JayBr

Loren/JFP Thank you both for your comments. They're very helpful. I plan to take the car to another dealer to have them advise on the proper location of the sensor. It certainly not where JFP's diagram indicates. If I may ask one other point. Are either of you familiar with the "Recall campaign W737- deactivate speed setting 1 of the engine compartment blower"? I found this in the rennlist 997 forum but it didn't have a lot of commenting except that some members did receive a recall notice.

Thanks for the prompt reply Loren. So you agree with the dealership that in stage 1 the fan is always on and running and is the reason the fan starts and stops with each on/off ignition irrespective of the oil/coolant/outside air temp. What then is stage 2? This would seem to imply that once stage 2 is activated because of a >max temp determination a different fan speed then engages (?) and runs until the max temp is lowered. The fan then reverts back to the stage 1 speed and continues to run at that speed as long as the engine is running. I was unaware the fan is always on and never stops blowing air into the compartment while the car is running. The dealer and you are both saying this is the way the fan is designed to operate. Correct? I've owned three 911s (02 C4, 04 C4S and this 08 C4) with the M96 engine as daily drivers for the last 12 years. The first 2 911s which I drove for 11 of those years did not have a compartment fan that was always running. Do you know if the fan operation changed with the 997.1 M96?

This is a follow up to my engine compartment blower problem I described above and would appreciate some advice regarding what the local Porsche dealer advised after bringing the car in for service. Quite frankly I was surprised by their conclusion. The dealership agreed that the blower was operating continually when the ignition was on and never operating when the ignition was off. Once the engine has gotten past the initial morning cold start, the blower would go on and off every time the ignition went on and off irrespective of the oil/coolant temp at the time of turning the ignition on. Once on, the blower will stay on no matter what type if driving,( local stop and go, 80mph on highway, etc. ) The service manager advised the blower was operating within the designed parameters. (BTW he insisted the blower is an exhaust fan removing hot air from the compartment not blowing air into the compartment). He provided the following written description from official Porsche literature. (Sorry Its a bit lengthy but want to ensure you see the full description) "The engine compartment blower on the engine compartment lid is activated in two stages. Stage 1​ (permanent operation) is activated by the fuel pump relay as well as a change over relay and shutoff relay. Behind the fuel pump relay, a resistance lead (limiting the power to approx. 10 watts) leads to the engine-compartment blower via the shutoff relay. In stage 2, ​the engine compartment blower is activated directly by the Motronic control module via the change over relay and the shutoff relay (power approx. 33W) depending on coolant temperature, engine temperature and the ratio between intake and ambient air temperature. Stage 2 is also activated during sporty acceleration when detected by the Motronic control module. Once the temperatures fall below the respective temperature parameters, the engine compartment blower is set back to stage 1. If the engine compartment lid is opened while the engine compartment blower is active, the shutoff relay deactivates the engine compartment blower. After the engine is switched off , the engine compartment blower may continue to run or start to run. If no reduction of temperature is detected after 5 minutes of the engine compartment bower running in stage 2, the temperature display in the instrument cluster starts flashing. Additionally, a 'Failure - engine compartment blower" warning is displayed in the on-board computer. " After providing me this written document , the service manager advises the blower was working in accordance with parameters because: a) Under stage 1, the phase "permanent operation" means the blower can and will continually run at all times while the engine is running b) The is no set requirement for the blower to come on after ignition is off because the blower "may continue to run or start to run". This explains why it never comes on when the ignition is off. Also, since they believe the blower is operating within designed parameters, they will not examine any parts related to the operation of the blower. BTW there is no sensor in the position that JFP's picture depicts. I was told the sensor is between #5 and #6 and is inverted compared to JFPs pic so it's not easily visible looking into the compartment. Upon receiving the response, I was at a complete loss for words at the absurdity of this so I said goodbye and took my car home. The car is CPO'd and fortunately there are other Porsche dealers near by and will take the car to one of them armed with this dealers response and request confirmation. In the meantime, since I'm not a mechanic, could some of you please confirm my conclusions that this is absurd and I should pursue this with another dealer or is there somewhere in Porsche NA I could elevate this to.

08 C4 cab

I've looked for the sensor in the area you described and there is nothing between the intake manifolds for cylinders #4 and #5. Is it possible not even and sensor "holder" is there? Does a holder for the sensor exist? I'll take it back to Porsche and ask them to "test the sensor" for me. A little background on the car FYI. I purchased the car CPO'd in Dec 2015 when it had only 5k miles on it. After 3 weeks and 1k miles, the car had two problems I noted. One was the fan issue and the other turned out to be a badly scored #6 cylinder (excessive oil consumption and badly sooted left exhaust tip). In my concern about the cylinder issue symptoms, I failed to mention the fan issue when I brought the car in for service. As it turned out, Porsche replaced the short block under warranty and the car runs fine but I still have the fan issue. I did bring the car back for a summer tire change and it was then I was told the fan was operating normally. Given the lack of a sensor in the area you described, it seems to me it probably wasn't there at time of purchase and overlooked when the new block was installed. FYI, the purchasing Porsche dealership who CPO'd the car is different than the servicing Porsche dealership. So if correct, both dealerships missed the lack of sensor when doing some serious maintenance work. (CPO and a new short block). Thanks for your help.

JFP.... I have a 08 C4 cab. In my opinion, the engine compartment fan is not working as intended. After the engine is warm to normal operating temp and I turn engine off, when I restart engine, anywhere from 20 mins to 2 hours later, the engine compartment fan immediately comes on and if it's still on when I turn engine off again the fan will immediately stop. Once on and driving, the fan will stay on for anywhere from 5 mins to 1/2 hour or longer depending on type of driving, ie high speed or in traffic etc. This process will repeat itself everytime I stop and restart the engine until the engine has cooled overnight. First start in the morning does not start the fan but the on/off process will start with the first off/on ignition cycle I've described. The fan is never on when the ignition is off. Even if the fan is on when I turn off the ignition the fan will stop immediately. The Porsche dealership says this is normal but I have my doubts. I've owned a 02 C4 and an 04 C4S which have the same 996 engine as my 08 and never had this issue before now. Since your post has the engine fan's performance citeria in quotes, I'm assuming that you found the info in some authoritative source. Could you please provide that source to me and offer any comments you might have about this fan and how it's operating.

I'm looking at a 2007 cab s with a gray top. Any concerns regarding staining or general keeping clean problems with a gray top? Also, any comments about popularity of the gray top color as a resale issue?

Thanks Yoz. Any news of USA updates after the 8/08 release?

Im sorry but the information you have provided is incorrect... Part number 000.044.901.21 was Released in Aug 2008 and the Maps are from 08/2007... There are no Updated Map Packs since then, and the PCM 2.0 has been completely phased out. That means there will be no more Map Updates... no 2009 Version.... Does anyome know if there will be any updates after the '08 release of the '07 maps?

I have a 2002 C4 Cab with 65k miles on the clock. The car has been an every day driver since I purchased it in 2004 as Porsche certified car with 14K. At 25k I had an RMS repair and new clutch as well. The RMS portion was covered under warranty. Until now I've never had any other significant problems and always had the car maintained at a Porche dealership. I now have a second RMS failure at 65k. Since I thoroughly enjoy the car, I want keep it beyond 100k if I can. I'm willing to spend the bucks to have Porsche do the RMS work and gain the benefit of a two warranty for the work. The question is how much work should I get done? Aside from the RMS, an intermediate shaft seal and a new clutch, what about a new flywheel, intermediate shaft bearings, support studs and flange? I'm not technically savy enough to recognize their wear life. Considering I want the car to last a lot longer and have had no real problems with the car, at 65k is it smart to replace them as well or a waste of money? Any advice would be appreciated. JayBr