msp ecu PULLS fuel????????

[Little Beavis]

I put a MSP ecu in my car and took out the voltage clamp. . .

Go into boost, AFR starts to drop then goes lean. . .then you hit about 4300 rpm and pig rich!

I don't get it! It acts just like my MP3 ecu. . .maybe it IS the same. (Actually it clearly indicates msp on the eec-v box).

Any ideas of what is going on? I can put in the voltage clamp or the MPI turbo module, but I was curious how it would behave without it. . .now I'm just plain confused!

 

[Bigg Tim]

I put a MSP ecu in my car and took out the voltage clamp. . .

Go into boost, AFR starts to drop then goes lean. . .then you hit about 4300 rpm and pig rich!

I don't get it! It acts just like my MP3 ecu. . .maybe it IS the same. (Actually it clearly indicates msp on the eec-v box).

Any ideas of what is going on? I can put in the voltage clamp or the MPI turbo module, but I was curious how it would behave without it. . .now I'm just plain confused!

Sounds like it's pulling fuel in closed loop and adding once you go into open loop. There's no way for the ECU to see boost, there's no MAP involved, unless it uses voltages to determine when it's in boost.

So it's lean at your max psi until 4300 rpm, what psi is that? How the hell do the MSP keep running if they are lean until open loop? Maybe that's why they only come with like 5psi. Nick said that at couple of psi doesn't matter if you are lean, you just don't want to stay lean.

The MP3 ECU doesn't put you as rich as the MSP one does it? How's the timing differences?

 

[igdrasil]

Hows your map on your MPI tunner now with the mazdaspeed ECU?
Do you have your MPI controlling the stock injectors?
Im curious! Give us some details!

 

[505zoom]

Sounds familiar... welcome to my world, lol.

 

[Little Beavis]

Yeah, I thought the msp was supposed to be so damn rich. . .but it isn't. . .at least not in closed loop. . .once it hits open loop, I could fuel two cars. . .but not until then.

Igdrasil, I haven't had time to tune it completely yet. . .but it is SO rich in open loop!

 

[505zoom]

Yeah, I thought the msp was supposed to be so damn rich. . .but it isn't. . .at least not in closed loop. . .once it hits open loop, I could fuel two cars. . .but not until then.

Igdrasil, I haven't had time to tune it completely yet. . .but it is SO rich in open loop!

Now you know the feeling of the msp. When I didn't have a wideband, I could feel everything you described in your first post. After going WOT you feel it go lean as it surges a little bit... then you hit open loop and feel it surge again. Very pulsy, inconsistent acceleration.

 

[DooMer_MP3]

LOL, what a piece of s***.

 

[igdrasil]

yeah well...thats interesting...then mazda did only added lots of fuel on open loop. Maybe the open loop comes sooner?

 

[DooMer_MP3]

Aren't there more changeover-to-open-loop points on the MSP ECU? With the P5/MP3 ECUs, its like 1 or 2 variables, while the MSP has more, hence the eManage problems etc.

Chris

 

[Little Beavis]

Not sure. . .I do know that if you clamp the O2 you can add the fuel you need. . .but I'm having issues pulling fuel up top. . .there's just too much damn fuel. I have to say I'm kind of disappointed in the mapping of the msp ecu. . .but I think it would allow a car on stock injectors and the MPI to run probably 15+ psi now (based on MPI's latest work).

I just need a co-pilot to finish tuning it. . .

 

[acidbug]

Interesting

*subscribed*

 

[DooMer_MP3]

Not sure. . .I do know that if you clamp the O2 you can add the fuel you need. . .but I'm having issues pulling fuel up top. . .there's just too much damn fuel. I have to say I'm kind of disappointed in the mapping of the msp ecu. . .but I think it would allow a car on stock injectors and the MPI to run probably 15+ psi now (based on MPI's latest work).

I just need a co-pilot to finish tuning it. . .

Move back to the cool side of the border and you got yourself a co-pilot .

Chris