Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

Rough running and CEL

DucatiRob

Well-known member
Joined
22 Jul 2015
Messages
2,236
I have had this issue on and off since fitting a dual cone air intake system to suit the wing/deck lid I have fitted. Prior to my engine being rebuilt by Hartech the problem seemed to have settled down except for being a little fluffy around 2000 rpm, and the power curve being a little peaky. I know that I need a remap but prior to the engine rebuild was not a good time and now I need to run it in before I can get it to Wayne at chipwizards!

The engine has generally been running well since the rebuild (5 weeks), I had one instance about a week after collecting it where it began to run a little rough and misfire, the CEL came in briefly then disappeared and after 10 mins or so it was back to normal! Until Sunday it has been fine, then I had exactly the same issue except the CEL came on and stayed on.

I connected my cheap OBD Bluetooth/torque App. and got the following error codes:

P2180 System Too Rich Off Idle Bank 2
P0300 Random Multiple Cylinder Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0304 Cylinder 4 Misfire Detected

I have cleared the error codes and driven it once, apart from seeming to be a little rough at first it was fine and no more CEL or error codes.

I am going to speak with Hartech as when I picked up the car Grant did mention I might see the odd CEL, I should have asked him why this might be, maybe just the ECU settling down after everything being disconnected!

Interesting that the cylinder misfires are on the two cylinders that were scored, can only imagine that this is a coincidence! I am fairly sure the issue is down to the air intake, combined with topgear exhaust and new headers, but I want to make sure everything else is ok before getting it re-mapped in the next month or so.

Will be checking for any air leaks in the air intake, MAF being contaminated etc! Wondering if there is a possibility of the Cats breaking down, any way to check this? Anything else I might check?

Thoughts and input appreciated!
 
Sorry to hear the problems keep coming!

I'm sure someone else had some issues with the Top Gear exhaust recently - rough running or cel I can't recall.
Best of luck sorting.
 
I have a theory with some exhaust mods causeing problems while others dont seem to ..

My idear is that there was an existing problem which the mod has made more obvious .

Your fault codes could easily lead down 2 different pathes .. misfire being one route and too rich on B2 being another .

I have a hunch with no real basis but something i would like proved first on this is that the high lift solinoid bank 2 is ok .. either a replacement or just swop bank to bank as this will transfer the fault to the other side .

There is no actual Porsche fault code for this solinoid fault and different testers tend to give different codes .. mine at work always gives a lambda swoped code but on here ive never seen that although many people have proved the solinoids to be faulty.

Over rich .. hmm .. maf, injectors leaking , cam timing .. may be not that but i would prefer the solinoid check first .

Thats my 2 pennys anyways.
 
Demort said:
I have a theory with some exhaust mods causeing problems while others dont seem to ..

My idear is that there was an existing problem which the mod has made more obvious .

Your fault codes could easily lead down 2 different pathes .. misfire being one route and too rich on B2 being another .

I have a hunch with no real basis but something i would like proved first on this is that the high lift solinoid bank 2 is ok .. either a replacement or just swop bank to bank as this will transfer the fault to the other side .

There is no actual Porsche fault code for this solinoid fault and different testers tend to give different codes .. mine at work always gives a lambda swoped code but on here ive never seen that although many people have proved the solinoids to be faulty.

Over rich .. hmm .. maf, injectors leaking , cam timing .. may be not that but i would prefer the solinoid check first .

Thats my 2 pennys anyways.

Thanks Dermot. Just to be clear, i had no problems when I first fitted the exhaust, only after fitting the dual cone air filters. That's not to say the combination of both have compounded to create the fault.

Previously I have had over rich faults on both banks, the misfire faults are new though.

The solenoids are something I had thought about, not sure what sort of fault they would create if they were playing up, but will try swapping them over anyway just to see whether I get a bank 1 over rich fault.
 
Rob ,
1/are you running oiled cone filters if so get some dry ones mate as it could be oil on the maff ,I had it when I used K&N filters as they use a heavier oil the bmc . pipercross will do you a special order dry filter but you may lose some of the induction roar but the air intake will be the same.
2/ did you reuse the lambdas when you fitted the 200 cell cats or did you buy new also when the engine was rebuild could the cats / lambda have taken a knock somewhere during the engine removal as the lambdas are super sensitive
3/ are you running rich because you need a remap or the new engine is still learning what set up to settle into.
4/ have you got gt3 throttle body / plenum on yours

:?: :?: :?:
 
Phil 997 said:
Rob ,
1/are you running oiled cone filters if so get some dry ones mate as it could be oil on the maff ,I had it when I used K&N filters as they use a heavier oil the bmc . pipercross will do you a special order dry filter but you may lose some of the induction roar but the air intake will be the same.
2/ did you reuse the lambdas when you fitted the 200 cell cats or did you buy new also when the engine was rebuild could the cats / lambda have taken a knock somewhere during the engine removal as the lambdas are super sensitive
3/ are you running rich because you need a remap or the new engine is still learning what set up to settle into.
4/ have you got gt3 throttle body / plenum on yours

:?: :?: :?:

Hi Phil

In answer to your :?: s

1. No, the cones are dry, so no chance of the MAF being fouled by oil.
2. I don't have 200 cell cats, still running the original ones, possible that they may have taken a knock during the rebuild but I expect Hartech knowing their stuff would take good care!
3. I think this is the case, I understand that it takes a while for the ECU to settle down and needs a few full power runs through the gears, can't do that until the engine is well run in, but I have dobe this previously! I will be getting a remap as soon as the engine is run in properly but want to make sure everything else is tickety boo beforehand!
4. No GT3 throttle body on mine.... yet!
 
DucatiRob said:
Phil 997 said:
Rob ,
1/are you running oiled cone filters if so get some dry ones mate as it could be oil on the maff ,I had it when I used K&N filters as they use a heavier oil the bmc . pipercross will do you a special order dry filter but you may lose some of the induction roar but the air intake will be the same.
2/ did you reuse the lambdas when you fitted the 200 cell cats or did you buy new also when the engine was rebuild could the cats / lambda have taken a knock somewhere during the engine removal as the lambdas are super sensitive
3/ are you running rich because you need a remap or the new engine is still learning what set up to settle into.
4/ have you got gt3 throttle body / plenum on yours

:?: :?: :?:

Hi Phil

In answer to your :?: s

1. No, the cones are dry, so no chance of the MAF being fouled by oil.
2. I don't have 200 cell cats, still running the original ones, possible that they may have taken a knock during the rebuild but I expect Hartech knowing their stuff would take good care!
3. I think this is the case, I understand that it takes a while for the ECU to settle down and needs a few full power runs through the gears, can't do that until the engine is well run in, but I have dobe this previously! I will be getting a remap as soon as the engine is run in properly but want to make sure everything else is tickety boo beforehand!
4. No GT3 throttle body on mine.... yet!


:grin: Rob not sure why I ended up with 3 :?: lol
well good that all those except part of Q3 can be discounted , you are right a few good hard full power runs are needed for the ecu to learn correctly but understand why that cant be done at the moment if your considering a GT3 tb/plen best fit that before the remap or agree a re-tweak price in advance with the mappers for when you do fit one. :thumb: :thumb:
 
Just for clarification, engine rebuilt, NEW plugs and Coilpacks fitted :?:

And just because they are New, they could be faulty straight out of the box, might be worth swapping them around to see if the error codes change too :thumb:

I get a CEL sometimes on my Boxster, lambda sensor not efficient, usually when I get held up during the warming up process and keep the revs too low :nooo:
 
kurlykris said:
Just for clarification, engine rebuilt, NEW plugs and Coilpacks fitted :?:

And just because they are New, they could be faulty straight out of the box, might be worth swapping them around to see if the error codes change too :thumb:

I get a CEL sometimes on my Boxster, lambda sensor not efficient, usually when I get held up during the warming up process and keep the revs too low :nooo:

Yes, I had new coil packs and plugs during the engine build.

I am trying to do longer journeys during the running in process, even taking the long route to work on the odd occasion I use it to commute. I am careful during warming up but making sure the engine has a decent work out without being silly.

I think I will take it for a good run over the weekend see if the problem comes back, if it does I will try swapping over the cam solenoids!
 
Demort said:
I have a hunch with no real basis but something i would like proved first on this is that the high lift solinoid bank 2 is ok .. either a replacement or just swop bank to bank as this will transfer the fault to the other side .

There is no actual Porsche fault code for this solinoid fault and different testers tend to give different codes .. mine at work always gives a lambda swoped code but on here ive never seen that although many people have proved the solinoids to be faulty.
.

I had the same symptoms you describe Rob, and I followed this advice from Demort at the time and swapped the solenoids between banks and the problem (fault codes) moved to the cylinders on the other bank, proving that was where the fault lay - I'd defiantly try what Demort is suggesting here first. :thumbs:
 
My guess rob is the cone air filter.

You're running the car in so, I presume at relatively low to medium rpm?

The engine is being starved of cold air to maximise fuel mixture burn imo. It's getting hot air from inside the engine bay instead.

I would bet that if you re installed the original air box with a bmc filter, your problem will be solved.

:thumb:
 
Alfaian said:
My guess rob is the cone air filter.

You're running the car in so, I presume at relatively low to medium rpm?

The engine is being starved of cold air to maximise fuel mixture burn imo. It's getting hot air from inside the engine bay instead.

I would bet that if you re installed the original air box with a bmc filter, your problem will be solved.

:thumb:

Ian, you are probably right, all the problems have been since I have fitted the twin cone filter, however it is not open to the engine bay. There is a carbon air box that mates with the air ducts on the turbo wing. If it is the twin cones, my assumption is that either the ECU cannot compensate for the extra airflow or there is some issue with the MAF!

However... today I used the car for my daily commute, fine on the way to work but on the way home I got the CEL again, engine was running fine and no misfiring or rough running! Checked for errors when I got home and got.

P2180 - System too rich off idle - Bank 2

No misfiring fault codes this time! Very odd!

Thinking your suggestion to put the original air box back on is a good idea, will have to put the original deck lid back on too, bit of a pain! At least I can then confirm or rule out if the twin cone intake is the source of the issues!
 
DucatiRob said:
Alfaian said:
My guess rob is the cone air filter.

You're running the car in so, I presume at relatively low to medium rpm?

The engine is being starved of cold air to maximise fuel mixture burn imo. It's getting hot air from inside the engine bay instead.

I would bet that if you re installed the original air box with a bmc filter, your problem will be solved.

:thumb:

Ian, you are probably right, all the problems have been since I have fitted the twin cone filter, however it is not open to the engine bay. There is a carbon air box that mates with the air ducts on the turbo wing. If it is the twin cones, my assumption is that either the ECU cannot compensate for the extra airflow or there is some issue with the MAF!

However... today I used the car for my daily commute, fine on the way to work but on the way home I got the CEL again, engine was running fine and no misfiring or rough running! Checked for errors when I got home and got.

P2180 - System too rich off idle - Bank 2

No misfiring fault codes this time! Very odd!

Thinking your suggestion to put the original air box back on is a good idea, will have to put the original deck lid back on too, bit of a pain! At least I can then confirm or rule out if the twin cone intake is the source of the issues!

Good idea rob :thumb:

I reckon the maf is all over the place with its readings and giving the engine too much fuel to compensate.

I'd say the plugs on the o/s bank will be sooted up if you were to take them out also.

Too much fuel can make the car misfire too.

That's my theory anyway :)
 
Alfaian said:
DucatiRob said:
Alfaian said:
My guess rob is the cone air filter.

You're running the car in so, I presume at relatively low to medium rpm?

The engine is being starved of cold air to maximise fuel mixture burn imo. It's getting hot air from inside the engine bay instead.

I would bet that if you re installed the original air box with a bmc filter, your problem will be solved.

:thumb:

Ian, you are probably right, all the problems have been since I have fitted the twin cone filter, however it is not open to the engine bay. There is a carbon air box that mates with the air ducts on the turbo wing. If it is the twin cones, my assumption is that either the ECU cannot compensate for the extra airflow or there is some issue with the MAF!

However... today I used the car for my daily commute, fine on the way to work but on the way home I got the CEL again, engine was running fine and no misfiring or rough running! Checked for errors when I got home and got.

P2180 - System too rich off idle - Bank 2

No misfiring fault codes this time! Very odd!

Thinking your suggestion to put the original air box back on is a good idea, will have to put the original deck lid back on too, bit of a pain! At least I can then confirm or rule out if the twin cone intake is the source of the issues!

Good idea rob :thumb:

I reckon the maf is all over the place with its readings and giving the engine too much fuel to compensate.

I'd say the plugs on the o/s bank will be sooted up if you were to take them out also.

Too much fuel can make the car misfire too.

That's my theory anyway :)

My thinking too Ian, I'm just confused over the fault being on Bank 2 only!! :dont know:
 

New Threads

Forum statistics

Threads
124,354
Messages
1,439,442
Members
48,708
Latest member
JLav211
Back
Top