Post
by tenchu » March 23, 2010
Well to explain how the missing link works, you must know how a Honda map sensor works. Basically it reads the amount of vacuum in the intake manifold to determine elevation and adjust your map real time to compensate. Vacuum is the opposite of boost. When you go above 0 vacuum, you're into boost. The stock Honda map sensor doesn't know what boost is, so it freaks out when it reads it. The missing links job, is to prevent boost from traveling through the head into the map sensor, so the sensor will continue to read only vacuum. If you were to take off the missing link, and run the map sensor as factory, as soon as you hit boost, the map sensor would freak out, and put your car in limp mode (I went through this with my first turbo Civic). Assuming your missing link is working correctly (which I assume it is, you would normally throw a code for the MAP if it wasn't) then thats not an issue. A vacuum leak, or a crack in the manifold, is definitely an issue. As far as a dump tube goes, its not necessary, all it is going to do, is move where the wastegate dumps the raw unused exhaust, now, it is dumping it directly into your engine bay, the only real con, is the heat, and the carbon build up you will have in your bay. But its nothing to do with the issues you are having right now. As far as vacuum lines go, if you are going to tear it down till you get the parts to do it right, I would look into a Golden Eagle (or similar) vacuum manifold, and install it t'd off in your brake master cylinder vacuum line. The line from your wastegate should go to a vacuum line on the car (intake manifold, brake master cyl, etc). I always try to recommend the master cyl line to people who have the ability (or funds) to get their hands on a vacuum manifold, because it is the strongest vacuum source in your bay, which is important when you are running many things off your vacuum (wastegate, boost gauge, etc). NEVER, I mean, NEVER, T off of the map sensor vacuum, its too weak and will only cause issues.
If it wasn't for the cracked manifold, I would say start removing extras from the vacuum lines (boost gauge, bov, etc) to see if lack of vacuum is the issue, but you've got bigger problems to worry about. Also, I would definitely upgrade those injectors like you said you were going to.
Turbo cars are a lot of work and maintenance, there is a lot of extra strain on the car, and a bunch more things to break, or go wrong. But once you getting it running well and figure out how everything works, its a lot of fun.. I could never go back to NA.
Hope this helps, if you got any more issues or questions, feel free to ask.
this is her...