Engine light flashing rough running

[Boxsum]

Good evening everyone 

Took boxster out for run this afternoon  and out of the blue engine light started flashing and engine started running a bit rough. Nursed it home as wasn’t far. Have no code reader and certainly wouldn’t drive it anywhere as it is ? Any ideas ? Car was serviced just a few weeks ago at SCS Porsche with obviously nothing picked up. Was running perfect. Coil packs? Maf sensor? 
 

Any thoughts? 
Thankyou 

Edited November 27, 2023 by Boxsum

[markjh]

 

My thoughts - FWIW:

The car really needs diagnosing properly, (unfortunately) the first step is to get any codes read, which will hopefully point you in the right direction. Other alternative is to start playing a game of random part replacement lottery, which is frustrating and expensive.

Would suggest you call SCS with a view to taking it back to them, see what they suggest if they've recently had it in.

PS - on first read I thought you said you had a blue flashing engine light, which would have been a new one..😀

[Nobbie]

I had similar recently after I’d not driven for a couple of weeks. My code reader diagnosed a misfire on Cylinder 3 which I put down to a dodgy coil pack getting some damp in the cracks while it was sat. The next day it started without a light, but didn’t seem right, so I drove it gently until fully warmed up and then left it. I think this cleared the damp and it’s been fine since. Could also be a loose connector on a coil pack. I had this a few weeks after changing them myself, but obviously didn’t push the connector home.

[½cwt]

I think you are looking in the the right place with coils and MAF.  Easy test is un plug the MAF and see if the fault goes away and the engine runs OK on its default mapping. Coils could have become damp in the recent moist cold weather and be causing a misfire.  A basic code reader will let whether the same cylinder or multiple misfires.  Same cylinders would be the relevant coils, multiple the MAF.  It can also be lambda related but these tend to give a constant EML fault.

When my MAF failed 4 years ago I got a second hand one which is still running fine, about £30 from the various breakers.  A new Bosch one (who supplied the originals to Porsche is around £80 and one from Porsche is silly money.  There are two types, the very earlier ones have a part number 996.606.124.00, later 996.606.125.00 which up issued to 996.606.125.01 or Bosch 0 280 218 055.  You also need a Torx bit with a hollow tip to remover the old one and the outboard screw is a bit tricky to get at.  Coil packs, if required, are Beru ZS178 which are the up issued OE item.  About £18 from Autodoc on the right discount day.

[Boxsum]

Thankyou everyone.

The engine light flashed up intermittently then stayed on. I will have a look for cracks on the coils tomorrow. Am I right in thinking the coils could still play up if not cracked? 
 

[½cwt]

8 hours ago, Boxsum said:

Thankyou everyone.

The engine light flashed up intermittently then stayed on. I will have a look for cracks on the coils tomorrow. Am I right in thinking the coils could still play up if not cracked? 
 

You'll need to take them out to get a good look at them unless you have a ramp to get a good look from underneath.  The cracking can be almost microscopic with moisture getting in by capillary action.

[Boxsum]

Update!

Codes read: As follows 3 stored,

1. P0300 Random / multiple cylinder misfire 

2. P0301 Cylinder 1 misfire detected 

3. P0304 Cylinder 4 misfire detected 

 

Does this now point to anything obvious please ?

 

Thankyou 

[½cwt]

Either 1 and 4 coil packs, at the front so most exposed to the road, or MAF.  A lamdba would be only on one bank normally.  I'd go with disconnect the MAF and see if it runs clean as the first step, if nothing else saves jacking up the car taking wheels off and crawling underneath!  Although you do have to get the roof to service position and take the top cover off.  MAF is passenger side toward the back of the side of the engine bay, check on YT video.

 

[Nobbie]

When you clear the codes, do they come back? I think I would be letting it idle with the occasional rev to come upto temperature to help drive off the moisture and then let it cool before checking if the issue is still there before getting into removing the engine cover etc. If this solves it, then it does strongly point to coil packs. When were they last changed?

[iborguk]

Coil packs.

[Boxsum]

1 hour ago, Nobbie said:

When you clear the codes, do they come back? I think I would be letting it idle with the occasional rev to come upto temperature to help drive off the moisture and then let it cool before checking if the issue is still there before getting into removing the engine cover etc. If this solves it, then it does strongly point to coil packs. When were they last changed?

The coil packs are the original ones as far as I’m aware as is the MAF sensor 

 

[Boxsum]

Thankyou everyone I will do as suggested when I have time and report my findings 

[Boxsum]

4 hours ago, ½cwt said:

Either 1 and 4 coil packs, at the front so most exposed to the road, or MAF.  A lamdba would be only on one bank normally.  I'd go with disconnect the MAF and see if it runs clean as the first step, if nothing else saves jacking up the car taking wheels off and crawling underneath!  Although you do have to get the roof to service position and take the top cover off.  MAF is passenger side toward the back of the side of the engine bay, check on YT video.

 

I will have a look tomorrow if I can.

So if I look at the coils am I understanding 1 and 4 are the front ones either side? 
 

Thankyou 

[½cwt]

19 minutes ago, Boxsum said:

I will have a look tomorrow if I can.

So if I look at the coils am I understanding 1 and 4 are the front ones either side? 
 

Thankyou 

Yes.

Probably worth doing the coil packs anyway under £100 from Autodoc.

[Everywhen]

15 hours ago, Boxsum said:

Thankyou everyone.

The engine light flashed up intermittently then stayed on. I will have a look for cracks on the coils tomorrow. Am I right in thinking the coils could still play up if not cracked? 
 

Yes, my coil packs looked fine, yet No:3 had a misfire, changed the coil pack and the fault went away. I changed all 6 obviously.

[Boxsum]

Ok, I cleared the fault codes this evening and then let the car idle till up to temperature then drove it up and down the drive a few times. It seemed to run fine. Checked for codes again and none stored, all clear. 
I guess if it’s running fine I’m not at this point going to find anything out by unplugging the MAF sensor, so from what has happened does this tend to lead to the coil packs?

I will take it out for a drive in daylight tomorrow to see if the problem reoccurs 

 

 

[½cwt]

The MAF will cause problems in all conditions, so coil packs.  Get 6 from Autodoc, BERU ZS178 is the one you need.

Edited November 28, 2023 by ½cwt

[Nobbie]

3 minutes ago, Boxsum said:

Ok, I cleared the fault codes this evening and then let the car idle till up to temperature then drove it up and down the drive a few times. It seemed to run fine. Checked for codes again and none stored, all clear. 
I guess if it’s running fine I’m not at this point going to find anything out by unplugging the MAF sensor, so from what has happened does this tend to lead to the coil packs?

I will take it out for a drive in daylight tomorrow to see if the problem reoccurs 

 

 

Yes, that would tend to point at old coil packs getting damp in them. When you said they were original, I assume you mean just in your ownership rather than from new😬. Mine are about 8 years old, so they’ve had a fair run.

[Boxsum]

17 minutes ago, Nobbie said:

Yes, that would tend to point at old coil packs getting damp in them. When you said they were original, I assume you mean just in your ownership rather than from new😬. Mine are about 8 years old, so they’ve had a fair run.

I’ve had the car for 12ish years and never been done in my ownership so can’t grumble if they are the cause. 
Interesting day ahead tomorrow! 

[Boxsum]

BTW any top tips on changing them ie get engine warm first or not etc etc to help bolts come out? 
 

Thanks once again to everyone👍
 

[Boxsum]

40 minutes ago, ½cwt said:

The MAF will cause problems in all conditions, so coil packs.  Get 6 from Autodoc, BERU ZS178 is the one you need.

Any ideas? Don’t want to get the wrong ones?

[½cwt]

They are the one. The part has been up issued by Porsche from the ZS177.  If you ask Porsche for a coil pack for an early 3.2 coils pack you will get a Beru ZS178 but in a very expensive Porsche box!  You won't get a ZS177.  I removed ZS177s from my 2000 3.2 S earlier this year and fitted ZS178 and they are fine. They come with new bolts in the box so don't worry about different bolt lengths.

[Boxsum]

44 minutes ago, ½cwt said:

They are the one. The part has been up issued by Porsche from the ZS177.  If you ask Porsche for a coil pack for an early 3.2 coils pack you will get a Beru ZS178 but in a very expensive Porsche box!  You won't get a ZS177.  I removed ZS177s from my 2000 3.2 S earlier this year and fitted ZS178 and they are fine. They come with new bolts in the box so don't worry about different bolt lengths.

Ok Thankyou 

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

[Nobbie]

2 hours ago, Boxsum said:

BTW any top tips on changing them ie get engine warm first or not etc etc to help bolts come out? 
 

Thanks once again to everyone👍
 

Probably do it with a cold engine, but spray plenty of plus gas on the bolts and leave a while. You need to be very careful not to round off the Allen bolts or it will be a world of pain getting them out. Make sure the Allen key is fully home before attempting to turn by tapping in with a small hammer. Good luck.

[Mattman42]

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