Well, I bought this thing with blown turbos and it came with a new set, so I installed them this weekend. Aside from being time consuming, it really wasn't very difficult. My stock turbo manifold was cracked horrendously. In any case, I replaced the turbos and the spark plugs (which were terribly oil fouled from the blown turbos). The car runs MUCH better, but I'm having some boost problems. The 1st turbo works great, I'm seeing right around 10-11 psi. When the 2nd turbo want to kick in, thats where the problems start. I get a big boost spike to 14psi and then it falls down to 7 psi. I suppose that I must have a vacuum leak somewhere. The car also idles very rough, but seems to run fine otherwise. It idled rough before the turbo swap as well.

In summary:
1) Any ideas on the boost spike?
2) rough idle

Mods:
DP
MP
CB

EDIT - as far as the boost issue goes, I might just go nonsequential and be done with it.

 

Just a guess, but it is probably your mods - I would get a computer upgrade or put the stock cat/ cat-back on till you can deal with fuel/ intake requirements.

 

Your problem has nothing to do with being sequential or not. First of all, the 14 psi spike is typical with running a full open exhaust, although the drop to 7 isn't. That sounds like a missing pill or a small boost leak.

Also, running a full open exhaust on the stock ecu without strictly maintaing boost to 10 psi is not good. Have you checked the compression of the motor? Does the car still pull strong?

Your bad idle could be due to a number of things, but I'm guessing the air pump has been removed. The FD relies on the air pump at idle and low rpm to add additional air to the intake. Without the pump, the car can run way too rich at idle and low rpm and may run like ****. You will also continue to foul plugs. Either get a stand-alone system like Haltech or Power FC or put a cat and air pump back on the car.

If you still have the air pump, your rough idle could be due to other things like bad wires, bad O2 sensor, etc.

 

Non-Seq might help the problem, however, you'll still need to deal with the boost spike/creep.

The problem is the midpipe. You are going to need to add restrictor plates on the exhaust, port the wastegate, or switch on a cat to keep the boost under control.

 

The boost wasn't creeping, it was spiking. I do agree though, I may have issues when I go non-sequential. Right now I have the silencer (read: cork) in my apexi exhaust. I do plan on adding a cat though, I need to pass emmissions!

 

The problem is that you don't know if it was creeping or not since you can't hold boost. So, once you fix the problem, that spike may not be a spike anymore (if you know what I mean).

Right now, I would say running that mp and hitting 14 PSI on the stock ECU should be your first priority.

 

What kind of vacuum are you pulling at idle?
Jim

 

Agreed. I was planning on adding a cat this week.