Low power - KJ swap

[DuRWooD]

Hey guys, I have a 2002 Protege 5 with a KJ swap with an MX6 transmission behind it. I just got running earlier today. The car is low on power, I believe it's to do with the factory boost controller limiting the boost, as if it were in first gear.

I'm wondering if anyone has any suggestions on what to do to get around this. I'm thinking worst case, I get a JET flash.

[bigb]

*bows*

that is quite the project if you have done that.

there is no boost controller on the KJ, only a bypass actuator like on most supercharged cars. it is either opened or closed. if the actuator is open because of a false ECU signal or it is damaged, you basically bypass the supercharger and it should feel like a naturally aspirated engine.

now since the 2.3 uses a "miller cycle" engine, it has delayed intake cam timing that normally the charger takes care of. if the charger is in bypass mode, the engine actually operates at 80% of the 2.3 volume.

aka it feels like you have a normal 1.8L engine in the car. Tiny tiny. is that what you are feeling? sluggish and no power? since the bypass valve is vacuum controlled you can probably force it. look for the ABV solenoid which controls this function or just hook up a vacuum pump to the line and try playing with it manually.

[DuRWooD]

Yeah, very, very sluggish. Really smooth however. There are no OBDII codes related to the bypass valve. I will try actuating it manually. If that works, if shouldn't be too hard to rig up a boost controller, thus avoiding having to mess with the ECU.

Here's a pic

I can't take credit for the swap though, I got it with the engine already in it, it just wasn't running right. I got it to run better, just stuck here for now.

[DuRWooD]

I'm going to try a new MAP sensor before I mess with anything else. I sort of rigged something up to work to get it running. It seems reasonable that that would be my biggest issue. After that, I don't know if it will give full boost, or just the limited boost. Time will tell, on the hunt for a new MAP sensor.

[bigb]

I have a spare MAP sensor and just about every other spare KJ part you could want from solenoids to pistons. Let me know if you are interested.

ps: dude that is a thing of beauty! wow... and I thought the millenia was cramped hehe.

[DuRWooD]

I would probably take a map sensor off your hands, what do you want for it? Before I do though, does anyone know the range of the S's sensor vs. a KL47 sensor? That's what I used to get it to work.

[bigb]

I'll check the shop manual and part catalog to see if they are the same part when i get home tonight.

as for the one I have, I can get it to you for $40 including shipping to Canada / USA.

[DuRWooD]

Cool man. If you can find me the stock range, I'll be able to rig up a programmable sensor temporarily while I wait for the proper one.

[bigb]

I looked through the manual and there is only a voltage measurement listed there. I can't seem to find it in terms of ohm. The sensor is also unique to this car since it has KJ stamped right on the sticker, so it is probably different than the 2.5 or other mazda sensors.

[DuRWooD]

I think I have the voltages figured out, the sensor I'm using is definately out of range.

I have a question about the factory boost control that might be unknown. Does the PCM limit the boost in park / neutral as well as first gear? Does anyone know what it does if it sees a TCM communication failure, does it limit the boost in this situation too?