Misfire on cylinders 123 - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Glosboxster · 06-25-2017, 05:23 AM

Please can someone assist me with misfiring Boxster 2.7 year 2000.

Went from running fine to (according to my cheapo analyser) a multiple cylinder misfire detected issue in. Scroll down and it tells me I have a misfire on cylinders 1 2 & 3.

Now all this happened within me slowing for a junction then applying the power.
Juddering, misfiring, spluttering and backfiring.......all in an instant.

So far I have fitted new plugs so that rules them out.....to be honest it is unlikely that all three plugs would fail at once.

Is there a single common component for these cylinders I should be looking at that would cause this issue

Thanking you for any assistance.

jsceash · 06-25-2017, 05:54 AM

On a 2000 I would suspect a timing solenoid ramp wearing. You could verify this a little better with a Durametric tester. If you don't have that available get the car to a local dealer or indy sport car shop

AZ986S · 06-25-2017, 08:42 AM

I just went through this. What exactly are the codes?

One thing to check before anything would be your camshaft deviation values.
High values could indicate variocam worn ramps (as mentioned below) or more serious issues. If you are getting Misfires for those particular cylinders (1-2-3) on one side only, then I it could be O2 sensor on that side, or maybe a camshaft position sensor. I had issues with multiple cylinders not just on one side. I ended up replacing all 3 hydraulic chain tensioners as well as all 6 coil packs since a couple were bad. One of the spark plugs was loose too, so that also was a contributing factor. I've had similar misfire issues before and I cleaned the MAF sensor and went away. I doubt all 3 coilpacks went bad at the same time. Vacuum leak maybe? AOS?

Have you upgraded the IMS bearing? Don't drive it until you have fixed the problem.

Glosboxster · 06-25-2017, 10:53 AM

Thank you for the replies guys. Appreciated.
I have managed to get rid of the back firing by swapping around with some old coil packs I had in my workshop. Also double checked plugs were tight.
I also am no longer getting a fault code?
However........it idles sluggishly and still not revving clean at all. Splutters before she picks up on the revs. Almost feels like I have a pipe off somewhere that sort of feeling. Seems to rev clean when she is at high revs.

Will replace o2 and camshaft sensor and clean the MAF and if that doesn't cure it then it's a trip to the Porsche garage.

I will also take your advice om IMS bearing!