dr bob

I think the Sunday wrenching is at 928 International, not at Rob's. Check with him before you drive over to Irvine to confirm the real location. I have a prior commitment and won't be able to join you guys. I don't get any more play days until sometime in late May. Wish I could join you guys.

Bill Ball

I'm with Jim regarding the aftermarket cats. Seen it several times after just a couple of years.

RED SHARK 1990

Calling ROB EDWARDS??????Alright could someone chimed in the last post made by Rob.Is it at his house or at 928intl?

Adam Geist

About two years ago, I failed NJ's emission test with my green '86.5. After replacing the O2 sensor, I passed the emissions test with very clean readings - this was with the factory cat set-up. Shortly after, I installed an x-pipe and high-flow cats.

A couple of weeks ago, I failed NJ's emission test for high NOx. CO and HC were within spec. I drove the car for 30 miles before before heading to the inspection station and then sat for about an hour before the tailpipe sniffer test.

I currently have platinum sparkplugs installed and will swap-out to copper ones before I head back to the inspection station next weekend.

GregBBRD

Wait until you see the new laws in California regarding cats....Now are both car and location specific. No more generic "high flow cats".

Rob Edwards

Luan-

My place in Irvine.

-Rob

ROG100

Luan has high flow aftermarket cats from Dave Lomas. Mine are still good after three years and I pass emmissions very clean.
What concerns me is that the air pump is still connected and pumping air into these cats on Luan's car.
Would that do any damage to the cats as the new cats do not normally have an added air flow.
Roger

RED SHARK 1990

What is going on now still failed...we changed to bosch copper plus plugs and drove like an hour .The test results were-15mph-rpm at 1375-%co2-meas-13.1,%o2-meas-2.4,HC(ppm)-MAX-108,GP-283,MEAS-79,CO(%)-MAX-0.71,GP-2.21,MEAS-0.04,NO(ppm)-MAX-767,GP-1957,MEAS-1770=FAIL.NOW at 25MPH-RPM at 1395,%CO2-MEAS-12.9,%O2-MEAS-2.7,HC(ppm)-MAX-83,GP-233,MEAS-71,CO(%),MAX-0.58,GP-2.08,MEAS-0.02,NO(ppm),MAX-706,GP-1757,MEAS-1852=GP. I FAILED EVEN WITH A BOTTLE OF CRC EMISSION GUAR TO PASS OR MONEY BACK IN DOUBLE.PLEASE CHIME IN......i also noticed several weeks ago rpm idle slightly above 500rpm low idle? mass sensor rebuilt a year ago,fresh intake and hoses included injector seal kit,o2 sensor about 40,000 miles,could the LH GOING?X-PIPE HI FLOW DAVE LOMAS?RUNNING LEAN COND WHAT CAUSES?

Hilton

Still running way lean, usually a symptom of a failing or old MAF, although you say you have a rebuilt one so thats a relatively low chance (but not impossible - I know someone with an '87 S4 who went through pain diagnosing everything else before getting the rebuilt MAF replaced).

The low idle is weird - not seen that before except when I had a coil plug loose and was only running on 4 cylinders.

Richard S

Check my old thread, I had a similar experience. https://rennlist.com/forums/928-foru...l-warming.html

In my case, I fixed the frayed wires on the mas sensor connector, and installed some stock cats.

If I were you, I would remove the x-pipe and hi-flow cats and put the stock cats back on there for the test. Also check your connector wires just for the hell of it.

Good luck.

Rich

RED SHARK 1990

CA smog test please chime in how may tries do i have till i do?chime in please....1 week till shoot the cow..

dprantl

- Disconnect the battery ground strap for 5 minutes
- Put in a known good MAF and check its connections
- Put in a known good O2 sensor and check its connections
- Check for vacuum leaks
- Put in known good stock cats

If you don't pass after this, your LH brain is having problems or you missed a wiring issue or vacuum leak.

Dan
'91 928GT S/C 475hp/460lb.ft

douvillier

As one who is in the midst of studying for the ASE L1 test I read your plight with interest. Based on your numbers your big problem is the high NOx. When a problem comes into a repair shop the first questions you ask is "What have you done?". With the modified exhaust and high flow cats I would suspect that is your problem. I would suggest going back to bone stock and letting it alone. The air pump and stock cat is designed to work together to lower the NOx. Just make sure your Air Pump is working properly, as that is the primary device to lower NOx. Of course now your car has been identified by the State as a Gross Polluter with all the fun that entails.

Bill51sdr

Dang Luan, your post(s) gave me a headache I hope you kept your factory cats. Aftermarket hi-flow cats are notorious for this kind of failure. As has been said above, replace them.

RED SHARK 1990

Alright only less than a week to have my car smog legal,so i panick and made an appointment to have a pair of magnaflow CA cert catalytic converter-model 36304 to be replaced the Dave Lomas cats.Also borrow a rebilt MAF,new o2 sensor and i will check the vacuum lines...If the test failed the red head will have to stay home.