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Posts posted by whereswilbur

  1. Ok, today I replaced my coolant level sensor and the light is still flashing! I will get back out and check the fan. I also unplugged the MAF and the weird idle problem went away, could I have another faulty MAF? When I plugged my old one in the same fault came back. Im thinking a trip to the garage is required!!

  2. Hmm, okay. A couple of things. Your coolant lamp is blinking, which means you're very low on coolant - fill that sucker up before you run it again. The exhaust sounds doesn't sound quite right, do you have an aftermarket system on there? Finally, I have never seen a Boxster do that before, it's like it's hunting, but it's not. I would think vacuum leak or something affecting the vacuum of the system. I've got an article on troubleshooting vacuum leaks here: http://www.pelicanparts.com/techarticles/Boxster_Tech/21-FUEL-Vacuum_Leaks/21-FUEL-Vacuum_Leaks.htm . But, I think you may have additional problems. The car shouldn't do that on its own.

    Okay, I just saw that you have a 1998, the problem is most likely with the idle control valve, which is on the side of the throttle body. Sounds like the car is opening the valve and then closing it, trying to get the right metering of air. Maybe a vacuum leak afterall. The only way the car could be revving like that is if the ICV is opening and closing on its own.

    Not sure if this helps any...


    Thanks for the help, I will check the system tomorrow and see what I find. With regards to the exhaust, I think its original. I haven't replaced it myself at least. However it has only just started to sound different, maybe its on its way out? I have bought a new coolant level sensor as I have topped up the level but the light remains on. I hope I can get all my problems sorted or I will miss out on the Scottish summer time which only ever lasts about 5 minutes!!

  3. Ok, I'm still a bit stuck with my boxster problems, I have replaced my MAF, cleaned the ICV, checked for oil in the inlet tubing, checked for air leaks, but still have problems. This time however, my trouble is that the car is idling strangely. it will idle around 800rpm then rise to around 2000rpm on its own, before dropping back to 800rpm and just keeps dong this. any ideas? Thanks.

  4. As the topic says, what is AOS? I have read about problems with AOS, but have no idea what it actually is! Please help!


    Roughly speaking, the AOS (Air/Oil Separator) is the equivalent of a PCV valve on older cars.

    You can learn all you want to learn about the AOS by visiting Mike Focke's Boxster Pages, here: http://sites.google.com/site/mikefocke2/airoilseparatorreplacement

    Regards, Maurice.

    Thanks Maurice, a great help once again. :clapping:

  5. I have only just bought my 1999 2.5 boxster.....Total virgin when it comes to this car.....but when i accelerate hard, when i get to between 4000-5000rpm the engine strugles and holds back......as if a limiter had kicked in yet i have another 2-3000 rpm before it hits the red line......anyone have any ideas before i start replacing parts.......top speed that i have had out of it is only 125mph.....

    Regards Mike

    I have a similar problem with my 98 boxster. I have replaced the MAF (mass airflow meter) and cleaned the ICV (inlet control valve) which has helped a little. I also put a fuel treatment in when I filled up (I always use V-Power in my car). Also worth while seeing if your car is running any fault codes, if so post them on here and you will get all the help you need! Cheers, Dave.

  6. I'm in desperate need of a wheel refurb, and I think I will do them black. I think everyones taste will differ though, to be honest. Thing is, as long as the driver of the car is happy then who cares? And a bit of originality never hurts! Theres not many boxsters in my club regions that look like mine! :jump:

  7. 1. For a MY98 Boxster 2.5 liter - idle is 740 RPM + or - 40 RPM

    2. Basically they are the same - except eGas was added to the Boxster in MY00. The later style MAF has a 'Z' shaped passage that is supposed to reduce dirt and oil fouling. Your car can NOT be upgraded to the new style MAF (only MY00 on can).

    3. Your car's MAF is: 996.606.123.00 MAF. -- Nothing wrong with the 996.606.123.00 MAF - my car has the same MAF. This is the same MAF used on on 3.4 liter Carrera 2's until MY00.

    4. Yes, but the fault code(s) would help determine that - not all readers can read "pending" fault codes.

    My advice would be to do all the things I suggested in my first response to your question. Clean the throttle body, clean and check the ICV. Get the proper tools to check the MAF voltage.

    At this point I suspect a combination of these.

    Also, when you take the intake tubing off to clean the throttle body - not if there is oil in the throttle body. That would be a sign of an AOS failure.

    Thanks for your help Loren, I will get the hardtop off this weekend (the scottish weather is getting a little better!) and check all you have said. I hope I can avoid spending more ££££ on it as its cost me small fortune these last few months!


  8. Finally got a code reader on the car, but there is no codes stored on the ecu. I'm now beginning to wonder if I have the correct MAF fitted to the car. I replaced the MAF last year with one bought from ebay. When the car is idling it fluctuates between 800 - 1200 rpm. The Indy that serviced it form me had commented that the idle was a little high, but he was unable to get into check it as my roof wouldn't go down at that time due to another problem. However he found no faults stored the time either.

    So, my questions are -

    1. what is the correct idle speed?

    2. can anyone tell me if there is a difference between the MAF sensor on the boxster 2.5 / 2.7 / 3.2 / 996 ?

    3. what is the correct part number for the 2.5 MAF sensor?

    4. would an air leak cause this fault?


    Thanks in advance! Dave.

  9. I had a similar problem with my 98 2.5, the water was running down the overflow and all over the exhaust manifold. It took me forever to work out where it was coming from, what with the limited access and visibility in the engine bay. Anyway, I replaced the coolant bottle cap (for the latest version) and also the pressure relief valve and problem solved. Parts cost about £30 (GBP) from my local OPC. Hope this helps. Dave.

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