1JZ Cressie problems

[89supra]

Hey all,

Just had some problems start to arise with my 1jz cressie and was wondering if anyone can help remedy them.

First problem is that the engine has recently lost its cold start idle up. It used to do it now it doesnt.

Second, for about the first 10-15 minutes of driving if I give it anything over half throttle it starts to cough, splutter and miss big time. It will puff out clouds of black smoke when it does too. After its reached normal driving temp the car pulls like a freight train... I have changed the coilpacks with known working ones, igniter, new plugs (BKR6e's) and the car still carries on. Next step is to replace the O2 sensor and cross my fingers.

Engine is out of a Jzx90, auto, dumps, 14psi, fmic, stock ecu.

[Cuzzo]

capacitors leaking inside the ecu?

[orangeute338]

have you checked the tps? i have a simlar problem and it got better after i adjusted the tps but now has come back, when cruising and push the pedal down it feels like its over fueling or has no timing and wont go anywhere but the boost will rise to about 5psi then suddenly wakes up and goes like normal. it was doing it then i adjusted the tps and made it worse to the point you put the foot down and its spatters and would back fire then wake up and go like normal, so i adjusted it again and worked good then had some problems where busted a rad hose and got pretty hot and now the problem has come back, i just adjusted the tps and i made it a bit worse again...whats the correct way to adjust the tps on 1jz? i found a online a walkthrough and followed that adjusted so reads on the ohms at .55mm feeler gauge and then nothing at .7

[pandaah]

Sounds like a coolant temp sensor problem to me, on the top radiator outlet on the engine there are two coolant sensors, one single pin and a twin pin sensor, its the twin pin one that sends a signal to the ecu that malfunctions in the way you describe, change that first bud

[orangeute338]

yeah i might have to change that sensor prob died when got hot. Noticed this morning i dont have cold start either and unplugged the sensor and nothing changed. So does that affect the throttle? Cruising at light throttle then push pedal down slowly wont move and once moves past half throttle goes fine. I adjusted tps yesterday but this morn felt worse then before i moved it.

[dumbass]

like cuzo said have u checked capacitors
never ever seen a coolant temp sensor fail in all my life on a toyota
maybe unplug coolant tenp sensor see if it helps or makes it worse
if it does do somethign different then u know temp sensor works

no cold start is also caused by fkt capacitors

[orangeute338]

i had the ecu apart a few weeks ago to check them and i looked brand new its from 93 soarer. i just checked engine check codes had 22 which is meant to be temp sensor i did quick search on Google. And checked the resistance at different times and is good to specs so its workin properly. Maybe theres a bad wire there. Ill check the voltage at ecu and plug later. When first started car this morning pulled plug off temp and didnt change the way it idled.

[JZA70R_92]

even though they look ok on top check the board for any leaking black stuff near the caps and a fishy sorta smell..Just fixed a 1JZ ECU 2 days ago and from the top it looked fine but when taking the caps off shit had leaked and the "leg" end of the capacitor had burst.

The car had the same issues your having!!

[orangeute338]

just pulled it out and had a look all looks new still even green paint on tops of caps none leaking. Reset the codes so ill see what comes up. Would bad battery cause problems like that? Its on its way out so might try change that see if it helps

[orangeute338]

when i left work had the engine check light on the whole way, got home and realised i hadnt pushed the temp sensor plug back on, plugged it on and check light went away, that made me realise why i had the code 22 earlier, because this morning i unplugged it while car was running to check if it made a difference. so my sensor is working fine, i think it might be my tps that is playing up/ not adjusted correctly, i found another thread and someone said that the ecu only knows cruise and wot, over 50% throttle runs closed loop or whateva, so my car goes perfect over 50% throttle but over fuels under that so why that happens i have no idea...there was a thread a few months ago by Z2TT with simlar probs of low idle cold start etc

this was what someone said about the throttle position

From my watching of an o2 sensor, there are really only 2 points on the TPS.
One for 'cruise' AFR's.
One for 'WOT' AFR's.

At about 50% (roughly speaking) the AFR's will drop from 14.5 down to about 12 in almost a switch like fashion.

Most of the calculations will be done via AFM and RPM.

[Hiltz]

What you are reading from the o2 sensor is normal. A o2 sensor reads the burnt fuel exhuast gasses so the ecu knows its suppling the correct amount of fuel to the engine.A lean mixture during light throttle /cruize is normal, as you apply more throttle % and load. The ecu will richen up the fuel trim to help spool of turbo's and be ready for boost pressure in the cylinders.I don't think theres anything wrong with your o2 sensor. Sounds like you're ecu is giving you troubles.
When my jzx81 ecu packed it in,it would neally flood the cylinders at cold start,wouldnt idle then hard to start.
Swap/Borrow a ecu from someone local to see if that fixes or eliminates that the ecu is the problem.
These ecu's are 20+ years or older now remember.
Good luck.

[orangeute338]

i was just quoting what someone else had said about the throttle and cruise and wot, i havnt checked my afr yet, i was just saying that if thats the way the ecu works then atm from 50%+ throttle my car is fine its just at anything below 50% its crap. but i think the cold start prob was the plug had come off, it has a broken clip, now i reset the ecu and plugged it back on the car starts up fine, havnt driven it to see if its still playing up at light throttle, i read something about the iscv valve so maybe that was playing up so going to pull that off and clean it. im pretty sure its not ecu and its the tps because it got worse when i adjusted it, and the few weeks ago it was crap then adjusted it and got worse then adjusted it again and came good. so might try adjust it again and hopefully it will come good...might put my wideband in the exhaust to see what the a/f are doing to try work out the prob...

[Hiltz]

Yeah ok fair enough, Give iscv a good clean out, trying swapping the sensors you mentioned.You might aswell try another ecu.
A friend recently had simalar issues with his jza70 wouldnt load up properly. He tried coils,map sensor and tps and it ended up have 3 leaking caps in the ecu.
Hopefully you can sort it out dude.

[JZA70R_92]

just to clarify the caps in the JZA70 ecus dont have that green mark....the caps to check are the cylinder shape looking.

15uf, 33uf, 47uf, 100uf and 220uf.

[orangeute338]

yeah i have jzz30 motor and box and ecu, was just saying they are that new looking that they still have the green paint on the top, if they had ot burnt out that would prob burn off...