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Oh heck, I've said it privately and I'll now say it publicly, JFP has done more IMS swaps than any of you combined. He has to pay in reputation and/or dollars if any of his work fails. He has a vested interest in doing it right the first time. He has no financial connection to LN. He chooses parts for their reliability and their ability to not cost him time, money and reputation. Because if it fails, it costs him in all three areas. How do I know all this? Well I've been following this issue for at least 12 years to back before any Flat6/LN product was publicly available. I know how many engines they blew up testing. And since LN was the first vendor to produce a kit and the first to produce instructions and tools for something Porsche said couldn't be done, I got interested and was talking back in the day pretty regularly to Jake, emailing to Jake and Charles. How many bearing materials did they use? How many versions of the races? You buy today you aren't getting their first version of either the bearing, the accessories, the instructions or the tools. You'd be buying well beyond the 10 thousandth one they sold. It is your car, your money, your choice. He will probably delete this but if it saves someone from going off in a wrong direction...
If you are talking a small piece of body work at the top of the rear fender just behind the doors, in early Boxster models they were for attachment of a roof/hood luggage/ski/bike rack. Underneath them are mounting bolt holes I presume. IIRC you just pry them up and off. I remember when I crashed my '99 one of them popped off due to the door being driven back into it. By '01 they were not fitting them.
Since the LN bearings are made uniquely for them with unique races and other parts of the kit also unique ... and since the instructions have gone through many revisions to improve them and since the LN tools are designed to make the process successful .... Not ever saying that other approaches can't be successful.
And battery polarity was correct?
I've seen very few if any transmission experts posting on all the forums I frequent. Partially because few OBD2 transmission diagnostics are available cheaply. But mostly because people with the TIP just take it to a ZF specialist as they may be less inclined to DIY.
Any history you have would help too. Miles on car. When did the problem start. Anything happen around the same time. That way when you bought it? The fact that it is on a single side of the engine helps rule a few things as less suspect. Use the Durametric to look at cam deviations.
Always a good idea to either: 1. include your model year and model in your profile so it shows next to your message. 2.Or include the info in your posting. Either helps people trying to help you. - Short circuit in wiring harness – Sluggish throttle Note The vehicle is in emergency air function mode, i.e. the engine is turning at approx. 1200 rpm
Credit to Brett The O2 sensors do just that, sense the amount of O2 in the exhaust gas relative to the amount of O2 in ambient air. Perfect combustion of a perfect mixture of air and fuel (around 14.7/1 air/fuel ratio) leaves behind only CO2 and water as products of combustion. All the oxygen gets consumed in the combustion and combines with all the carbons and hydrogens. If there is not enough fuel (lean mixture), then all the fuel gets burned leaving some oxygen left over. Conversely, if there is too much fuel (rich mixture), then all the oxygen gets burned leaving behind extra hydrocarbons (fuel). Now an oxygen sensor outputs a voltage between 0 and about 1 V depending on the difference between the amount of oxygen in the exhaust and the amount of oxygen in normal air. If there is a lot of oxygen in the exhaust (lean mixture condition), the sensor outputs close to 0 volts. Conversely, if there is no oxygen in the mixture (rich condition), then the output is close to 1 V. These O2 sensor voltages are read by the computer. This is the feedback loop that tells the computer how the engine is performing with regard to air/fuel mixture. It's impossible for the computer to hold the exact perfect air/fuel mixture constantly, so the way mixture control is designed is for the computer to continually adjust the mixture from very slightly rich to very slightly lean and back again using feedback from the pre-cat O2 sensors. This means that the pre-cat O2 sensor signal will oscillate back and forth from high to low to high to low voltage as the computer adjusts the mixture. In a normal running engine at idle the signal goes from low to high voltage and vice versa about every 1 second, with a transit time from low to high (or vice versa) being about 200-300 milliseconds. This transit time is important because as an O2 sensor ages, the transit time gets longer, and eventually it can get too long such that the computer will call it a malfunction and signal a check engine light and fault code for a slow responding O2 sensor. O2 sensors need to respond to mixture changes quickly so that the computer can keep up with the proper mixture adjustments. So the bottom line is that the pre-cat O2 sensors should oscillate between about 0.2 to 0.8 volts regularly (about every 1 second at idle) in a healthy engine. The post-cat O2 sensors are identical to the pre-cat O2 sensors (same voltage outputs). They are there only to monitor the performance of the catalytic converters. So, as discussed, the pre-cat sensor signals are oscillating between 0.2-0.8 volts. Once the exhaust gasses pass through the catalytic converter, most (all, in theory) excess fuel (hydrocarbons) will be combusted thus reducing hydrocarbon emissions. The cat uses oxygen in the exhaust to combust the fuel. So what you end up with in the exhaust after passing through the cat is a gas mixture that is reduced in hydrocarbons and reduced in oxygen relative to the mixture entering the cat. The post-cat exhaust gas mixture should be CONSTANTLY low in oxygen if the cat is doing its job of burning excess fuel. Therefore, the post-cat O2 sensor signal should be a constant lower voltage reading (not oscillating). So, if the post-cat O2 sensor is seen to oscillate just like the pre-cat O2 sensor, that means that the post-cat sensor is seeing the same gas mixture as the pre-cat sensor meaning that the catalytic converter isn't doing its job of burning excess fuel. The computer monitors the post-cat sensor and compares it to the pre-cat sensor. If the signals are similar, it assumes the cat is bad.
Thanks. Added to Porsche Acronyms List. Model to model they change, location to location too. I only mention the MAF possibility because suppose the ECU has some built in parameters that say at certain revs it should do thus based on the inputs it is getting from the MAF and the O2 sensors. If the characteristics of a different MAF give the ECU different readings at a certain airflow, then the ECU could get all confused and suggest the wrong air/fuel mixture. Any codes? Got access to any Porsche specific diagnostic hw/sw?