Mother

Interesting reading, I have told FVD to hold on the tune temporaily, I found some leakage issues. A torn aftercooler reducer (has been ordered along with T-Clamps) and the intake has to be refabbed which is almost completed. I will get new readings when running again shortly after parts arrive.

Tippy

I used a sewer pipe reducer from Home Depot for the inlet side of the S/C. A few dollars and it worked for years. It connected the daddy sized K&N cone (which I dont recommend) filter to the inlet of the S/C.

T-bolt clamps are must, I was popping off the worm gear clamps under high boost on the discharge tube side.

Mother

Well the car runs 100% better and does idle, no hunting or smoke with new intake and the $1.00 resistor, but still seems alittle rough with no misfires indicated. I cannot remember, but I think I had a error message with one of the O2's and will re check later just wanted to tell eveyone that helped thank you and GOOD JOB! The new info was sent to FVD and we will see what they think. 1999 not sure which O2 voltages after cats since there only seemed to be the one for right and left banks (Conv) but seemed one bank running very lean hope this is what you where talking about, if I missed something let me know I can get more data. Attached in 2 parts are the new numbers that will lend some indication of what the engine is doing plus new crappy video and Excel spead sheet at:

http://www.webbspot.com/Porsche/fvdvideo.html

I also had 2 error/fault codes:

1. P0134 code 10 - O2 sensor ahead of Cat conv.
2. PO1115 code 13 -Heating power O2 s ahead of cat bank 1

I think I need to check my O2 sensor connection.

1999Porsche911

What size resister did you use?

Mother

1999, A 560K resistor was used inline with wht/blue wire. Do the MAF Volt readings seem closer to what they should be at idle? Still not sure of A/F at this point. On reading "Sensor-signal period ah. of cat. c. bank 1" (not on graph) reads 0.00 resistance which I will clean connector today and see error stays cleared.

1999Porsche911

Your after cat O2 sensors are reading too high (very rich) on both banks at idle. You need to get your MAF reading down closer to 1. Your tuning will get you there. Take it out for a spin and while watching the after cat O2 sensors, see what they read at WOT. If they read 88 volts or higher, you are more than safe as far as F/A ratio goes.

Mother

Still have concerns, I cleaned connectors on bank 1 (before/after) cats and you can see my values have now changed? To me looks like a lean conditon? The before data above showed a rich conditon, "after cat" now it is lean and before still reads about the same as before? Did I just loose 2 O2's ?

F5/F7 bank 1 - F9/F10 Bank 2

1999Porsche911

Assuming you data is accurate, you have a problem. He or some possabilities:

Assuming Bank 1 readings are accurate:

Leaking injector(s) bank 2

Assuming Bank 2 readings are accurate:

- Exhaust leak on bank 1 before sensors
- Vacuum leak effecting bank 1 only
- clogged injector(s) on bank 1

OR

Every reading of your before cat sensor (bank 2) show RICH, which means it is not functioning???? If it is not fluctuating high to low every second or so, the sensor it not working. If the computer sees that the sensor is at the voltage you show, it should be cutting off fuel to that bank. However, your bank 1 sensor is also consistantly low. You need to verify that the before cats sensors are going from high to low by watching them while idling. MAKE SURE your engine is warmed up and in CLOSED LOOP. They do not function to control fueling in open loop.

Mother

What do you mean open/closed loop? I'll add fuel to the fire here Are the O2 resistance values in data of the actual O2 sensors? If so, I would think these values should change constantly if the sensors are working and one in bank 1 is reading Zero? I think that bank 2 readings are correct because of fault code 1115 not clearing which is a bank 1 problem "O2 heater". All values you have seen are of car warmed up.

Mother

I just can not get past the Fault Code 1115, so I ordered a new O2 sensor for piece of mind. Let you know my findings. I think both banks should read about the same weather the left one is lean or right bank is rich. My intake (Distributor) has all new O-Rings and new exhaust gaskets where added for my exhaust so I am ruling that out also for now. I can also move the new O2 from one side to the other to see which one is not reporting correctly. 1999 is assume by closed loop that the computer is running off real sensor paratmeters and not computer set points when cold?

1999Porsche911

Yes. In closed loop, the before cat sensors should be oscillating high to low. If not, sensor is bad.

Mother

Ok, an update the new (bank 1 O2 before cat) sensor has be installed and car runs better and Error Code 1115 I had previously has cleared. It seems rich at idle but leaner once warm and the numbers (O2 V) seem better, but lean after cats? Note: On image first votages are of bank 1. Feeling more I confindent drove it down street at idle but have a "CLICKING" noise that seems to be comming from wheels on both sides, I had redone the brakes with new pads so I still am not ready for Dyno I made a video of the sound tell me what you think:

http://www.webbspot.com/Porsche/video/clicking.3gp

Or go hear also for both spread sheet and video.

http://www.webbspot.com/Porsche/fvdvideo.html

1999Porsche911

First of all, you can tell absolutely nothing from a snapshot of the primary O2 sensors at idle. Secondly, you are not running lean if the secondary sensor numbers are to be believed. Thirdly, you still need to lower your MAF voltage Doubleup the size of the resister.

Then take a look at the after cat sensor readings at WOT at maybe 5000 rpm.

Mother

What voltage SHOULD I have at idle for the MAF that would also produce the proper voltage at WOT? The reason for installing the new O2 was because of the error 1115 showing up as lean condition on earlier graph on this page. The rear "clicking Noise" is prohibiting me from WOT runs as noted in the video at above link.

1999Porsche911

Take a look at what the flow is of the MAF. You need to keep it below .95 lbs/min at an idle of 800. Slightly higher for higher idle and lower for lower idle. Probably closer to a 1.30 voltage from the MAF. I have no idea what your spreadsheet is showing as the voltage is all over the place.