Jzx100 VVTI 1JZ starting/Idle issues

[Toon]

It flashed constantly at a high rate with the terminals bridge so it appears that there are no codes.

Thanks for the info.

Will give the AFM thing a go.

Could a faulty ISCV cause these symptoms?

what exactly happened when you bridged the terminals? No error codes would make the warning light constantly flash at high rate.
Coil bottom rubber seals can fade over time, also coil's case may contain small cracks, sometimes barely visible but enough to lose voltage before it gets to the plug
vvti cam gear is big stuff driven by timing belt. It has two rubber seals which can develop leaks, and it can also seize

AFM: disconnect battery, disconnect AFM, try to start. Should run ok at low rpm without AFM

[George]

Can be potentially, but last time I personally seen toyota engine with iscv was about 3-4 years ago. Those with etcs-i have no such problem, it either works or not

[Toon]

I just tested the ISCV as per these instructions- http://www.cygnusx1.net/Supra/Librar...spx?S=FI&P=107

It is showing the resistance at around 45. It says that it should be between 10-30ohms in that manual... Is this going to be an issue, as in the manual it says that if it isn't between those values then replace the valve. I then did the second test and it opens and closes the valve as it should, does this mean it's ok?

[George]

should not be an issue as long as both the valve itself and what's behind it are clean
Back in the days I was working with these older engines the two main issues were carbon buildup and improper wiring of master efi relay

[Toon]

Hmm any other ideas? Not worth just trying another iscv just in case?

[George]

that's always a good option if you have access to another iscv

[Toon]

Fully closed the iscv manually using the testing method and then connected it up to the plug. When I turn the ignition on/off I hear some clicking at the iscv, but upon inspection it has not moved to the open position.

It looks like the iscv is either stuffed or it isn't getting the correct signal.

[George]

more likely to be stuck than something else, but it's worth checking ECU earths (ignition on, ECU connected , measure voltage between battery negative and each earth of ecu, anything above 0.5v is bad)

[Toon]

Thanks for your help mate will check it out

[Toon]

Swapped out the iscv and it seemed to be ok for a short while....drove to shops and when I went to start it it revved to around 2k! Drove it home and it was idling around 800rpm. Started it up before and it just wants to stall. Seems like it has just shut off the iscv valve.

I tested the ecu grounds and they all tested ok. Also tested continuity to the iscv pins from the ecu to the plug and they seemed ok too.

Any other ideas? What other sensors does the ecu use to tell the iscv to open? Tps?

[Toon]

I used the 2j spec sheet to test the TPS. E2 to VTA1 was within spec but the IDL to E2 was showing 3k ohm closed throttle.

Does this indicate a faulty TPS as it says it should be .5k ohm when closed? Don't want to buy something else that it isn't!

[George]

You should test the IDL/E2 resistance with battery disconnected and ECU disconnected

[Toon]

That is testing with the throttle body off the car nothing connected

[Toon]

TPS definitely looks to be stuffed. It's resistance is going down when it is opened.

Back probed the TPS with it connected and ignition on. E2 to IDL is showing 5v on closed then decreases from there when opened.

[George]

Check that there's always zero volts at TPS's earth terminal (with TPS connected)
If so and the above is still observed then it's surely stuffed