So after blocking the EGR and fitting a catch can I decided to remove the intake and clean it out. Not being a mechanic and not wanting to do any damage i took my time and the whole job and it took about 5 hours. Thanks to Rogazz for lending a hand while putting it all back together. The only tools we needed was a set of ring/open ended spanners(10 mm, 12 mm and 14 mm), socket set(10 mm, 12 mm and 14 mm and extension bar), pliers and a torque wrench.
The car has just over 50,000 km on it and has had the catch can and blanking plate for around 10,000 km.
Please excuse the 2 blurry photos.
Firstly i downloaded the workshop manual from the net and had a bit of a read.
Then I disconnected the battery and pipe from the intercooler to the throttle body to make some space to work in.
After that i disconnected the wiring harness from from the fuel pump, EGR, alternator, intake temp sensor and two plugs at the rear of the motor. I didn't remove it completely just enough to be able to lift it out of the way while removing the inlet. All the plugs are different shapes so they could only go back onto the correct plug.
I also had to remove the vac line that runs across the rear of the motor. Once this was done i removed the bolts that hold down the intake and lifted it out. The intake on these motors have 2 inlets to each cylinder.
Once I had it off the car I found that there was a significant build up of oil and carbon in the inlet. Because of the design of the inlet and the way the air flows into it, the front two cylinders were coated with about 1.5 mm of the black paste. The rear two cylinders were substantially worse with around 4-5 mm thick coating in some places. The rear two inlets were probably on 85% of the size they should be when clean.
This is the buildup inside the EGR valve
At this point I diluted some fairly strong degreaser and sat the whole intake in a large bucket and started to clean all the inlets. This process took around an hour and a half. I used tooth brushes as they where able to get in and bend around quiet a long way into the main plenum. I soaked the the whole inlet in the diluted solution and then used a pressure washer to remove as much of the coating for in the inaccessible parts of the inlet until the water flowed out clean. Next time around i will invest in a parts washer for this part of the job.
After the clean. Not 100% but much better.
To re install everything was a fairly quick process just a reverse of the order we disassembled everything. The only difference is that you need to use the torque wrench to bolt down the inlet manifold. this is where you need to have your workshop manual as it tells you the correct procedure, order and torque settings for the 12 bolts that hold the inlet down. Its a must to follow this order otherwise you run the risk of damaging the inlet and possibly striping out the treads in the head.
After starting the car again and everything worked without engine light
I noticed that the idle was smoother than before. After a test drive i didn't notice any power increase but I did notice that under load when the turbo was working hard that the car seemed to pull harder. I will report in a week or two if i have noted any change in fuel economy also.
I'm very happy i have done this and i will probably do it again when the car gets up to 100,000 km and see if the blanking plate and the catch can have helped keep the intake cleaner.
One thing i did note is that from the intake through to the valves in the head were still very dirty but there isn't much you can do to clean that out so for the time being it has to stay that way.
The car has just over 50,000 km on it and has had the catch can and blanking plate for around 10,000 km.
Please excuse the 2 blurry photos.
Firstly i downloaded the workshop manual from the net and had a bit of a read.
Then I disconnected the battery and pipe from the intercooler to the throttle body to make some space to work in.
After that i disconnected the wiring harness from from the fuel pump, EGR, alternator, intake temp sensor and two plugs at the rear of the motor. I didn't remove it completely just enough to be able to lift it out of the way while removing the inlet. All the plugs are different shapes so they could only go back onto the correct plug.
I also had to remove the vac line that runs across the rear of the motor. Once this was done i removed the bolts that hold down the intake and lifted it out. The intake on these motors have 2 inlets to each cylinder.
Once I had it off the car I found that there was a significant build up of oil and carbon in the inlet. Because of the design of the inlet and the way the air flows into it, the front two cylinders were coated with about 1.5 mm of the black paste. The rear two cylinders were substantially worse with around 4-5 mm thick coating in some places. The rear two inlets were probably on 85% of the size they should be when clean.
This is the buildup inside the EGR valve
At this point I diluted some fairly strong degreaser and sat the whole intake in a large bucket and started to clean all the inlets. This process took around an hour and a half. I used tooth brushes as they where able to get in and bend around quiet a long way into the main plenum. I soaked the the whole inlet in the diluted solution and then used a pressure washer to remove as much of the coating for in the inaccessible parts of the inlet until the water flowed out clean. Next time around i will invest in a parts washer for this part of the job.
After the clean. Not 100% but much better.
To re install everything was a fairly quick process just a reverse of the order we disassembled everything. The only difference is that you need to use the torque wrench to bolt down the inlet manifold. this is where you need to have your workshop manual as it tells you the correct procedure, order and torque settings for the 12 bolts that hold the inlet down. Its a must to follow this order otherwise you run the risk of damaging the inlet and possibly striping out the treads in the head.
After starting the car again and everything worked without engine light
I noticed that the idle was smoother than before. After a test drive i didn't notice any power increase but I did notice that under load when the turbo was working hard that the car seemed to pull harder. I will report in a week or two if i have noted any change in fuel economy also.I'm very happy i have done this and i will probably do it again when the car gets up to 100,000 km and see if the blanking plate and the catch can have helped keep the intake cleaner.
One thing i did note is that from the intake through to the valves in the head were still very dirty but there isn't much you can do to clean that out so for the time being it has to stay that way.
