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Hi Guys, excellent thread and extremely helpful. I have a 2013 Cayenne S and I'm getting the exact same series of errors which are PSM failure, check engine light and start stop deactivated. I will monitor the battery voltage as suggested above. The error code appears to be a misfire on cylinder four and so I too am going to look at changing out the coils and the plugs.
****My question is this, is it necessary to disconnect the battery when doing coil and plugs? If so, how do I go about doing that efficiently… Apologize as this is not my area of expertise
Last edited by dschaaf68; Sep 27, 2023 at 08:00 AM.
Well I just replaced all the coils with BERU OEM replacements for good measure. I didn't like the look of the spark plugs that were replaced 8000miles ago so I decided to replace them with the same Bosch units. Has anyone got a picture of their plugs after similar mileage?
I would also love some feedback on iCarscan diags for Misfire and Cylinder Roughness. After replacement of Coils and plugs:
Misfire_current trip = 0
Misfire_10 trips = 3 (Cylinder 7)
Engine roughness cylinder = All over the place for all cylinders. Very high and very low values changing every constantly. The reference value is around 65000 whatever that means.
Cheers,
Tim
Hi,
I recently bought a 2013 GTS with similar issues: CEL, PSM failues, auto start/stop deactivated.
I replaced all coil packs with BERU and spark plugs with bosch. So far after the replacement, I have driven ~30 miles only in 3 different days and all is good.
Here's a ppicture of old vs new spark plugs, but I don't know how many miles were on the old spark plugs.
old vs new old spark plug
Originally Posted by dschaaf68
Hi Guys, excellent thread and extremely helpful. I have a 2013 Cayenne S and I'm getting the exact same series of errors which are PSM failure, check engine light and start stop deactivated. I will monitor the battery voltage as suggested above. The error code appears to be a misfire on cylinder four and so I too am going to look at changing out the coils and the plugs.
****My question is this, is it necessary to disconnect the battery when doing coil and plugs? If so, how do I go about doing that efficiently… Apologize as this is not my area of expertise
This is probably not the best way to answer your question but I did not disconnect the battery and had no issues.
Richard - some people consider them a service item. Porsche doesn't. So far - knocking on oak-grain-formica(tm) - mine are original at 75,000 miles ('11 CTT). Coils may be damaged if plugs aren't changed on schedule. A wider gap on a plug requires higher-voltage to fire, which in turn increases the current through the coil, and in turn that cause the coil to run hotter.
If you do replace all the coils - do the plugs at the same time. It will never be easier to do.
As far as the multiple faults - first thing I check if I hear that is the battery voltage. If you're still running the original battery it's likely on borrowed time. The modules in the vehicle will shut themselves down to protect themselves against a "brown-out" low voltage damage scenario. When they do that they often store all sorts of codes - mostly bogus.
You can display the battery voltage on the MFD in the dash under the vehicle section. Make it a line-item for a while. Watch the voltage during cranking. If it drops down to 10V or so - the battery is gone. Then watch the charge voltage. Running down the road, not too many current eaters on - you can expect to see 13.3-13.7V in non-sport mode. In sport mode it will jump up roughly one volt to around 14.3-14.7V. That's normal behavior. If you see otherwise - let us know what you see.
And yes - the ECU does shut down a non-firing cylinder. It turns the injector off so the cylinder doesn't get fuel-washed by unburned fuel running through it. That's a bad thing since it washes the oil off the cylinder walls..
Thanks very much for the information. When testing out the battery it seems to stay right at 14.2 V when running down the road whether I am in sport mode or non-sport mode. I am running the air conditioning as it is still quite warm here. When I started up, it seems to be in the 12.2 V 12.3 V range.
I too am going to look at changing out the coils and the plugs. ***My other question is this, is it necessary to disconnect the battery when doing coil and plugs? If so, how do I go about doing that efficiently… Apologize as this is not my area of expertise
Hi,
I recently bought a 2013 GTS with similar issues: CEL, PSM failues, auto start/stop deactivated.
I replaced all coil packs with BERU and spark plugs with bosch. So far after the replacement, I have driven ~30 miles only in 3 different days and all is good.
Here's a ppicture of old vs new spark plugs, but I don't know how many miles were on the old spark plugs.
old vs new old spark plug
This is probably not the best way to answer your question but I did not disconnect the battery and had no issues.
Hi guys,
Here's a fun one for you. It's a bit multi-faceted so I was thinking of starting a new thread, but it seems to be exactly what this conversation is all about.
I am having very similar issues with my new-to-me 2013 GTS currently with a bit less than 58K miles on the clock. I have had it exactly a week when I was calmly cruising down the highway yesterday afternoon and I got the PSM failure and Check Engine notifications on the screen along with a rough engine and loss of power.
I got it home, shut it off and got my iCarSoft POR 2.0 scanner from the back. I restarted the car and it had no warnings and ran normally.
Anyway, checking the DTCs the scanner reported:
P2311 - Ignition Coil D Secondary Circuit
P0354 - Ignition Coil D Primary Control Circuit open
P0402 - Invalid Data Received From TCM
P0304 - Cylinder 4 Misfire Detected
After reading through this thread it looks like I got a bad coil on cylinder 4. However, I want to ping you guys about a connection to a low/bad battery situation.
I ran some voltage tests and I was getting 12.0-12.1v when the car was in accessory mode. When I cranked the engine over the voltage dipped down to 8.0-9.1v. While running the voltage crept up to about 14.2v.
I have the complete Porsche shop service history on the vehicle since new and apparently there was an entry from January 8th of this year @57K miles that reads: C/S Auto start stop does not work consistently. Will turn off engine sometimes and not other times. Please check. The action taken was that "vehicle battery was low causing auto start/stop function to not work. will require replacement of the battery. not covered under extended warranty. customer declined repair at this time."
SO, is it he chicken or the egg? Did the weak battery fry the coil? I am a bit mystified as (according to the service records) there was a new battery installed by Porsche in August of 2022. Do Porsche batteries go bad after 18 months? The battery cranks the car over just fine, I have no sense of a dead/weak battery when I turn the key. Could there be some other electrical gremlin?
On that same service from 8/22 there is an entry: C/S Check engine light came on, vehicle feels sluggish, please check. Dealer response: "verified the check engine light is on checked for faults and found the bank 1 had misfired in all 4 cylinders on that bank. i found that the hydraulic valve for valve lift adjustment had failed. I removed the vacuum pump and replaced the hydraulic valve. i replaced the o rings on the vacuum pump. i verified the vehicle is running normal now. the misfires are gone. i road test the vehicle at 3:08 returning at 3:32 on 9/14/2022. i then inspected the vehicle for leaks and found none."
Another fun fact from service records: On a 10/28/2020 service @ 48K miles, there was an entry that read: C/S Check engine light, PSM failure message and auto start/stop deactivated message comes on. Check engine light is there all the time and the other warnings only come on sometimes. Please check. Dealer response: verified check engine light is on. checked for faults and found ones for cylinder 5 misfire and cylinder 5 ignition coil shutdown. inspected all coils and rec replacing just cyl 5 ignition coil. replaced ignition coil.
So it appears this has happened before and my guess is that this will keep happening to all the coils.
What do you guys think?
Should I grab a new battery and a coil or two for a spare or maybe just replace them all as I'm in there? Spark plugs were done 8K miles ago, so I am not planning to change them.
Seeing as nobody responded to this old thread, I ended up buying both a new battery and four coils for the left side bank (cyls 1-4). Misfires gone and the battery feels much more healthy. I will get coils 5-8 done asap just to get a fresh set across the board.
Last edited by skidpalace; Apr 26, 2024 at 08:46 AM.
Seeing as nobody responded to this old thread, I ended up buying both a new battery and four coils for the left side bank (cyls 1-4). Misfires gone and the battery feel much more healthy. I will get coils 5-8 done asap just to get a fresh set across the board.
Yup, classic faulty coil. When it happened to me I replaced all the coils with the latest part number and saved the good leftovers. I put a known good coil in the spare tire well just incase it happens in the middle of a road trip.
very helpful thread. I had exactly the same issue. PSM light and CEL. Engine misfire on cylinder 4 and 8 on a 54k mile 2015 CTT.
No Maintenace history when i bought thru BAT auction 3 mths ago.
Replaced battery, and all 8 plugs and coils.
No more issues.
i suspect since plug service is supposed to be every 30k, that the older plugs combined with 9 yr old battery caused the coil failure. Lesson is replace plugs every 30k miles and don't let your battery go 9 yrs.
Very useful forum post with lots of information, thanks!
I bought a 2011 CS 6 months ago with 127K km (~79K miles), 3-4 months ago started getting PSM Failure / Reduced Engine Power / Auto stop-start disabled messages, but no CELs. These would show up either after power-washing the car or some hard driving, but not very consistently.
These would go away on next start up. My suspicion was battery-issues but as the car was new-to-me I decided to do a list of maintenance items/general TLC and then re-assess.
First CEL I got was P0303 Misfire cylinder 3. I replaced all 8 plugs - I suspect the plugs I pulled out were stock but not 100% sure.
Car drove fine for a while, still had a few things on the TLC list, including eventually coils.
A few days ago had 5 codes show up, including Reduced Engine Power message:
P0303 - Cylinder 3 misfire
P0076 - Intake Valve Control Solenoid Circuit Low Bank 1
P0302 - Cylinder 2 misfire
P0304 - Cylinder 4 misfire
P0300 - Random/multiple cylinder misfire detected.
I have ordered 8 new ignition coils after reading this forum and the other one highly suggesting them.
I will keep the P0076 code in the back of my head in case I continue to get messages after replacing the coils, and will report back here. The cylinders were all on Bank 1 so not sure if this was caused by the solenoid, coils, battery, or timing chain. Timing chain is also on the list in the next 6 months or so.
Battery consistently shows 14.3-14.5 V, I use the car in Sport mode so don't use Auto Stop-Start. I suspect battery may be OE too so this is also on the list at some point - but this also means the battery is 14 years old...
Very useful forum post with lots of information, thanks!
I bought a 2011 CS 6 months ago with 127K km (~79K miles), 3-4 months ago started getting PSM Failure / Reduced Engine Power / Auto stop-start disabled messages, but no CELs. These would show up either after power-washing the car or some hard driving, but not very consistently.
These would go away on next start up. My suspicion was battery-issues but as the car was new-to-me I decided to do a list of maintenance items/general TLC and then re-assess.
First CEL I got was P0303 Misfire cylinder 3. I replaced all 8 plugs - I suspect the plugs I pulled out were stock but not 100% sure.
Car drove fine for a while, still had a few things on the TLC list, including eventually coils.
A few days ago had 5 codes show up, including Reduced Engine Power message:
P0303 - Cylinder 3 misfire
P0076 - Intake Valve Control Solenoid Circuit Low Bank 1
P0302 - Cylinder 2 misfire
P0304 - Cylinder 4 misfire
P0300 - Random/multiple cylinder misfire detected.
I have ordered 8 new ignition coils after reading this forum and the other one highly suggesting them.
I will keep the P0076 code in the back of my head in case I continue to get messages after replacing the coils, and will report back here. The cylinders were all on Bank 1 so not sure if this was caused by the solenoid, coils, battery, or timing chain. Timing chain is also on the list in the next 6 months or so.
Battery consistently shows 14.3-14.5 V, I use the car in Sport mode so don't use Auto Stop-Start. I suspect battery may be OE too so this is also on the list at some point - but this also means the battery is 14 years old...
Batteries need replaced around 50k or so. A degraded battery will cause your coils to wear out, which normally they are a lifetime item. Have an indie shop replace your battery, since you've already had coil and plug issues.
Hello, I am possibly facing the same issue as you all experienced.... But am eager to know how to use PIWIS 3 for this, I tried hard but I have no clue how to deal with PIWIS..... I am a former e46 owner used to use diagnostic tools a lot . But I really can't deal with this PIWIS.
Car is 958 Cayenne S ´11 and my symptoms are:
Long crank
PSM light
disabled start stop
rought idle (Skoda fabia owners would not consider it as rough )
yellow CEL light (not every time)
Just because I know, that our engines eat coils and spark plugs like hell, I assume that this is my problem too, but how do I actually confirm it with PIWIS? I tried every module "fault finding" but did not get any relevant answer. I did not start engine tho. Can somebody help me please? How do I find misfire logs?
. But I really can't deal with this PIWIS.
