDII requirements
even though these cars use the standard OBDII interface connector.
It's only '96 and later cars which must comply with OBDII. The '96 and later
993s have OBDII 88 pin DMEs. This DME unit also provides the immobilizer
capability. I've seen some early '96 993s which fail OBDII because Porsche
had an OBDII interface problem (DME firmware).
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Wow, Jeremy! What a nice timing! Thanks for digging this thread out and bringing it back to the top.
I am right in the process of trying to pass NC state inspection and have like four checks returning "NOT READY" diagnosis(including "secondary air"). And that is after more than 500 mile drive since top-engine rebuild. Well, 400 miles I drove in 6 gear - that was from Atlanta to Raleigh.
Guys in local shop[generic, but suggested by DMV in regards to inspection] were really puzzled - they have latest OBDII software and don't see "NOT READY" coming up after 500 miles of driving at all. They suggested to talk to Porsche dealer. Dealer(Leith Porsche in Cary) said "drive for at least 25 minues with RPM not dropping below 2500, that is the first thing we would do before trying anything else". Peter from the shop who did top-end rebuid is faxing detailed instructions on what are the steps neccessary to make engine "ready" for OBDII check.
I also was surprised to learn that in our county in our state during state inspection they DON'T do separate standalone emission test on cars produced after 95, only on pre-95. On new cars(96-) they just read OBDII computer status. Immediate thought was "why did I bother with 'secondary air' error code then, while I could buy OBDII tester and reset it"(putting aside the fact that 'secondary air' clogged usually means valve guide wear). But I'm not sure that would work(as Loren suggests), because if I understand correctly, once you reset the code, it will come up as "NOT READY", not as "PASS" in OBDII state inspection test - i.e. test will not pass.
I am right in the process of trying to pass NC state inspection and have like four checks returning "NOT READY" diagnosis(including "secondary air"). And that is after more than 500 mile drive since top-engine rebuild. Well, 400 miles I drove in 6 gear - that was from Atlanta to Raleigh.
Guys in local shop[generic, but suggested by DMV in regards to inspection] were really puzzled - they have latest OBDII software and don't see "NOT READY" coming up after 500 miles of driving at all. They suggested to talk to Porsche dealer. Dealer(Leith Porsche in Cary) said "drive for at least 25 minues with RPM not dropping below 2500, that is the first thing we would do before trying anything else". Peter from the shop who did top-end rebuid is faxing detailed instructions on what are the steps neccessary to make engine "ready" for OBDII check.
I also was surprised to learn that in our county in our state during state inspection they DON'T do separate standalone emission test on cars produced after 95, only on pre-95. On new cars(96-) they just read OBDII computer status. Immediate thought was "why did I bother with 'secondary air' error code then, while I could buy OBDII tester and reset it"(putting aside the fact that 'secondary air' clogged usually means valve guide wear). But I'm not sure that would work(as Loren suggests), because if I understand correctly, once you reset the code, it will come up as "NOT READY", not as "PASS" in OBDII state inspection test - i.e. test will not pass.
#24
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Some of the subaru guys have figured out a few ways around the CEL on OBDII cars, which may apply to P-cars as well.
1) resistor inline between the sensor and the ECU ($20 from Pony Express, or $0.15 from Radio Shack)
2) a "mini cat" in the O2 bung of the downpipe (godspeed makes one for Subarus)
3) a O2 sensor relocator elbow (see link below)
4) smarter version of 1) (scoobysport makes one)
http://forums.nasioc.com/forums/show...l&pagenumber=1
I think the o2 sensor relocator elbow may work on the P-cars; it basically takes the sensor out of the main exhaust stream, but feed it enough exhaust gases to make it think the cat is still installed.
1) resistor inline between the sensor and the ECU ($20 from Pony Express, or $0.15 from Radio Shack)
2) a "mini cat" in the O2 bung of the downpipe (godspeed makes one for Subarus)
3) a O2 sensor relocator elbow (see link below)
4) smarter version of 1) (scoobysport makes one)
http://forums.nasioc.com/forums/show...l&pagenumber=1
I think the o2 sensor relocator elbow may work on the P-cars; it basically takes the sensor out of the main exhaust stream, but feed it enough exhaust gases to make it think the cat is still installed.
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Hey Loren thank you for the info, and I didn't even have to call and bug you like I usually do. I think that by going to the referee station we can get this car to pass without too much trouble. At least in CA they are aware that these cars have trouble interfacing with the state computors.
Max - thank you for the link buddy!!
Max - thank you for the link buddy!!
#26
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FWIW Alexander, I have found that driving the car between 50 and 60 MPH, below 3000 RPM for about 2 min. then slowing down or speeding up which breaks the cycle and repeating this process 4 times will reset at least 4 monitors in one shot, again usually not the secondary air which is not activated during these drive cycles.