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the better drive habits didnt last long.

running is going to be the same like before. almost.

 

i have always a one time wonder when i remove and reinstall the MAF the car is driving very good for some miles after this job.

 

what could cause this phenomenon? can i messure the voltage at the MAF connection? what reading i should see?

 

Thank you

 

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On 24 October 2016 at 5:15 PM, ekstroemtj said:

the better drive habits didnt last long.

running is going to be the same like before. almost.

 

i have always a one time wonder when i remove and reinstall the MAF the car is driving very good for some miles after this job.

 

what could cause this phenomenon? can i messure the voltage at the MAF connection? what reading i should see?

 

Thank you

 

This is the best article I've found so far on testing maf, I'm going to do it tomorrow if I get time. Using the Vagcom voltage of the maf is not entirely accurate maybe? Also will try a full acceleration log graph of the maf reading and see if it is looking correct. 

Will post my findings..........

http://easyautodiagnostics.com/vw/1.8L/maf-sensor-tests-1

Edited by lewisweller
usual

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I continue to work on finding the cause of my hesitation. Started to replace a lot of turbo related pressure pipes. 

On the firewall everything arround the change over valve. Everything arround the N75 valve arround the intake y pipe. Pipe which is going down to the wastegate. Just the passenger side. Driver side looks difficult. Car is running with every step a little bit better but its not perfect.

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this weekend i had to make a trip. almost 1400 km. most of them highway.

what i can say, the power is back after replacing all this turbo related pipes. the car is running not bad at higher speed. almost quiet.

but there is still this terrible hesitation during accelaration . 

before the trip i had a look under the car. i remember the phrase, if there is a problem go back to the place you was working before.

i remember when all this trouble started and i had to take out the air hose on the driver side, the pressure hose which is going out of the turbo direction intercooler was not very much fixed. that time i was thinking maybe it should be like this. now i know it isnt. when i crowl under the car this weekend i inspect this metal hose which is connected with the turbo charger. the gap between the 2 pipes is to big i believe. have a new seal. wanted to change but isnt easy to get access without removing lots of parts arround.

the 2 pipes are connected with a clip. the clip is open on one side. does anybody know in which way it has to be installed? 

 

 

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Can this gap / old seal at the pressure hose cause a bad running or i am mistake with my theory?

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4 hours ago, ekstroemtj said:

Can this gap / old seal at the pressure hose cause a bad running or i am mistake with my theory?

Fitted the pipe should be inside and almost flush against the turbo outlet opening, the clip just sits in a groove either side which stops the pipe from coming out, the oring inside around the pipe really does the job I'm of keeping the pipe snug and leak tight. Are you sure the oring is in there?  Sorry I can't find a picture of this installed. 

I changed the turbo to n75 valve reference boost pipe the other day, removed all the piping on the passenger side checked everything looking for some leak which could make this silly screech noise, found nothing, cleared codes and went for a drive, made no difference. The search continues. ....

IMG_20161112_113752.jpg

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I believe there is a o ring. Otherwise there would be metal to metal and this would feel different. I will find out. Here is a pic from a DIY which was made by a member here.

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11 hours ago, ekstroemtj said:

I believe there is a o ring. Otherwise there would be metal to metal and this would feel different. I will find out. Here is a pic from a DIY which was made by a member here.

IMG_4586.PNG

Hi Thomas, today I removed all the pipes on the drivers side, cleaned and inspected everything, I found the black pipe connector which screws to the turbo inlet was not tighten on the bottom screw, I can't say if it was leaking air in but I had hoped I may have found something. For the turbo outlet pipe I replaced the o-ring you pictured above, the pipe doesn't fit tight now ahhhhhhh and wobbles around :censored::censored:, why why why? 

I checked it 5 times to make sure all was in correctly clip is secure etc but it still wobbles around which doesn't seem right.

Any body experience this? Normal? Corrective action required? Will it leak? 

 

See pictures clip is on correctly, last picture I even installed it upside down to see if would stop wobbling around and be tight but no chance. 

I checked the turbo also no shaft play radial or axial and no visible damage to impellor. 

Checked dv all ok, (it was new few months ago but you never know)

Changed the DV vacuum pipe from the T to the DV, old pipe wasn't leaking but anyways whilst I'm there.  

 

On short drive home ran like crap really, I did reset the dtc so fuel trims would be zero'd and need relearning. Will see what its like in the morning have a long-ish run to the site early morning blast high speed. 

I notice if I do run long high speed the car will try to behave better than in traffic dogging it around, explain that someone pls?

 

Top it all off, Reversed in to parking bay and rear parking sensors not working double red lights means another sensor is dead again... already replaced one and it ain't cheap. Always something init! I just washed it before leaving warehouse so I bet water is inside one of em!

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Edited by lewisweller

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looks like you take apart half of the car.

the o ring and the wobble was my hope. now you are telling me its the same with you. looks like we have to continue to search.

 

how would it be possible to find out if the valve cover gasket is a reason? now i am really checking every place where my mechanic was working in.

 

anybody knows the torque numbers from the cover?

 

 

sad story, my parking assist also stop working yesterday. ;-(

 

 

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Even sadder story - I was just almost beaten by a 4 door KIA! A 2 lane getting on the highway contest, could barely keep a car length or two in front of him. Ready to sell it after that! But seriously, thanks for all the photos, I am now going to dig into mine and see if something is leaking, lowering my power output. Might relate to the transmission shifting problems too.

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What i feel is much more sad how the activity here in this forum is going to. If it was not a few people which have a wish to help there would be silence. 

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3 hours ago, ekstroemtj said:

What i feel is much more sad how the activity here in this forum is going to. If it was not a few people which have a wish to help there would be silence. 

Paid for the fuel filter and regulator today will pick it up on saturday and install it. 

Typical I've been keeping the fuel low and driving today with under 1/4 tank and the car runs better if not exactly correct so what does that tell? Primary and secondary pump running over comes a partially blocked filter or increases pressure to near correct value? Not sure but Gonna find out soon. 

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2 hours ago, lewisweller said:

Paid for the fuel filter and regulator today will pick it up on saturday and install it. 

Typical I've been keeping the fuel low and driving today with under 1/4 tank and the car runs better if not exactly correct so what does that tell? Primary and secondary pump running over comes a partially blocked filter or increases pressure to near correct value? Not sure but Gonna find out soon. 

 

 

I just read in a german forum about a guy who had similar problems. He is a bosch specialist. He was hunting for the problem and found. 

I will translate and send you. Maybe it will help you too

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10 hours ago, ekstroemtj said:

 

 

I just read in a german forum about a guy who had similar problems. He is a bosch specialist. He was hunting for the problem and found. 

I will translate and send you. Maybe it will help you too

I did the reset for throttle as per your instructions and before I also checked and Re-tightened the inlet manifold screws which I had a suspicion that they weren't tight enough when my apprentice Eng reinstalled the manifold after we remove the starter motor some weeks ago. 

The drive after the reset was great, felt much more responsive and smoother, the hesitation was still there on boost but much less stutter at higher rpms. Small Throttle inputs results in good power and torque the way I would expect a 500bhp v8 to perform, the boost builds and responds much faster and notably the transmission will not need to downshift! If engine is running bad it alway downshift when I don't really want it to and it's because the power and torque requested is not delivered by the engine and it downshifts to compensate, very annoying especially when you have passengers.

 

After 40km........

I went to put some more fuel in and DID NOT switch off engine since morning start, after I pull away from the petrol station I hear the screech noise again!!!!

I went to my clients house to collect some cash and found the pipe number 5 on the diagram is split in half, I used half roll of black pvc tape to fix and will buy a new one tomorrow. The noise is gone!! Result. 

 

So even though the engine runs better it still has something not quiet right and my hunch is fuel related. I tested, checked or replaced almost everything else within reason. 

I've already paid for the filter and regulator so whether it fixes the problem or is another "routine service maintenance" item for this ageing car (that's what I tell the wife hehe), I hope it's the final cure. 

 

Just a note the way the engine performs really affects the transmission shifting and smoothness. Torque peaks and incorrect rpm's upset the mechatronic in all vag/porsche applications, my Audi is the same the occasional hard shift when mid load acceleration but mostly silky smooth. 

 

IMG_20161118_122204.png

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I had similar oil residue under the engine too. My local dealer somehow ignored it when doing the last service. I noticed it when removing the lower engine cover to change the diff fluid. So I took to my Indy and they diagnosed both upper and lower oil pan gaskets.  Extended warranty covered it to the tune of $2500!!!!

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After some more driving today and sat at idle for at least 15-20 mins waiting for the wife, the engine definitely changed it's characteristics since driving this morning. 

So some thinking, 

1. Fuel heating and or pump getting hotter and lower output?

2. DME, throttle and or running adaptions changing to make poor running after some time especially after prolonged idling?

3. Closed loop o2 sensor cats problem? 

 

Anybody got some high level technical Bosch systems knowledge to share? 

Edited by lewisweller

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All I can add is mine is very sensitive to making running adaptations too; maybe try with and without PSM on? I found with it off it the adaptations are less, and it makes less “mistakes”. After idling for a while mine will definitely run poorly. Also agree that engine running condition has a significant effect on shifting.

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You guys have a lot of experience with the hoses up top, and I was hoping you could help – this is where my venture tube attaches to the Y pipe. Is it supposed to be on more? So is where the red arrow is supposed to be all the way up at the blue arrow? Or is there supposed to be some space? There is obviously some oil leaking there, and it looks a bit crooked.

DSC04053ss.jpg

 

Also, if you follow that tube back where it runs near the fuel rail it is rubbing on a bracket (at the arrow), which doesn’t look right either. Is yours like this? I can’t push it on any more without taking things apart, and I don’t want to break anything because it is really jammed in there. Thanks.

DSC04059s.jpg

 

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Yes this venturi tube should be better connected . Its a friggle thing.  Try to disconnect the y pipe to find out where this oil spray is coming from.

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Here you see the tube.  Going along the fuel rail to a connection into the intake manifold on the back of the engine. Take away the black engine cover on the firewall. Disconnect the passenger side air pump and you will have a very good access to this area

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This pic is from lewis. Showing the manifold from behind. No. 3 is the connection where your venturi tube has to go to. 

IMG_3636.PNG

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Well the New filter and regulator is installed. Job went smoothly enough I had very little fuel in the tank which was advised. 

 

The old filter I cut open as you can see in the picture and guess what it looks very clean to me, I would say it's not that old. The regulator looked older and had more dirt around it and the connectors were tight as F*** . 

Reconnected the battery and the Engine started on the button just fine as it always does. 

I was rushing to go home and watch the football, didn't clear codes just drove to fuel station, switched off engine and filled up and put some stp fuel system cleaner in as well. 

Pulled away hard from petrol station heard the screech again (didn't buy the pipe number 5 today, Porsche want $100 for a 5inch plastic pipe!  no chance, I will buy a hose and two clamps for $5 and make a better pipe than the brittle weak Porsche new one). 

So the verdict is inconclusive, I need to fix the pipe reset the dtc codes to clear clear fuel trims and do a throttle body alignment and and reset sequence and the lucky gypsy dance...........then go for some driving and see what's up. 

 

Gun to my head....... have I cured this problem? NO I don't think so but hoping I'm wrong. 

 

****Loren****** DME issues with these models any info pls? 

I'm considering trying to blag a friend to load me a trail REVO dme remap tune to see what it does with the running issues. 

 

IMG-20161119-WA049.jpg

IMG-20161119-WA051.jpg

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20 hours ago, Zakowsky said:

You guys have a lot of experience with the hoses up top, and I was hoping you could help – this is where my venture tube attaches to the Y pipe. Is it supposed to be on more? So is where the red arrow is supposed to be all the way up at the blue arrow? Or is there supposed to be some space? There is obviously some oil leaking there, and it looks a bit crooked.

DSC04053ss.jpg

 

Also, if you follow that tube back where it runs near the fuel rail it is rubbing on a bracket (at the arrow), which doesn’t look right either. Is yours like this? I can’t push it on any more without taking things apart, and I don’t want to break anything because it is really jammed in there. Thanks.

DSC04059s.jpg

 

The pipe elbow arrow red is a push fit type and mine does NOT go all the way up, the Y pipes spigot arrow blue is LONGER than the the pipe elbow push fitting so this looks correct to me. But it's leaking for sure. 

The (part no 25 on diagram) pipe running horizontal in front of it is not supposed to be there, it supposed to be behind the elbow push fit pipe! There is a plastic tab moulded into the bottom of the Y pipe which the horizontal pipe sits against and stops it rubbing against the water pump pulley. I expect that the horizontal pipe is pushing on the push fit elbow and making it leak or has damaged the push fitting already. 

 

Take the Y pipe off rearrange the pipes clean and refit. If after some km it's dirty and oily again bingo it's leaking 100%. 

Also whilst running after re-assembly spray some carb cleaner on it and listen for the rpm rising. 

Usually it will leak under boost and push out oily air then the oily air deposits collect dust and make the mess you see now. 

 

IMG_20161120_070623.png

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