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Posted (edited)

No only the pads or ramps on Bank 1. Solenoid and pads on Bank 2. When I brought it to indie before the DME fix he said the the actuator on 2 was not moving. Said Bank 1 had -19 Degree timing and Bank 2 had 0. Not sure if that helps. V

Edited by vza

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19 minutes ago, vza said:

No only the pads or ramps on Bank 1. Solenoid and pads on Bank 2. When I brought it to indie he said the the actuator on 2 was not moving. Said Bank 1 had -19 Degree timing and Bank 2 had 0. Not sure if that helps. V

 

He said the actuator on 2 was not moving probably because when he tried to activate the bank2 variocam by Durametric or Porsche scanner, the engine note stayed the same. We already knew that's because the DME bank2 transistor was bad.

 

If he meant "-19 degrees Cam deviation for bank 1", then you found your problem. The spec is 0 degree +/- 6 degrees for cam deviation. Anything not in spec could generate misfires. That's why I want to see the "Cam deviation" reading from Durametric to see if they are in spec or not.

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Yes, I agree Bank 2 didn't activate cause of the failed but now fixed DME. Would he(indie) have them stored or should I confirm he said -19 degrees or you would want to see what it's saying now(a new scan), maybe time for a durametric, I called today to see if they had a refurbished one, they occasionally get one in.

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The best is to get a fresh reading because that -19 reading may have been measured BEFORE the bank 1 cam pads were replaced. New pads/actuators/timing will give new reading. We really need to know the current cam deviation readings for both banks to move forward.

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Posted (edited)

If you believe your coils are healthy, you could swap the coils between banks in the meantime.

Edited by Ahsai

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I'll swap the coils. Maybe its only fatigued coils!! The current reading I have(-19 degree business) was with all the work complete with the exception of the DME fix. v

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5 minutes ago, vza said:

I'll swap the coils. Maybe its only fatigued coils!! The current reading I have(-19 degree business) was with all the work complete with the exception of the DME fix. v

 

In that case, that needs to be fixed also because it will also trip a code/ CEL. It is not currently because it's likely suppressed by misfire codes.

So your mechanic just handed the car back to you with the -19 degrees cam deviation without mentioning the potential issues?

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Posted (edited)

Yeah pretty much....went to him once....said Bank 1 was compensating for no actuator in Bank 2, advised me to replace the bank 2 actuator and if that didn't work the engine would need a tear down to check for bent valves!! I've been to 2 indies and they both didn't want to deal .....said it would be very expensive going forward but no one really gave me a diagnosis.Wasn't very helpful. V

Edited by vza

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Quick question: I assume I should clear the CEL's after doing the coil swap? Thanks V

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47 minutes ago, vza said:

Quick question: I assume I should clear the CEL's after doing the coil swap? Thanks V

Yes, that would be the best.

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OK, Swapped sides with coils and cleared CEL. Got another CEL half hr into the drive. The same misfires on Cylinders 1-2-3. So I guess its not the coils. Part #'s on the all the coils were the same with the exception of THA3 (on 3 of them) and HEB3 (on the other 3) not sure if thats relevant. Codes are as follows:

 

P0300 Misfire damage to TWC               Pending Codes:   P1313   All Misfires 1-2-3 

P0301 Misfire 1 Cat damage                                                  P1314

P0302 Misfire 2 "        "                                                             P1315

P0303 Misfire 3 "        "                                                             P1319  Misfire emission relevant

 

Any ideas: vacum leak/knock sensor/ flywheel or cam sensor??

Thanks...

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Posted (edited)

None of the above. As discussed before the -19 degrees cam deviation in bank 1 is the likely culprit of the misfires. The spec is 0 degree +/- 6 degrees so -19 is way out of spec.

Edited by Ahsai

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Either will be able to re-time bank 1 but before any work the cam deviation should be read to confirm that is indeed the proble first.  Did you mention an indy replaced the bank 1 variocam pads? If so, they should redo it under warranty.

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No, I did all the work myself. I'm wondering if its the wear pads between cams or the tensioners? v

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In that case, why not get a Durametric first and if it's truly a -19 degrees cam deviation, you can consider redoing it again by yourself as long as you have the proper special tools. If not, you can use it to further diagnose your problems. You can read the misfires of individual cylinders in real-time. Your bank2 variocam would have been diagnosed much quicker if you had Durametric.

 

You can also use the Durametric to verify the timing is done properly. Also, when you don't need it anymore, you can sell it and get back at least 50% (2 free VIN slots out of 3) of what you paid.

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Posted (edited)

OK...ordered my durametric....coming next week!! 

From what I can tell I will be able to see a graph and value for Banks 1 and 2 cam deviation. Any other things I should be looking for?? V

Edited by vza

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Yes, you can monitor misfires on each cylinder in real-time. Also read FRA and RKAT (fuel trims) on both banks.

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VZA - There is a separate thread (that I can't find- sorry) that has the "Actual Values" you need to see when you use Durametric.

Make sure your new Durametric has all the updates before you use it.

When you use Durametric to activate the solenoid , you can definitely hear/feel the subtle change in the engine.

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Posted (edited)

Hi all, Well got my Durametric on today...Seems that I have -15 degrees deviation on Bank 1.Bank 2 reads 0 deviation. I think my fuel trims look ok (just a guess,didn't find an option for RKAT) somehow they didn't move at all when at 2500 rpm's. I activated both Actuators and heard a engine note change so I believe they're both working.I disabled my injectors one at a time and noticed there was more of a change in engine note with 4-5 and 6,not much change when 1-2 and 3 were disabled. How do I monitor misfires in real time?? Any thoughts would be appreciated. Thanks V 

Dura2.jpg

Edited by vza

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Excellent. Bank 1 cam deviation is way out of spec, which is 0.0 +/- 6.0 degrees and you have -15 degrees. I believe that's the source of your bank 1 random misfires. The solution is to re-time bank 1 and replace the cam pads if they are original/worn out.

 

Both banks are running RICH under load based on the FRA readings. FRA in bank 1 is a bit low at 0.87, which means the DME is reducing the fuel by 13%. Bank 2 fuel is reduced by 7%, not too bad. The bank 1 FRA could be a consequence of the excessive cam deviation.

 

TRA1 and TRA2 numbers are in % and they look great. So it seems no intake air leak.

 

For monitoring misfires, go to DME actual values and select "Misfire cylinder #1", "Misfire cylinder #2", etc.

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Ok...retime bank1.Are the trims supposed to move when the engine is revved...nothing changed.What cam pads are you referring to? The 2 small pads on the actuator? They were done already. Thanks for getting back.v

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Posted (edited)

The TRA should vary a bit when you rev the engine. The FRA is more long term adjustment when engine is under load so just revving the engine a bit won't make FRA move. You have to drive the car but even then you may only see small changes day to day.

 

Yes, the small actuator pads. When you retime it, make sure the chain marked links are at the correct places on the cam sprockets.

Edited by Ahsai

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Posted (edited)

OK ...well the chain marked links I have something to say about that. When I timed the banks after I had the cams out to replace 1 solenoid and all the pads this is what happened. I recall it happening on both banks. Had the cams on my bench, lined up the dimples with the colored links, got the actuator back in between cams reinstalled cams with colored links still lined up(was very meticulous about this) set timing and torqued up the sprocket nuts...colored links were still good. Rotated the engine few times...colored links moved but the timing still appeared good. TDC, notch on intake and exhaust cam stilled lined up. To be safe I tore it down again....ugh. Repeated the entire procedure but marked sprocket and links with nail polish so I could eyeball it from any angle. Re-installed everything,rotated the engine few times and it happen AGAIN, it all appeared to line up but the colored links moved again. I was able to count the links between the dimples and it was the same amount as between the colored links(I believe it was 6 links don't recall) I posted what happened here or rennlist and got a response that this was normal...so I went with it. Started the car and got a nasty knock in bank 2 (which is what I just described) ran it for a while and revved engine some cause some said the tappets weren't pumped up. Turns out I lost timing on bank 2 (exhaust cam was no longer lined up) I took the scavenge pump off loosened bolts on sprocket nudged it and lined it up, checked the number of links between dimples(colored ones were still off) closed everything up....knock was gone. I could never figure how the colored links could move and still have the same amount of links line up with the dimples. I know this a long post but I really hope that I'm explaining it so you can understand. The colored links moved on Bank 1 as well if I recall...I wound up counting them as well. I didn't use the Porsche chain tensioner tool that supposed to put pre-tension on the chain. Just used the tensioner.Thanks for reading thru all of this. v

Edited by vza

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