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Ahsai

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Everything posted by Ahsai

  1. Ahsai
    Actually based on your latest logs, I'm not sure it's a single cylinder issue anymore (there were misfires on cyl 2 & 3) so I doubt a leak down test will reveal anything. May want to just drive it with the MAF unplugged for 1/2hr or so. The performance will be reduced but at least you can feel if it helps the rough idling. Your cam deviations look excellent so I doubt IMS and cam padding are the issues. BTW, the AOS on your car (MkII) uses a rubber hose and not a bellow.
  2. Ahsai
    Btw, also check the variocam+ and intake valve lift control solenoids. Two on each cam cover. There's a metal bracket with rubber seal on each one. They need to be air tight. Air leak here will cause misfires.
  3. Ahsai
    Very interesting data and I don't think I have any conclusion though. Now I'm not so sure it's a single cylinder issue. In the 1hr file, you got some misfires on cyl #2 and #3 @ 2k+ rpm. In general cyl #2 rough running has more variation than other cylinders. In the 1 min file, the idle rpm varies quite a bit and cyl #1 has the highest rough running variation. I assume you feel rough idling during that time? Going back to what John (JFP) was saying about the MAF, did you ever try to clean the MAF? Also, will the rough idle disappear if you disconnect the MAF?
  4. Ahsai
    Leak down and compression tests are best done by pros if you're not familiar with those. Basically the test will reveal if the cylinders are more or less the same in terms of compression and sealing capability. If one cylinder has a very different number than the others, clearly that cylinder has a problem. If those tests check out, the next step may be the fuel injector.
  5. Ahsai
    Ideally, it would be good if you can drive the car until the engine has been fully warmed up (about 1/2hr of driving). Then do a log for steady idle for a couple of minutes (assuming the rough idling occurs). For reference, I have a stock '03 996 and a '02 3.8L LN nickies 996. Both have the rough running values for all cylinders close to 0.2~0.3 most of the time and from time to time jump to +/- 0.6 per second^2. So it seems all your cylinders have numbers close to the numbers above except cylinder 2.
  6. Ahsai
    36s of idling here (time from 15:20:41.27 to 15:21:16.82). Red is cylinder 2 (per your second spreadsheet heading). You can see clearly all the other cylinders are approx +/- 0.8 per second^2 I wonder if you should do a leak down and compression test on all cylinders to compare them. If the numbers are OK, maybe replace the cylinder 2 injector? plots.pdf
  7. Ahsai
    In your second spreadsheet, the rough running columns are in the order 1, 2, 3... The typical order is 1-6-2-4-3-5 (firing order). Did you reorder the columns or change the title? Second spreadsheet column G says Rough running cylinder 2. It has higher variations and magnitude than any other cylinders at idle.
  8. Ahsai
    In this excel file, did you start with the engine already fully warmed up? Or the first row begins with a cold start?
  9. Ahsai
    Check fuses C1 to C4 and E1. Also bypass the clutch interlock switch is you have one. Try another key. If not those, it's likely the ignition switch then.
  10. Ahsai
    The first video is the SAI pump. Needs lubrication or replacement. I can't hear the noise you're talking about in the second video.
  11. Ahsai
    1) from memory, only one sensor in the front and one in the rear, each connected to the control arm via a plastic arm. 2) not sure 3) there are no other sensors. My guess is this sensor only compensates for the passenger load of the car so the adjustment may be relatively small and difficult to notice
  12. Ahsai
    Got you. If the above doesn't work, you may need to reopen the cluster and retrace all your steps. Maybe something inside has been disturbed.
  13. Ahsai
    I take that those gauges swing to their full range when tested by the Durametric? The next thing to try is remove fuse B1 and reinstall it. If that doesn't work, I suggest you remove all the connectors at the back of the gauge and reconnect them.
  14. Ahsai
    Are you sure all the connectors at the back of the cluster are fully plugged in? Do you have a Durametric? It can test the cluster.
  15. Ahsai
    That's great to hear.
  16. Ahsai
    That's good. I'm more worried about the cylinder side because small debris may get stuck between the piston crown and the cylinder wall above the top ring.
  17. Ahsai
    Btw, may be a good idea to examine all the cylinders and valves very carefully and make sure the debris didn't spread to other cylinders.
  18. Ahsai
    I'm glad you found the culprit!
  19. Ahsai
    I used this tool to verify TDC compression based on the firing order when I rebuilt my engine. This will catch all gross timing errors. https://www.amazon.com/Innovative-Products-America-7894-Compression/dp/B000TQ16HG
  20. Ahsai
    Intake air leak should give you bad idle (which you don't have). Any error code? Take a look here for fuel filter replacement http://www.pelicanparts.com/techarticles/Boxster_Tech/04-BASICS-Fuel_Filter/04-BASICS-Fuel_Filter.htm
  21. Ahsai
  22. Ahsai
    Some more thoughts...Is your new MAF from Bosch and does it have the correct p/n? Any non-Bosch non-genuine MAF is problematic. How are your engine air filter and fuel pressure filter? Any massive intake air leak?
  23. Ahsai
    The relay is under the rear parcel shelf, left side. Also a couple of high current fuses there, if you call that the auxiliary fuse panel :)
  24. Ahsai
    I can see that. The price I mentioned was just for a reliable build for DD. A track-ready engine will be more $$$.
  25. Ahsai
    If the debri on the exhaust valve was not from the intake side, is it possible it's sucked in from the exhaust side e.g., a loose piece from the cat? May be worthwhile to check to avoid reoccurrence.
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