Remove unnecessary stuff out of the engine bay and relocate coolers.

Posted by martin on 12 September, 2007 17:24 | Permalink | Engine | Hits (1710)

You might have noticed that I've removed N249 and vacuum reservoir. And I relocated the N112 value which controls the EGR valve for the Secondary Air Injection system. It does make the engine bay much cleaner and it would be super easy to check and swap spark plugs.
updated: I removed N112 also. and note, you can replace both N249 and N112 with 30ohm/10w resistors.

And the vacuum reservior is working with N249, once you remove N249 you can actually remove the vacuum reservior. Want to remove N249? Check my post I made more than two years ago. Click here. The first paragraph is exactly telling you how to remove N249.

If you really don't know what N249 is,  then just read document below.

updated: more detailed info and diagram: 

Here is quote from one post in ""

N249 is controlling the DV (Dump Valve). It is installed between the intake vacuum source and DV itself. When no current is switched to the N249 (default state), the DV will get vacuum or boost from the intake manifold. This is how almost ALL turbo cars are worknig. When shifting gears, you let off throttle, TB closes and vacuum is generated which can open DV to vent boost (which cannot enter engine, because TB is closed).

On never 1.8Ts (2000+) they introduced the N249 (along with lots of other stuff) which is a possibility for the ECU to open the DV any time (!), even during full throttle/acceleration. When the engine is running and turbo is boosting, there is no vacuum generated, but to open the DV (which is mechanical), vacuum is needed. This is what the black vacuum reservior on top of the engine is used for. When idling, shifting, etc - so when vacuum is available, vacuum is led into this reservoir from the intake manifold and kept inside using a check valve (white/black), so when boosting again, vacuum will stay there (air cannot enter into the reservoir).

When ECU wants to open DV durnig full throttle/acceleration, simply "energizes" N249, which will "de-select" the DV from the intake manifold (boost), and "switches" it onto the vacuum reservior. The vacuum in the reservoir will open the DV instantly and release your boost, which, in most of the cases (tuning, etc) is not that highly required. In the case ECU sees a little overboost problem, it can turn N249 on/off repeatedly for very fast (just as N75 is working), which will open/close DV all the time, trying to settle (lower) the boost level.


Yet another shot from different angle.

Earl's plumbing to crank case breather and cylinder head breather. Isn't it looks nice even I have not finish it yet. :)


Relocated Oil cooler. I intentionally placed it a bit declivous to get more air pass through it.


And here is my brand new b-ling* b-ling* HKS intercooler. Yes, I upgrade it a bit bigger.

Once I have this Sportec bumper installed, I noticde that the water temperature of ther radiator lows around 10 to 15 degree as the air way is double and more than it used to be. I thought it is about time to upgrade the intercooler a bit.

And hopefully the water temperature of radiator would not get higher than my first FMIC I bought long long time ago. My first FMIC made the water temp about 10 degree higher than stock range. I noticde that my first FMIC is not so good to let cool air pass through itself to the refrigerant condenser and the radiator right after the intercooler. It is why I changed a smaller one, my 2nd FMIC, to make sure the water temperature won't get so high. 

After doing some research, I noticed that the HKS intercooler has higher efficient to cool the air for engine and it also lets cold air pass through itself very fast to cool down the refrigerant condenser and the radiator. As it probabaly would just raise the water temperature about 5 degree as it is much bigger than my 2nd FMIC, but it would still get 5 to 10 degree lower than it used to be as I have the bumper upgrade with big air way now. It is really not a very bad upgrade of FMIC, isn't it?

I really hope this 3rd FMIC would be the best one and final one. Hopefully, I don't need to take care about the water temperature get higher than normal any more.


NOTE: To remove the Secondary Air Injection Pump (SAI), you need 330ohm/10W resistor.

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