Too little boost, solenoid, MAP or something else?

[jimmydanny]

Nothing happens, it just peaks there and falls down fast as hell.

As for more petrol, without getting standalone or piggyback, can I go with a Supra fuel pump, 720 injectors and fuel pressure regulator while waiting for funds for standalone and mapping (which is, did I mention, 900km away)

[m1tch]

On stock fueling with a chipped ECU you can run to about 0.9bar and thats at the very limit of the stock fueling (the injectors are maxxing at 92% duty) anything more than 0.9 bar will shorten the OEM turbo quite a bit as anything more than 0.9 bar is outside its efficency window, also the fueling isn\'t there for anything more than that.

You can uprate the fuel pump no problem and get an FPR put in but for larger injectors you need a standalone or piggyback although I think you can get some standalone injector drivers which tweek the settings but they are pretty old. Its probably best to go with standard 550 primaries and up the secondaries to 800ccs.

What sort of power and turbo are you going for? Also, what are the AFRs at the moment?

[jimmydanny]

Next paycheck I am getting AFR gauge, my old one is done :/

Will the stock ECU cope with bigger secondaries then?

As for power, I have ordered the Racing Beat REV TII exhaust, and got a custom intake as well, so I will get some free boost there alone. But I wont go over 300hp without standalone, but as I said, 900km, 1000£ for standalone, same for mapping at least.

[m1tch]

You need the turbo wastegate ported if you are going to be making the system free flowing else it will boost creap badly, the ECU can\'t cope with bigger secondaries, I ran my car with 1680s in the secondaries on a stock ECU (until my emanage ultimate was connected up) it sounded like antilag going off at 3.5k and the whole car bogged due to the massive amount of fuel being injected lol

I would suggest stop playing with the boost levels and get the supporting mods in first, then when its safe to increase the boost you can without the engine going bang! I am guessing you are still running on an OEM plastic radiator and OEM HT leads?

[jimmydanny]

HT leads? As spark plug wires? Nope, running Mazdatrix ones. radiator though. But problem is not heat, and in Norway, it will never be.

As for boost levels I suggest you read the whole topic first, I am not getting my supposed boost level with the wastegate connected, I am lacking half my boost, which is either a problem because of the MAP, the duty solenoid, the ECU or the wastegate. With running 1,2 bar and it not behind boost creep, I proved nicely that the wastegate stays shut.

So back to square one. MAP, ECU or duty solenoid. I can\'t find my multimeter so I can\'t check for anything yet.

[jimmydanny]

Okay, weird part incoming now.

Measured over pin 3R to ground, got 3V when ign on, 2-4 on idle (jumpy idle), and 12V when over 2-3k rpm, no matter what boost/vac level.

Then I measured over the solenoid valve itself. I got 12V when idle, when reving to over 3k I got 0. How the :censored::censored::censored::censored: is the possible?

So, I ohmed over the L/W (blue/white) wire from the ECu to the solenoid, got a beep. Ohmed the other wire on the solenoid to the plus on the battery when ign on, nothing, 91 ohms. Then I took it over to the minus, got a beep. Tell me, are both connected to the ground?

And still I am getting a voltage, inverted on one side of the cable. This doesn\'t make sense for :censored::censored::censored::censored:!

[jimmydanny]

Also, can someone confirm these three? Volt on idle, pin 3R to gnd, 12V on rev.

Over the solenoid, 12V idle, 0 on 3k rpm.

Ohm the L/W wire, ohm/hear the beep. Ohm the other cable (which the FSM says goes to the main relay, so should be power when ign on) to the plus on the battery. Beep/no beep (ohm value). Then to the minus.

Thanks in advance!

[Prof]

The solenoid will be connected to 12v as will all the other solenoids - on one side, the other side will connect to the ECU pin.  Inside the ECU is a power transistor which is either off (open circuit) or on (shorted to ground).
 
If you switch the ignition key to ign setting but don\'t crank it, the solenoid should be at 12V on both pins, this is because the solenoid coil is a few tens of ohms and the transistor will be off.  When the ECU sees a rising voltage on the MAP sensor, it will trigger the solenoid to pulse (about 25 times a second) to regulate the boost.  The waveform is like a square wave, but the duty of the pulses changes, the effect is to give an average voltage - digital meters aren\'t really useful to see effect of this -  heavily damped analog meter will give a much better indication.
 
Be careful of measuring resistances with components stll attached in the engine bay, there are plenty of components that will give the impression that both supply rails are shorted to each other.
 
A healthy solenoid should give about 30-35 ohms resistance between the pins (with nothing else connected to it).
 
The manual says that the ECU will read 0v when the ignition is off on Pin 3R, and below 2.0V on idle.

[jimmydanny]

Ah, I have gone one year electrician at high school, no Ohming when connected!

But I asked this on rx7club, and will do here too... If I remove the solenoid, leave it hanging connected, and connect the two hoses together instead, I will get a vac leak through it, but it should be measured air, and it should give me 0,7 in theory, right?

[Prof]

Ah, I have gone one year electrician at high school, no Ohming when connected!
 
But I asked this on rx7club, and will do here too... If I remove the solenoid, leave it hanging connected, and connect the two hoses together instead, I will get a vac leak through it, but it should be measured air, and it should give me 0,7 in theory, right?

No - not quite - the solenoid is pulsed by the ECU, so it effectively controls the amount of boost it leaks off.  I don\'t think it\'s ever on fully.
 
If you plug the pipe that goes to the duty solenoid from the turbo you should see only 5 psi or there abouts, if you can rig up a bleed valve and adjust it to bleed a little air off, then you should be able to control the amount of boost upto the fuel cut limit set by the ecu (about 8.6-8.8 psi).

[jimmydanny]

I just took one of the hoses and connected it over the two pipes, and I got 0,7 bar, 0,6 sometimes, but still better than 0,4.

As for fuel cut, I have an Rtek 1.5 chip in it, so it wont be a problem.