Engine light flashing rough running

[½cwt]

3 hours ago, Boxsum said:

Ok Thankyou 

So just out of interest wether it’s a 2.5 boxster 986 or even a 997 they are all the same ? 
 

They are interchangeable.  Technically the ZS177 was used up to 2002 models and the ZS178 form 2003 onwards and then on the 987.1 as well.  ZS177s cost 2 to 4 times the later versions though.

[Paul P]

On 11/28/2023 at 9:07 PM, Mattman42 said:

Had similar issues and codes on my mk1 TT and it was the coil packs. They looked fine to the eye but a common problem. Easier to swap on the TT though I suspect

I did 180k miles in an a4 over a 13year period.  By comparison with other parts it ate coil packs.  At one point audi swapped them all out as a free “good will” when it was in for a mot.  Must have had a dozen over the time.  Typically I would go over a bump or a pot hole and then misfire and cel.  
 

i ended up carrying a couple a spares.   Last time it digested one I was back on the road in less than 10 mins.  
 

as you say.   Easier on the TT or indeed the A4 and for sure the Boxsters seem to be much less prone to them failing than my a4 was.  

[charlieboy2608]

While your there it would be prudent to change the spark plugs unless you historically have their change date....

[Boxsum]

6 hours ago, charlieboy2608 said:

While your there it would be prudent to change the spark plugs unless you historically have their change date....

Thankyou but they were not long done on its service

Edited November 30, 2023 by Boxsum

[½cwt]

Unless you are doing high mileage, change plugs on condition not age and mileage, unless you want to chuck money away that is. What 8t is worth doing is listening and re tightening them periodically. You don't want a seized spark plug....

[Boxsum]

New coils fitted this afternoon now purrs like a kitten! 
Thankyou for everyone’s help👍🙏

Even cleaned and polished the wheel barrels before refitting the wheels😊

Just to note the front 2 coils only had the tiniest of hairline cracks barely noticeable. The others look perfect , TBH they all look fairly new although I know  there not as owned the car for well over 12 years. Was quite surprised! 
I possibly may post a picture of one tomorrow. 
 

[Boxsum]

Finally had time to upload these. 
These are the front 2 that were causing the misfire. 
Quite surprised how little cracks can cause an issue, the other 4 look perfect but replaced all 6 anyway.

Is there anyway of knowing how old they are by the part numbers? I’ve had the car over 12years and never changed in my ownership.

 

 

[iborguk]

Right hand two digits on parts tend to be the revision, so at 00 I’d say the cars had its money’s worth out of them.

[Fat Rat]

Agree with above. I cannot even see that part number in the parts listings I have dated 2017. Early coils are listed as 99760210700 with revision 02 with later engine having 99760210402, not listed but I know has a revision of 04. It does throw up another totally different number for all engines 90038502501. At least they were Porsche parts and Defo have done well. Sure Chris will tell us more. 😉🤙🏻

[½cwt]

2 hours ago, Boxsum said:

Finally had time to upload these. 
These are the front 2 that were causing the misfire. 
Quite surprised how little cracks can cause an issue, the other 4 look perfect but replaced all 6 anyway.

Is there anyway of knowing how old they are by the part numbers? I’ve had the car over 12years and never changed in my ownership.

 

 

Being 997 part numbers they'd be from 2005 at the earliest.

 

Default would be to swap with BERU ZS178 (BERU is the OE supplier to Porsche) which are the Porsche up issued part, if you look up the original 996 part number 996 602 102 00 until 2002 they point to the BERU ZS177 which is about 3 times the price, but still a third of the Porsche price!  The bolt holes are the same depth as the head of the coil (they come with new longer bolts in the box) and are less prone to the cracking shown.  Although the torque is very low for the retaining bolts, only 10Nm, so I suspect some of the cracking is overtightening after plug or plug tube O-ring changes.

[Boxsum]

7 hours ago, ½cwt said:

Being 997 part numbers they'd be from 2005 at the earliest.

 

Default would be to swap with BERU ZS178 (BERU is the OE supplier to Porsche) which are the Porsche up issued part, if you look up the original 996 part number 996 602 102 00 until 2002 they point to the BERU ZS177 which is about 3 times the price, but still a third of the Porsche price!  The bolt holes are the same depth as the head of the coil (they come with new longer bolts in the box) and are less prone to the cracking shown.  Although the torque is very low for the retaining bolts, only 10Nm, so I suspect some of the cracking is overtightening after plug or plug tube O-ring changes.

The new beru ones were metal sleeved in the fixing holes maybe to help prevent this? 

[½cwt]

1 hour ago, Boxsum said:

The new beru ones were metal sleeved in the fixing holes maybe to help prevent this? 

The shorter holes are sleeved too.  Must be a reason they changed them to add material (and cost) it is usually the other way...