VVT 1JZ intermittantly won't rev

[S_E]

So, got a JZX100 Chaser, engine is stock apart from EBC (usually turned off), pod and 3" catback exh.


Sometimes (maybe once a week, but it hadn't happened in about 3 weeks until today, and took ages to come back normal) the engine just won't rev, it'll slowly rev to 1600rpm and then stay there, let go of the throttle and it'll drop to normal idle speed, but hit the throttle again and it still won't go above 1600rpm. It'll still be smooth, If you're driving when it start happening, the revs will just keep dropping, if you try to drive from standstill even when it'll rev to 1600rpm it'll just drop the revs when you put load onto it. It'll usually happen for maybe 10-15secs, but today was happening for a minute or 2, drive normal then happen again for a minute or so.

I tried to read the fault codes, but I just get the engine light flashing but in no pattern, it just stays the same. I bridged Te1 and E1, I have heard VVT cars you bridge different pins, but I haven't seen anything on it?

The only thing I can think of is something to do with the ETCS? It's really giving me the shits now...


Also it'll ocasionally stall or the idle will be lower than normal, or higher than normal, if I turn AC on it'll usually make the idle normal after I turn it off, not sure if this is related.



cheers
Stu

[JP]

possibly an issue with the coil packs, have you had a look at the loom near the ECU to see if it has been molested in Japan?

[S_E]

I've pulled the ECU out and cleaned the connections, didn't see any hacked up wiring, also have cleaned (sprayed electrical contact cleaner) on just about every connection I could find in the engine bay. The only thing like that may be the alarm? when it arms itself it won't go off if you open the doors, but it will after a couple of seconds of ignition on, if you turn ignition on most of the idiot lights will come on, except the ETCS SNOW light, that only comes on after you disarm the alarm, so maybe the alarm wiring is near some ETCS wiring, but I doubt it. It does kinda feel as if the ETCS butterfly is closed when the problem occurs though.


Will check resistance of the leads, have heard of coilpacks creating weird problems on the VVTs, cheers

[The Real Roadrunner]

are they fly by wire? if there not just disconnect the plug for the etcs motor and it shouldnt allow it to close.

cheers
linden

[S_E]

Yeh ETCS is fly by, and a normal cable throttle after it. I have unplugged it before, and it seems to run fine, but it doesn't fix whatever the cause is, and the ETCS SNOW and TRC OFF lights flash.

Am getting a PFC in a few months, so that should eliminate an ECU issue, and if it doesn't, it should show me some data that might help..