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Lou P.
Lou P., ASE Certified Technician
Category: Porsche
Satisfied Customers: 4965
Experience:  I Have knowledge in almost all car lines and can help with general questions and more!!!!!
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I have an 01 porsche boxster S 3.2 motor. I just replaced

Customer Question

I have an 01 porsche boxster S 3.2 motor. I just replaced the motor with a 18k donner car. My eng had the notorious IMS bearing go out at 80k. I had all the updates done to the new eng. New motor runs perfectly. My problem is the check eng light comes on with codes for o2 sensors aging. I have replaced all sensors. Light still comes on with same code. Took it to a Porsche certified mech. They spent 3days trying to figure it out. They would clear codes and still shows same codes. Also said when they heel toed the car, it would throw the codes. They finally changed the MAF sensor which gave it green ready to go.. sent me to the smog to smog it but told me not to heal toe it.. They were not sure it would last.. I same day, got it smogged, but after 150 miles the light came on again with same codes..(aging o2 sensor ahead of cat.??. I have a year to figure this out but it bugs me... Also a Note.. The motor came from a tiptronic automatic trans and my trans is a 6 speed.. would the potentiometer be different? I also bought the accelerator pedal and potentiometer out of the 18k doner car just incase that might solve the heel toe effect.?? I hope you can answer or head me in the right direction.. Sincerely, Brian
Submitted: 1 year ago.
Category: Porsche
Expert:  Lou P. replied 1 year ago.

Hello Brian, the first thing i would ask it, did you make sure the wiring is not pinched somewhere? if it is only one sensor then i would inspect the wiring, if it was software or something you would have issues with both sides i would imagine. did you swap over the wire harness or did it come with the new engine?

Customer: replied 1 year ago.
After changing all the 02 sensors, I drove it for 250 some miles with no check eng light showing. But it was showing that the ECU was still trying to make up it's mind to green light it. So I took it to Hergesheimer to figure it all out. Three days later, they said it throws codes when heel toeing it. They finally changed out the maf sensor and it green lighted.. sent me immediately to get it smogged. I smogged it and drove it for 148 miles and the check engine light came on again for " aging o2 sensor up river of caty. I Cleaned the MAF and erased codes. Drove it to work today.. no check eng light today yet. But I will have to drive it so many miles to reset ECU to green ( I hope)
Hergesheimer check for pinched harness wires ( none found) ..
Since it seems to come on when heal toeing, Maybe the Potentiometer is different from a tiptronic to a Manual6 speed?
The Harness did not come with the new motor but the shop said it shouldn't matter and used my harness.. ?
Codes started with Fuel cap code, possible pin leak , then went to the O2 sensors, left side and moved to right side.. I replaced fuel cap, all o2 sensors, MAF sensor, Maybe Software???
Customer: replied 1 year ago.
Does the brake light sensor and the potentiometer read each other?? I do not have the option of PSM or whatever that's called.. But maybe the donor car had it.. So when you heal toe it...it can't read the brake sensor to the potentiometer?? Therefor confusing the computer and throwing any codes..?? Sound reasonable?? I'm Guessing ..
Customer: replied 1 year ago.
Are you there ??
Expert:  Lou P. replied 1 year ago.

I am here, sorry, trying to go over your story and see what may be happening

Customer: replied 1 year ago.
no worries.. Take your time and ask me any thing.. This is my first time doing this so wasn't sure how it works,,.. Tks Brian
Expert:  Lou P. replied 1 year ago.

OK, so you did have aging codes for both front o2 sensors?

Expert:  Lou P. replied 1 year ago.

and what was the PXXXX codes?

Expert:  Lou P. replied 1 year ago.

and this works no different then texting well chat until we come to a conclusion, you rate me for service and you choose when to end the chat :)

Customer: replied 1 year ago.
Got it,,
I cant remember all the codes .. I do have them written down at home.. The last was (i think)p0126
p1128 p1124 ..
I changed all sensor.. all Bosch replacement o2 sensors
Customer: replied 1 year ago.
I do know that when I looked them up,, the last was ageing of o2 sensor passenger side ahead of Catalyst.
Customer: replied 1 year ago.
I was also worried about the O2 sensors downstream as I had to splice to reach. I crimped and not soldered because i didn't want to change any Ohms (sp) ... But no codes for the downstream o2's ever came up..
Customer: replied 1 year ago.
only the upstream ever coded..
Expert:  Lou P. replied 1 year ago.

OK I gotcha, did they ever reset adaptations? reset the the fuel trim learning?

Expert:  Lou P. replied 1 year ago.

so ill need to see the exact codes you had so if you cant get them till later that is fine i will get emails when you reply .

Customer: replied 1 year ago.
I would think that Hergesheimer did.. I have their receipt at home and i think it reads (reset all codes) .. They have the same code reading instrument as the Porsche dealer to reset on the spot.
Customer: replied 1 year ago.
Do you want me to scan and email you a copy of their invoice?
Expert:  Lou P. replied 1 year ago.

ok, well resetting codes and resetting fuel trims is different, also hopefully their scanner can read fuel trims as that reading will help as well. do you know what i mean by fuel trim? also vacuums leaks can cause this and a faulty air mass sensor as well. and yes any info you can provide me will help us, this is a somewhat common and not common issue in the same since you have the variables of the engine swap. so this may take a little bit.

Customer: replied 1 year ago.
I just use a OBD device. to read and erase etc codes.. theirs has all the exact porsche codes mine does not..
Customer: replied 1 year ago.
Do i just keep talking to you here later?
Customer: replied 1 year ago.
Does this turn into email for you.?
Expert:  Lou P. replied 1 year ago.

Well no its a chat , but i also get emails so in case i am away from my computer

Customer: replied 1 year ago.
Ok in that case, I can call Hergesheimer and see what codes they pulled .. as well as what's on my invoice at home..
I will re-enter this chat room after 4:30pm California time.
And hopefully be able to type all the info to you..
Is that good for you ?
Thanks for all your help too..
Maybe we can figure out this problem..
Expert:  Lou P. replied 1 year ago.

THAT works man, im here like all the time :)

Customer: replied 1 year ago.
Good morning Lou,
Found all the codes as well as explanations of work done after Replacement Engine. As follows;These are the codes;
P1275
P1276
P0133
P1219
P0153Explanations;Connect Porsche Systems Tester to vehicle and run engine diagnostics. Note faults and assess for course of correction. Readiness codes are not set. Road test to set flags,check diagnostics.Vehicle arrived with:
Catalytic converter efficiency, both banks not passed.
Oxygen sensing delay, bank 1 not passed.
No fault codes stored.Road tested, Fault code P0133 and P1219 faulted
P0133, Aging of oxygen sensor ahead of catalytic converter, cylinders 1-3, below lower limit.
P1249 Accelerator pedal potentiometer, signal implausible.Tested oxygen sensors, switched oxygen sensor to different bans. Fault codes persisted.
Additional code P0153
P0153 Aging of oxygen sensor ahead of catalytic converter ( cylinders 1-4, interruption signal.)Inspected fuel trim and mass air flow rates. Found Mass air flow sensor faulty. After replacement of MAF, road tested and set readiness monitors. No faults found after road test.No DME fault codes stored at this time.This was the last time in the shop.. Around 143 miles since then and check eng light came on with code P1276 ..
Hope this helps you??
Brian
Expert:  Lou P. replied 1 year ago.

Good morning as well, i will go over and get back with you, thanks!

Customer: replied 1 year ago.
Great .. please take your time..
Just food for thought???
I went through the previous owners receipts last night and found that he had ECU work done. ECU Performance Programming. Cost him $840.00 so don't know if a chip was installed or just tuned ??
But that may influence a new motor exchange ?? I'm pulling at straws,..
Talk later..
Expert:  Lou P. replied 1 year ago.

AH!, that may be the money shot, we will see. good catch!

Customer: replied 1 year ago.
Good morning Lou,
Just wondering if you had found any leads yet.??
BC
Expert:  Lou P. replied 1 year ago.

I was trying to find more info on the ecu programming and what may have been influenced, they did make some good notes on the repairs and diagnostic steps (the repair shop) , the fact that they said they swapped sensors from bank to bank and the code persisted tells me that its wiring or ecm related for there is a issue with the fuel trims on that bank as far as a internal wear issue or fuel issue or air issue. but i am surprised it is setting a again code and not a lean or rich code. so bear with me as i try to find possibilities.

Customer: replied 1 year ago.
You got it Lou.. Thanks....BC
Expert:  Lou P. replied 1 year ago.

no problem,. ill be back

Expert:  Lou P. replied 1 year ago.

Sorry I lost your chat. Finally found it. So where did you get the "new"oxygen sensors from ?

Customer: replied 1 year ago.
No worries...
They are Bosch OEM .. Had them ohm tested.. all are good to go..
Expert:  Lou P. replied 1 year ago.

ok, cause there is a issue with some aftermarket sensors, they cause false o2 readings. BUT since the sensors were swapped side to side that should rule them out.

Customer: replied 1 year ago.
Exactly.. Swapping should have pinpointed a bad sensor. Bosch is ( I believe, ) the OEM replacement O2 sensor. They certainly cost like it..
Expert:  Lou P. replied 1 year ago.

LOL, for real, ok did your new engine come with the ecm as well? do you have it?

Expert:  Lou P. replied 1 year ago.

CHECK this bulletin out. it is very interesting cause it also has all of your codes. you may want to show this to the shop.

Customer: replied 1 year ago.
It came with all that was anchored to the motor, ae: A\C Comp, Alt, Intake and throttle body Injectors.Etc... I should say it "only" didn't come with the starter, Someone grabbed it off...
All else was on the motor.. Anything else was not included such as ecu's etc
Expert:  Lou P. replied 1 year ago.

ok i gotcha. check out that bulletin i just sent, we crossed paths

Expert:  Lou P. replied 1 year ago.

ignore this message it was accident

Customer: replied 1 year ago.
I just got Three replies from you ,, all say "ignore this mess" Di I ignore all three ..lol
Customer: replied 1 year ago.
I just read the bulletin.. I Have a Aftermarket induction airbox. K&N filter.. (of which I have cleaned and run almost dry due to experiences with oil build up on the Mass Air Sensor in other cars.) I also dry wash (spray on wipe off ) the car 95% of the time as it is always garaged. Very rare that water gets into the intake.
Expert:  Lou P. replied 1 year ago.

ok, you know what, try a normal air filter......... why it would only affect one bank i cannot say, but a high flow air filter is actually bad for the german cars as they are smarter than the average cars, on a few 6.3 amg mercedes i found that a high flow air filter caused the engine to go into limp mode as the air flow is higher than what the computer logistics is looking for.

Customer: replied 1 year ago.
I never liked these filters, But the car came with it.. I've since stopped using K&N on all our cars.. Less chance of dirty MAS. I'll have to find a used airbox..
Expert:  Lou P. replied 1 year ago.

OK, i dont want to seem like im pulling at straws but the more info you give me about the scenario the better i can form a opinion on what is happening.

Customer: replied 1 year ago.
This email is acting up.. I sent you a history on the car and i don't see it here.. but two of your pulling at straws emails came through..
The car ran and smogged fine with all the pretty much everything on it. The only change is the motor.
I did the IMS, Clutch, TB,& PP, and a rear seal. etc.
All else was the same as before.. Now you can ad a MAS and O2 sensors.
I just bought a OEM Airbox, so I will return it to original Airbox when I get it. Unload the K&N.
Expert:  Lou P. replied 1 year ago.

ok, let me know, if not there is not much i can do without being the one in front of the scan tool watching the values. so let me know how it goes, if it doesnt take care of the issue i suggest a porsche dealer, i know you said porsche certified mechanic but certifications mean nothing in the auto world, you just need to take a open book test to be certified, but the dealer guys are the best ones to look at this scenario. hope something i sent you has helped. so let me know how it goes .

Expert:  Lou P. replied 1 year ago.

Please take a second and click the box and rate my service GOOD OR EXCELLENT SERVICE if you feel I have been helpful and please request me in the future. If you feel I have not been helpful please DO NOT RATE BAD OR POOR AND WASTE YOUR MONEY , I will opt out to see if another expert can provide more or better assistance so you're not wasting your money!!. Thanks for choosing just answer. Lou. also , if you feel i deserve one , BONUSES are GREATLY APPRECIATED ! 😉

Expert:  Lou P. replied 1 year ago.

o

Expert:  Lou P. replied 1 year ago.

I have taken my time to answer your question the best i could and i will continue to help if you need follow up information , all i ask is that you PLEASE take a second to rate my service so i may recieve my credit for assisting you. Thank you.