Need 2JZGTE Help

[schanster]

ok guys thanks i'm going to say that it acts let its just losing power but only for the motor everything stays on and it acts like its going to die then is ok and sometimes its back and forth like one sec ok next sec it trys to die then at idle its running ok then trys to stall then ok then trys to stall. ac does not work right now and the iac valve has never worked. and remember this is only after the air temp has got hot in the mornings when its still cool it runs perfect.

[SilverMk2]

You should get the IAC valve working that's probably your problem. Its not that hard to properly wire these cars so everything works perfect. The +B and m-rel all need to be properly connected.

[lacrssgus14]

^^This^^. Plus is your VSS hooked up properly? There are a ton of little things that can be missed in a swap and can cause issues like this when added together.

[williamb82]

Guys, what are you going on about?
...intermittent attempt to shut off and you're having him check for BHG?
Glad you're not a MD; I'd hate to sneeze and get a colonoscopy...


Schanster, lets try to explain the symptoms a bit more if you would please.

Driving down the road, it tries to die on you...
...like all power lost temporarily? Short hiccup? 1-2 second power loss?

What engine vitals do you measure? Fuel pressure? Wideband AFR's?

--billyM

i didnt say to check for a bhg. i said if his engine temps are rising when the car acts this way, that my guess would be a bhg. however, i do not know if the engine temps are rising when this happens as he didnt answer it the first time i asked, and i still dont see the answer. not on this page at least.

[williamb82]

ok guys thanks i'm going to say that it acts let its just losing power but only for the motor everything stays on and it acts like its going to die then is ok and sometimes its back and forth like one sec ok next sec it trys to die then at idle its running ok then trys to stall then ok then trys to stall. ac does not work right now and the iac valve has never worked. and remember this is only after the air temp has got hot in the mornings when its still cool it runs perfect.

have you tried checking the engine codes to see if one is stored? and as mentioned before, make sure the iacv is working. iirc there is a thread talking about the +12v for it must be connected to constant power( i never looked into it to see why it was really needed). it was bumped in the last couple weeks so should be easy to find.

since you still never mentioned engine temp im guessing it must be fine during all of this. what fuel pump are you running? when the fuel pump in my 85 went out a few months ago, it acted similar to what you described and seemed to be ambient temp specific. mornings were fine. afternoons it ran horrible.

[SilverMk2]

...iirc there is a thread talking about the +12v for it must be connected to constant power( i never looked into it to see why it was really needed)....

It should be connected to switched power (technically the +B circuit) not the battery +12V. That's just a crutch.

[williamb82]

It should be connected to switched power (technically the +B circuit) not the battery +12V. That's just a crutch.

thats what i would do. use the m-rel to trigger the main relay as it should be, then power the b+ from the main relay. batt is the only one that should have constant power. but ive heard multiple people say it wouldnt work without constant power for some reason, and its in that thread i was talking about. for me its moot since ill be going megasquirt on my 2j swap.

[schanster]

i'm sorry williamb82 no the temp never changes. the iac valve has never work and i have not checked for codes the fuel pump is a walbo 255? i think thats what its call i really do thank u guys for the help

[BillyM]

First and foremost, check for codes. Second question, do you have a fuel pressure gauge in the cabin?

Take a chance to explain the scenarios when it acted like it was losing power (more interested in while it was driving, not so much while it was idling). ...go into as much detail as you can.

--billyM

[ihateu3]

It should be connected to switched power (technically the +B circuit) not the battery +12V. That's just a crutch.

Switched power turns the IACV off as soon as the ignition turns off, this does not allow the IACV to cycle back to a reset stage (the clicking noise you should hear on most toyotas after ignition is cut). If IACV is on a switched power, then the IACV will act in its last state (most likely warm) while trying to start, it needs to reset after every ignition cut. Factory wiring shows that the circuit for the IACV allows 3 seconds of power to the IACV after ignition is cut, thus allowing the reset procedure to incur.

I can personally verify that the 2jz does not want to stay running from a cold start with the IACV hooked up to swithed power unless you play with idle screws, give it gas and what not. I have not yet to find this 3 second delayed circuit wire, but I do know when I went with constant power the car started normal without need of any adjustments on the idle screw or applying gas. Downside to this constant power is that it drains my battery, so until I either figure out what wire I am needing for the 3 second power after cutoff, or I hook up a toggle switch, I am stuck with removing the constant power wire each time I shut my car off. This is one of the many reasons most standalone 2jz require idle screw adjustment and also manually giving the car gas to warm it up...