[Ecca]

Hi Guys. I have a 2008 R50. I have only recently purchased the car and it was fantastic until now. Engine is running on 5 cylinders, RH bank only. It happened on startup. Park the car it was fine, tried to use the car some weeks later and the problem occurred. My first thought was an air flow meter. Checked it out with my multi meter and all is good. I was a bit lost then so I Purchased the vag-com system from Rosstech. All checks out good on Vag-com. I have a bass speaker out and a steering angle issue. When I do a diagnosis with the engine running I only get random misfire error. I have had a look at the voltages with the engine running and I think all is good. Now I am thinking a wiring fault. Maybe the power feed to the injectors on one bank?? I am hoping there is a fuse or something for that side of the engine.
Any ideas anyone? Does anyone have a wiring diagram for the engine.

Thanks for the help

 

[Ecca]

Are you sure you scanned both banks? They are completely seperate on the VCDS scan as there are 2 ECUs. John

Can you explain address 11 to me? I did a a auto scan with the VCDS. I will get a scan and post it. Yes I live on a farm and my wifes car some years back had rodent damage. I cannot see any damage/evidence. Is there a place I should look.

 

[Ecca]

Hi John. Thanks for your help with this problem. I am still learning the VCDS so any advice is appreciated. I did a auto scan that I thought checked everything. When I looked at the voltages I could see 2 air flow voltages, 2 boost pressures etc. I think I am talking to both ECUs.
Let me explain the how I think it is on 1 bank. While running if I stick my hand under the car and touch the exhaust the RH side is hot and the LH is cold. If I squash the intake rubber hose, both sides will suck in. So both banks are turning pistons and camshafts. Engine sounds laboring while running. If you use any throttle your can hear the turbo spooling up. Watching this on the VCDS you can see the MAP pressure rising on one bank more than the other. The above observation has made me think it is only fueling one bank. Thinking more about the problem I think it has done a similar thing before. I noticed poor running once before. I shut down and re started and all was good. Your thoughts will be much appreciated.
Regards Eric

 

[Ecca]

I have attached the scan (I hope) I know this is not the correct section but it is relating to this thread) This scan was done with the car running. If I clear the dtc there is no fault seen in the vcds until the engine runs. Then all I can see is a misfire. Any help appreciated.

 

[Ecca]

Sorry try this one.

 

[Ecca]

How do you scan engine 2?? I cannot see this feature in the Ross tech Vcds. I thought an auto scan did the lot??

 

[Ecca]

Thanks Drag
Issue is the LH , passenger side of the engine. I cannot be sure all are not firing. In my searching I have see there are pumps on the end of each head. I am thinking more electrical as the first time it did a similar thing it came good after a restart. I would like to check the power feed to the injectors. Not sure how it runs on the treg. Most cars have a constant power feed to the injectors and the ECU grounds the injectors to fire them. Is the treg the same? Do you know where the power feed comes from? Any fuses? Do you have wiring info for what I am talking of? Another reason I am thinking a short circuit as it appears the battery is going flat. I am in a process of measuring the voltage drop. Not sure if it me playing around with the car or there is a problem. I will recheck the voltage in the morning.
Is there any way of seeing the injector duty cycle while its running via the vag com?
I have seen the output test on the vag com. I was little scared in this section so I did not look too hard but can I test the injectors and pulse them.
Thank you very much for your advice.

 

[Ecca]

Hi Ian. thanks for the link I will check it out. Engine runs OK considering. Labouring but smooth.

 

[Ecca]

Hi Drag. I am struggling with the attachment on the injectors. I opened them in notepad and they do not mean much to me? How do I use this info to test the injectors.

 

[Ecca]

I have the wiper cover off. The RH side (sitting in car) there is a ECU laying parallel with the road. I think the second ECU is close to the center of the car laying vertical. I have seen the 2 plugs on the RH ecu. center ecu still has its cover on it. Which ECU does what? You say unplug the small plug. Has the small plug only the injectors? Have you done this yourself? I do not want to damage anything. Unplugging ECU while running sounds like it may cause other issues.

 

[Ecca]

Hi Guys
I thought I would update you with my progress. After checked all the injector electrics, no fault found. In the course of running the engine for checking , it was running better. So much so I drove it with the Vag-com in scan mod. Results were lean on the LH bank and struggling to make the correct boost pressure on that bank. If I drove it hard it would error and drop into limp mod because it could not reach the target boost. Played some more the next day and running even better. Cannot get it to error but can still see slightly lean mixture on the LH bank. Mixtures starts off OK and the harder it revs the leaner it gets. Changes gear and mixture is OK and then leans off again as the revs rise. Can not to too much of this within the law and not crashing.
My guess is the pressure pump for this bank on the head is faulty. I cannot explain why it runs OK now. If the Vag-com was not connected you would think the car is fine now. I am thinking the pressure relief valve in the pump is faulty. Initially jammed open so the LH bank had very low fuel pressure so began the 5 cyl post. Some how it is working better now so the fuel pressure is closer to right. I think still not perfect as the mixture leans off. Anyone see these symptoms??

I want to check the fuel pressure but this I can see is very difficult. Engine out time I think. Not happy

Need to thank Drag for all his help. I would be in more trouble if it was not for his guidance.

 

[Ecca]

I am wondering why your changed both the pumps if they were OK. High mileage? Maybe you had the engine out for other reasons and decided on some preventive maintenance. I am curious.
I think you right about the freight cost. I think if I change them I will go with new. Still considering if a rebuilding the pumps will be acceptable to me. I will decide when I have one apart.

If the engine does comes out what should I do at that time. I am thinking of the following but open to suggestions. I love the car and plan on keeping it for many years. (mileage 107,000KM)
Cylinder head fuel pumps. replace/rebuild
Fit "tee"pieces in lines from pumps to rails to allow for pressure testing in the future.
Test all injectors and replace /repair if required
Repair cracks in exhaust manifolds. ( guessing it has some )
Check turbos for end float / damage.
Clean inside of inlet manifolds
Remove EGR system
Clean DPF filters

 

[Ecca]

Hi Guys. I thought I would update you with my progress. Engine is out. Problem is with the mechanical fuel pump. If you look carefully at the picture of the pump. (if you can see past all the rubbish in it) The top spring of the vane has broken and turned sideways. I think this piece of spring would have jammed the relief valve causing the only half the engine to run. Lots of damage in the pump where the piece of spring went through. Check the pictures.

 

[Ecca]

Hi Guys. Thanks for the comments on my shed. I took the engine out myself. Scary , but not as bad as you think. After I purchased the car I became aware of a exhaust leak. On investigation I discovered the exhaust manifold crack so the engine out was happening at some stage anyway. Pump problem just made it happen now.
I have attached some pics of the exhaust manifold. look carefully at the base and you can see the crack. Front leg has a small crack also. Not a great design how the material is pushed into the runner shape. Very thin in this area, hence the cracks. I am going to repair and upgrade. I will post some pics of the results.

 

[Ecca]

Hi Guys
I have had a go at repairing the exhaust manifold. I TIG welded around each leg a few times to build the weld to the factory MIG welded join. This also made the radius where they crack much thicker. I will be very surprised if they ever crack again. Manifold did pull during the welding process. I had to mill .4mm to square up all the legs.

Photos show a repaired leg and factory leg. Milling process and the finished manifold

I am going to do the other side as well. It has no cracks now but after seeing the design it will just be a matter of time. I will do my mods now while the engine is out.

 

[Ecca]

Latest update.
After my exhaust manifold repair "Drag" suggested I check the camshafts as these have been know to wear. Well my camshafts were damaged. Not happy at 105000 KM. Decided not to fit the same cams because I did not want the same problem again!! Fitted a set of Colt stage 2 cams. There is a long story about the difference in VW to Colt cams. Send me a PM if you are going down this road. I have come this far in the upgrade so I made a engine breather tank to stop the blow by entering the engine. Best spot to mount the tank was the EGR cooler position. All looks factory and the engine cover fits over the top. Acid cleaned the intake manifolds and even drilled for a boost pressure tapping. I could not stop there so I fabricated new exhaust pipes from the turbo to the back of the the transmission. Pipe at the turbo was tricky with the flange. Engine ready to refit. Booked for a dyno tune in a few weeks.

 

[Ecca]

Hi Rob. Thanks for your kind words. Pump failure did not cause the camshaft failure. About the only thing that might link them would be a poor service history. These cars and a few other VW engines have the cam problem. Design is not great and if the service is not 100% I think the problem is magnified.
My job is with race cars so over the years I have picked up some skills. It was/is a daunting project but I love the car and now I think it will be a first class R50.

 

[Ecca]

Hi Guys
My R50 is going again and the dyno tune has been done. Very happy to say the least. Once I had the car running I had an EGR and DPF fault codes. It was expected as these have been removed. Car was drive able (not in limp) but the warning alarm was annoying to say the least. Exhaust note was good. Surprisingly not very loud. When you stand behind the car you can hear the turbos wine. Sounds very cool. No drone inside the car and you would not know the exhaust has been changed.
The guys that tuned the car had done an R50 some months earlier. I had to use this car as my base. On their 4WD chassis dyno a R50 makes 182wKW. My R50 with Camshafts, exhaust mods, engine breather mods and a Retune made 238wKW. A 56KW improvement. This is over 30% if my maths is correct. This was a "soft" tune as the car is a tow vehicle. They tell me there is more available but the exhaust temps become high. OK for street use but not for towing. Car feels really good to drive. Much better than original although I had only driven the car a few 1000 KM before the problems occurred. It also had damaged cams so this may have degraded the original car to me. I loved the car before, but now!! A few low KM oil changes to flush the cam material out and hopefully happy motoring in the future.
I would like to thank all who helped and followed the post. A very special thanks to "Dragline1570" Without his help I could not have done the project.