Forum HotHatches Information

[SpdR]

1. Diverter valve failure

Background:
The stock diverter valve (dv) is prone to failure, whether chipped or stock. The diaphragm is prone to tearing (the orange shown in the pic of the stock dv (in the middle) below-may be a different color depending on the version of dv you have.)
(IMG:http://img.photobucket.com/albums/v406/dpham00/forgedvinstall1.jpg)
Symptoms:
-A failing diverter valve will generally lose boost.
-The boost can be checked either via a boost gauge, or the vag-com (mb 115). You will see a huge drop in boost when the dv goes bad.
-Pin-hole DV failures usually allow boost to spike, but will then suddenly vent boost.
Tearing in the DV usually only allows 6-7 PSI. Boost will not spike.
-You may see 000665 - Boost Pressure Regulation: Control Range Not Reached
p0299 - 002 - Lower Limit Exceeded - Intermittent
-Alternatively, you can remove the dv, and inspect the diaphragm for tears. It is held onto the compressor housing by three bolts:

(IMG:http://img.photobucket.com/albums/v406/dpham00/turbo.jpg)

Solution:
-You can replace it with the stock dv, vw #06F 145 710 C. This is the latest dv as of this post, however, many people have also seen failures with the “C” dv. VW is also supposedly coming out with a “G” dv, part # 06F-145-710-G, though it is not officially released as of this post.
-You can upgrade to the Forge DV #fmfsitv. Pics of the Forge DV are shown above.

2. Positive Crankcase Ventilation failure

Background:
The positive crankcase ventilation is supposed to let gases get sucked from the crankcase to the intake manifold when under vacuum. The problem is, when the pcv system fails, and allows positive pressure (boost) to go from the intake manifold back into the crankcase.
(IMG:http://img.photobucket.com/albums/v406/dpham00/pcv.jpg)

The latest PCV is the “G” version. To see which version you have, take a small mirror, and stick it under the pcv valve. The last letter identifies the revision (“E” is shown below). The part # is under the round section:

(IMG:http://img.photobucket.com/albums/v406/dpham00/pcv1.jpg)

Symptoms:
-Typically you will see a slight drop in boost pressure. When my pcv failed, I saw a 2 psi drop across the board.
-Some oil will be pushed out through the oil filler cap, and onto the valve cover, and may possibly go towards the coil packs. There may also be some oil on the bottom side of the engine cover, where the oil filler cap is.
-There might be a slight decrease in MPG.
-Rear PCV failure usually results in oil accumulation around the DV, and will produce a little blue oil smoke at WOT applications.

Solution:
-There is the Digitalhippie fix which puts a check valve into the line from the crankcase to the intake manifold. For those who want a spare of the hose where the check valve is installed, the part number is 06F 103 221 F. You can read more about it here: http://www.golfmkv.com/forums/...=8952
-You can also upgrade to the latest PCV “G” valve. There have been very few failures reported with this PCV. Please verify the PCV you have before upgrading.
Part numbers for this upgrade:
PCV valve cover assembly: 06F 129 101 G
PCV valve cover gasket: 06F 103 483 E
PCV valve cover to turbo hose: 06F 103 215 A
PCV tube to turbo metal gasket: 06F 145 757 F

-If you did the DH pcv fix, and you have a rear pcv failure, then you will need to change the tube labeled as "Exhaust turbocharged gas outlet" showin in the pic above. the Part #'s are the last two shown above (06F 103 215 A & 06F 145 757 F)

3. Broken intake ducting

Background:
Some people have reported that part of the intake ducting that connects to the stock engine (the part in front of the accordion section) breaks off and gets lost, or worst, gets stuck and/or shredded by the fan. Due to its location, the loss in power should be minimal.

(IMG:http://www.swankmonkey.com/vw/jetta/2006/images/engine_cover/intake_cover_damage.jpg)

Symptom:
-You may notice that part of the ducting is missing.
-You may see shreds of the ducting in and around the fan.
-You may see the coolant temps rising possibly due to a part of the intake ducting getting stuck and not allowing the fan to turn. If the coolant gauge goes into the red, then immediately shut the engine off, and check to see if the fan is operating.

Solution:
-If the fan is damaged, then you may need a new fan.
-An aftermarket intake will replace the ducting section, and is a possibly solution.
-You might be able to tape or epoxy the sections together, so that it will make them harder to come apart. You may also remove the top piece alltogether.


4. Cam lobe wear
Background:
Excessive wear of intake camshaft lobe that drives the high pressure fuel pump. The wear limits maximum pump piston lift, causing fuel rail pressure fluctuations. The intake cam drives the fuel pump:

(IMG:http://img.photobucket.com/albums/v406/dpham00/fuel20pump20-20cam20lobe.jpg)

Please see also #5 below.

Symptom:
-Fuel cut-out when driving, esp. under WOT.
-Fuel cut-out symptoms range from soft pulsations of power to long-pulse bucking while in high-gear high-load situations (high gear at WOT, or up a grade). MIL may flash if cut-out is severe. Car will also go into hard-limp (no boost, 4500RPM limit) if severe enough.
-MIL ON
-P0087 Fuel Rail / System Pressure - Too Low
-P1093 Fuel Trim 2, Bank 1 Malfunction
-P2293 Fuel Pressure Regulator 2 Performance

Solution:
Increase surface hardening of camshaft lobe for the high pressure fuel pump. Improved intake camshafts have Part No. 06F109101B. Refer to TSB# 15 07 04

5. High pressure fuel pump failure

Background:
The high pressure fuel pump sometimes is not able to supply enough fuel, especially at low to mid range RPMs because it is cam driven. Please note that the high pressure fuel pump is different than the in-tank fuel pump. Please see also #4 above.

(IMG:http://img.photobucket.com/albums/v406/dpham00/fuelpump.jpg)

Symptom:
-Fuel cut-out when driving, esp. under WOT.
-You may see the following DTC
004767 - Low-Pressure Fuel Pressure Regulation: Pressure too High
P129F - 001 - Upper Limit Exceeded - MIL ON

Solution:
-If you are chipped, then try to put the car in stock mode to see if the fuel cuts will stop. If it does, then you might want to wait until a fuel pump solution comes out. APR and Autotech are currently working on solutions.
-If you are stock, then it is possible that you have a bad fuel pump. The dealer should replace this under warranty.

[Dr.Silviu]

Un articol interesant despre catch-cans:



Why Use a Catch Can?
An excellent article on the benefits of running a catch canfrom redline-motorworks.

How does an oil catch can work and why is it beneficial?
Last Updated: 7/28/2010
There is a large debate as to whether or not oil catch cans are worth the money or not. This article is dedicated to providing a very detailed explanation showing why a catch can is highly recommended in direct injection engine applications.

First, let's go over what is currently happening in your engine without a catch can installed. All internal combustion engines that run off gasoline are 4 stroke engines. This means that the piston has to go up and down a total of 4 times to complete a cycle. The piston first goes down with the intake valves open creating a vacuum. This draws in the cool dense air for combustion. At the same time, fuel is injected into the cylinder. The intake valves close and then the piston rises up towards the top of the cylinder. This compression creates an immense build-up of pressure in the cylinder. The only things containing this high pressure are the cylinder itself, the piston and the piston rings that seat against the walls of the cylinder. The intake and exhaust valves are obviously closed as well. The pressure is so high that a very small amount of the air escapes around the piston and piston rings into the crankcase. This is called blow-by. The amount of blow-by increases as the engine RPMs rise. Also, an engine with more cylinders will have more blow-by. Obviously not all of the air escapes or else combustion wouldn't take place. A diagram of the 4-stroke cycle can be seen below. Only the first 2 steps are relevant in regards to the catch can.

(IMG:https://www.redline-motorworks.com/v/vspfiles/assets/images/4-stroke-process.jpg)

Inside the crankcase, you have the crank which is turning in the oil pan which is full of oil. This keeps it properly lubricated. PCV or positive crankcase ventilation is necessary to ensure there isn't a build up of pressure in the crankcase. This would cause the crankcase to possibly crack under the pressure and create a huge mess of oil on the street. So the PCV system removes the pressure from the crankcase and reverts it back through the intake tract via crank case vents. This pressure isn't made up of 100% air. It will also contain a very small amount of oil as well since there is so much in the oil pan at a high temperature. This air and oil mixture is then entered somewhere after the intake system, passes through the intercooler (if you car is turbo or supercharged) and then re-enters the combustion chamber (cylinder) through your intake valves to be re-burned. The oil will actually coat everything on its way back to the combustion chamber. It will develop in the intercooler, boost hoses, intake manifold and intake valves. Just on the other side of these valves is where the combustion is taking place where the temperatures are extremely high. This is what actually causes the oil to solidify on the valves. With the oil passing through the intercooler, it can actually coat the cooling fins which will hinder the intercooler's ability to cool the air therefore lowering the efficiency.

The caking on intake valves is only a problem with direct injection engines. For all other engines that use port injection, the gas is introduced before the combustion chamber which means it flows over the intake valves and enter the combustion chamber premixed with the air. This action of the fuel flowing over the intake valves actually cleans the valves from any oil that make already be on there. The oil never has the chance to cake on the valves in port injection engines.

Having oil caked onto your intake valves can cause the following symptoms:
Knocking
Pre-detonation
Loss in power
Loss in fuel economy
Here is an image of carbon build-up on valves. Yes, it's nasty.

(IMG:https://www.redline-motorworks.com/v/vspfiles/assets/images/caked-intake-valves.jpg)

This is mainly due to the fact that the air that comes through your intake system and goes into the combustion chamber won't just be air. It will contain some oil particles which cause the combustion process to be slightly less efficient.

You might ask why do car manufacturers revert this crankcase pressure back into the intake tract? Well, for starters there isn't anywhere safe to revert it to and you can't expel it into the atmosphere because it's not environmentally friendly and is considered to not be street legal.

Another question that arises is why isn't a catch can included from the factory? Well it's pretty simple actually. Most people don't even change their oil (scary but true) so will they think to empty the catch can regularly? The answer is obviously and unfortunately, no.

An oil catch can does just that. It catches or prevents the oil from re-entering the intake tract. A catch can is placed right after the PCV and before the intercooler. This means that a more pure (sometimes 100% pure) air mixture will go through the intercooler and intake valves. A more pure air mixture entering the intake valves means no caking and none of the symptoms listed above.

An oil catch can typically uses steel wool or a baffle system that removes the oil from the air-oil mixture. Higher quality cans use the baffle systems since it is less messy and better at separating the mixture. The oil falls to the bottom of the can where it is stored until the can is emptied.

An oil catch can doesn't add any power or make any cool noises so it is often overlooked when modifying vehicles. However, a catch can will ensure you are always running the most power possible by having a cleaner intake tract free of oil.