1jz 1/4 throttle same as full throttle?

[naten]

hahahaha good on ya rob as if i even mentioned you.

As if i was scared, actually i was. Crazy hungarian man driving my car at speed through the nasho

I feel like such a noob, i guess the only way to learn is experience.

Excellent info thanks cruzida will fix it up now!

[JP]

just a thought...

Is the vac line on the fuel pressure regulator ok?

Had a 4agte do very similar things with the AFR when the FPR vac line fell off.

[whatthe?]

I'd be checking your fuel filter and voltage at the fuel pump as well. It's common to find a voltage drop of up to 3v in that run of wire in a MA61. A new pump wont help you if that's the case

[Wildsupra]

Man you must get some awesome economy outta that car

[naten]

JP: had already checked it couple of days ago when doing tps thanks for the suggestion tho

about average i believe 10-13 lp100kms under 10s if just on the express way

but i suppose that is under my daily drivers numbers

should rang some bells hey

[oldcorollas]

dumb question time...

are you absolutely sure that the fuel pressure reg is getting manifold pressure, and has no cracks or leaks? and is not on the bleed valve line for the wastegate?

that could be the reason that you have such crap AFR...

[naten]

yea i did a triple check just then, its plumbed off the plenum after the TB nothing else on that line. No leaks or cracks i can see or test (breath pressure)

unless the FPR itself is shagged.

I thought it was because im running the stock ma61 pump. It *might* be wiring if the voltage drop is bad enough. I knew either way the stock pump should be replaced so im not going to be pissed if its not that.

[CrUZida]

Unless the stock pump is uber fucked it should be more than sufficient to deal with up to 5psi of boost. ie cruise and low loads should be fine.

I definitely wouldn't want to run any more boost than that.
Especially when you consider the price of a Walbro vs the price of another 1jz.

However, if the line is kinked or blocked, or the filter is blocked, then thats an entirely different story.


Put new pump in, test.
If still back, test pressure in fuel rails.
If up to shit, replace reg.

[whatthe?]

The wiring was bad enough in both of my MA61s to cause issues. Takes 2 mins with a meter to check. You can get to the fuel pump plug on the tank by taking out 3 screws

[naten]

The fact that the pump and wiring is now 24 years old and done 350,000kms prob doesnt help either.

I cant remember how mos wired up my fuel pump but i think its through the normal fuse box in the engnie bay. Am i best to run a new relay off the battery and use that as the switch or just replacing that wire from the fuse box to the pump is enough?

I have a new fuel filter to put in at the same time. The fuel filter wouldnt be causing the restriction would it? its just a normal metal straight throught jobbie for EFI cars. Cant see it being an issue but you never know.

Either way new pump is going in so i may as well redo the wiring at the same time.

Fixed up the TPS too so all should be good on that side of things now.

Ill keep yas posted!

[whatthe?]

If Mos did the wiring it'll be via the circuit opening relay in the drivers side kick panel. It's the wiring from there to the pump which runs up the drivers side of the car that often gets dodgy. A nice heavy gauge wire from relay to pump will fix the issue if you notice voltage drop at the pump plug.

That being said a walbro is a no-brainer regardless of wiring condition

[naten]

Yea the wiring side of its a piece of piss just wasnt sure bout what bits to replace.

Thanks man! Ill probably replace it anyways just to be sure.

[naten]

Pump has been installed with much success!

The hesitation is gone and it pulls alot harder (i think rob will agree with that). I cant believe how much punchier it is now

The pump is seeing 12v so i didnt have to worry about rewiring it.

Clutch has started to slip on hard launches now so it looks like ill be up for a new one soon

Ill have to get it back on the dyno soon too.


Idle is still shitty though, i set the tps with the throttle 100% closed and it doesnt idle when coming to a stop. Im thinking ill just crack the throttle a bit and set the tps off that position.

Thanks everyone for your help and advice.

[CrUZida]

I'd reset the ecu after resetting the TPS/throttle to be 100% closed.
May take a bit for the ecu to realise how much air is required from the ISCV.

Failing that the dashpot isn't working properly.

[naten]

hmmmmm

i have reset the ecu twice since then. I just redid it as i said above and the normal nice idle is back but thats with the throttle cracked and the tps set off that.

The dashpot is the little black thingy that sits right next to the tps? It doesnt have any wires or anything else coming into it. By the looks of it, it just cushions the throttle closing but i might be wrong?