1JZGTE problem, rev limiter/ idle

[GZP51]

well i will have a look at the fuel pump today and see what i can ascertain there! so i need to find a jza70 map sensor... that is the one with the green label? any suggestions where i can get one of them from? any numbers you guys could give me?
cheers
matt

[manny]

Plugging the PFC back in will give a voltage/value/reading for every sensor attached to the engine including a voltage and psi reading for the MAP sensor.
I've posted up the knock sensors test specs here before if you wanted to test them, but I highly doubt they are the culprit here.
Fuel pumps just age, wear and have a reduced flow output - don't know that blowing compressed air into one will achieve much???
If you could check fuel rail pressure at least, you'd have an idea if it had 50+psi once you're on boost.

[GZP51]

ok i am still hunting the elusive fuel pump, anyone know how to access it in a gz20? i basically want to pull it out check the screen on it and make sure the little fucker isn't totally junked up... few more days till i can afford a new pump :S
cheers
matt

[SL666]

could also be a shagged FPR.. you did double check the vac lines aren't blocked off on that didn't you? and that it sees proper boost/vac signal?

[urantia]

ok i am still hunting the elusive fuel pump, anyone know how to access it in a gz20? i basically want to pull it out check the screen on it and make sure the little fucker isn't totally junked up... few more days till i can afford a new pump :S
cheers
matt

If it's anything like mk3 supra, you'll have to undue your fuel lines to the tank, drop your whole fuel tank, then you have access to the fuel pump.

Would of been so much nicer if toyota just left a window in the boot to access the fuel pump and fuel lines.

[GZP51]

i have found that it is indeed like the mk3 supra and that you do have to drop the fuel tank out of it, therefore it is staying in and i am not touching another thing until the dyno when i will hopefully be told what all my car problems are
cheers
matt

[JustCallMeOrlando]

Change it anyway. It's not *that* hard and you probably should have a decent fuel pump just for piece of mind. It's been around 15 years or so, it probably needed replacing anyway.

[White Knight]

The access to the fuel pump on the tank is just to the left of the access hole for the fuel sender/float. If you put you finger in there you can feel the lid.
You know what I did to my GZ20 to change the fuel pump to a Bosch 040? I just grabbed some tin snips and cut the section of boot out above the fuel pump so I could get to it with the tank staying put. I'm going to put a little hinge on the cut out piece and make an access lid that way.

[GZP51]

ah ok, so it IS possible to get to it without removing the fuel pump as long as you use tin snips hey? well that is always an option than. i am basically waiting to see how much i get paid tomorrow as i have not been to work all week and have used some of my holidays but i have no idea if i can even expect a normal weeks pay, if i do get it than a fuel pump will be on its way, but it won't be here till after the dyno anyways. i can still see the point of replacing it just for because, as manny said it is good insurance! and yes it is almost 20 years old!
cheers
matt

[GZP51]

btw i have picked up a 3 bar map sensor that i am going to try and use with the power FC. thought may as well! anyone know if this will not work? it is a simple external GMH (i think) map sensor!
cheers
matt

[manny]

btw i have picked up a 3 bar map sensor that i am going to try and use with the power FC. thought may as well! anyone know if this will not work? it is a simple external GMH (i think) map sensor!
cheers
matt

Doubt it - the Power FC has an optional 3 Bar MAP sensor available for it, for which it is pre-calibrated.
The selectable MAP options are the standard one, an SW20 20 psi one or the Apexi 3 Bar unit.

[chris davey]

Manny: why would it matter? As long as it is a 0-5v unit and the PFC will just be in a different part of the map as it thinks it has a 2 bar MAP or whatever. I thought you could just leave the MAP settings alone and mathematically work out what each load point is. That is what I did when I went from 2.5bar to 3 bar map with the wolf. It is easy as, just do up an excel spreadsheet with the old values and new ones. By fitting a 3 bar map you are reducing the tuning resolution (larger difference in load points) but you can then tune for high boost in the future.

Oh yeah and don’t all map sensor have 3 wires, gnd, 12v and signal. If this is the case and the signal is the same 0-5v I really can’t see how it couldn’t work?

I suppose we will see how it goes anyway

[manny]

Chris

The Power FC isn't that simplistic and the MAP sensor is fundamental to it's proper operation. Different MAP sensors have different response curves and voltage is not directly proportional to boost or even linear in all MAP sensors. eg, the Power FC's correction tables will expect the transition from vac to boost at a pre-set voltage for the 3 pre-set and mentioned Denso MAP sensors but of course with another unknown/uncalibrated MAP like the Delco, it will not happen where it expects it and it will throw out the many hard coded pre-set tables/calculations and it won't even run on the base map.

If you had access to the FC Pro software and adapter and shifted the axis points about, you'd still have a hand controller displaying incorrect realtime and peak boost/vac values and their dependancies which would make subsequent diagnosis difficult by having to repeatedly refer to an printed excel spreadsheet for cross reference and cross calculations.

Having used a Power FC in my Soarer for a few years and having experimented with the standard 1JZ 14psi, 2JZ 18psi, 3S 20psi and Apexi/Denso 3 Bar MAP and dealing with the hassles with the uncalibrated Supra/2JZ 18 psi unit even with me having the Apexi FC Pro tuning software/adapter, I'll take any of the 3 available preset options and in particular the Apexi 3 Bar MAP any day for simplistic ease of use and guaranteed results.

Is the hassle worth it for the sake of buying a cheap Delco MAP sensor? That's up to Matt to decide and deal with I guess.

[chris davey]

Nope, not worth it then. I want my Map sensor back Matt!

[GZP51]

of course you can have it back chris
manny thanks for the informative response, i was thinking (read hoping) that with another map sensor that it would alleviate any possible issues between the power fc and the map sensor as i knew that they could take a 3 bar i just did not know that they had to be so specific. by what you are saying i DO NOT want any more hassles than i already have lol!
Only another day to go until i will have the fuel system results in. which means hopefully only another day that i have to baby my car around and ducking my head whenever i pull up beside a skyrice or wrx LOL! ooo i can't wait to humiliate or be humiliated LOL
once again thanks for the info and chris i will probably drop the map in to you tomorrow if there will be anyone home or if you want it in the letterbox let me know mate ;-)
cheers
matt