1KZ-TE Fuel Starvation / Spill Control Valve

[Shayne]

I'd be looking behind the steering wheel for a chaffed wire .

 

[MSJW]

Hi guys, small update.

I’ve spent some hours looking at the wiring below the steering column and can’t find any wires or relays which look damaged. There are the odd wires which have been spliced together and taped over to fit new connectors etc, however upon starting the vehicle and wiggling these specific bits, nothing happened.

For some context I had the car running for probably an hour on and off while I was doing these checks. Unfortunately I couldn’t find anything that would make the engine cut out, despite wiggling individual wires and entire looms.

I checked the electronic ignition switch/ barrel which cycles the car between off, radio on and engine running and it seems to have a distinct click between each setting. I’ve attached a pic of this part. Does anyone know where new ones can be sourced?

The car was static while running (not being driven and rocking about) so it makes me think something must be lose or susceptible to movement making it cut out. Each time the car has cut out it’s during transit.

I’ve got a couple of extra questions:

On the attached pic of a 2.4 fuel pump, is the thick wire
in relation to fuel cut off? Could it be that either this wire is worn - or something in the pump which gets triggered when moving?

Is it sounding more like the ECU could be the issue? I was unable to find it however looking at a Prado diagram it looks like this is inside the dash on the passengers side (hassle to get to!). Has anyone on here with a granvia accesses the ECU before?

Thanks as always chaps

 

[StarCruiser]

If there is a separate fuel cut off solenoid then identify it, be ready with a test meter and when the engine dies do nothing but separate the connector for the shut off. Then test on ohms across the solenoid contacts and you should get a lowish number reading. Then test on Volts on the loom side connector and you should get 12v to 14.4v or thereabouts. Anything different should show which way to look.

Not all stops were while in transit. You said you shut the door the other day just after it was started and it cut out. Keep the faith and keep searching.

 

[MSJW]

Me again. I took out the ECU today (passengers side about a foot under the air bag unit, for anyone stuck in the future).

All of the connections look fine. No burn marks. I opened up the unit and there is a diode(?) which has sicked out something. Could this be causing the issue?

Any recommendations for ECU specialists who are in the know on 90s japenese electrics?

Im praying this is the cause!

 

[StarCruiser]

That’s a capacitor. It’s clearly not well. Replacement with the same value and type, round the same way by anyone who knows their way round a circuit board and soldering iron and is reasonably competent should answer your question. Not sure if this is one of ‘the capacitors’ I’ve read about that go but it’s certainly in need of replacement. You don’t need anyone specialist in 90s anything, just someone competent.

 

[MSJW]

That’s a capacitor. It’s clearly not well. Replacement with the same value and type, round the same way by anyone who knows their way round a circuit board and soldering iron and is reasonably competent should answer your question. Not sure if this is one of ‘the capacitors’ I’ve read about that go but it’s certainly in need of replacement. You don’t need anyone specialist in 90s anything, just someone competent.

Thanks, I ask as I called one ECU company earlier and they said they weren’t sure if they could test this ECU as they have little information on it and couldn’t troubleshoot a similar one which was sent in earlier this year

 

[StarCruiser]

Yes, that can be the case, however I was referring to the repair yours is showing you it needs. It’s not always the case that you get such an obviously damaged component but one such as that is a gift. Capacitors do age and having all of them replaced (with ones of the same value but a higher voltage rating) is not a bad idea. If it still gives trouble then having it tested is essential. It does need to be repaired correctly but it’s not essential to have it repaired by an ECU specialist.

 

[Beau]

Looks like it might be the ECU. That other valve on the pump is for adjusting the timing of the fuel. You can test all sensors out on the pump to see if they are within spec, but in terms of drivability the spill control and RPM sensor on the pump are the most important.

 

[MSJW]

As an update, I called around three ECU repair companies. Two of them didn’t have any successful experience with a 1KZ ECU and so I called the ECU Doctor and had a reassuring conversation with a chap who said he was familiar with this item and could test the unit and try to repair and return it before the Christmas post cut off. I sent the unit off on Friday and yesterday had a call saying two faults were found (great service from the ECU Doctor who also give a 12 month warranty). One fault was in relation to fuel injection, which was a relief to hear given it seemed as if the fuel feed was being cut off to the engine causing the car to shut down.

I refitted the unit today (great service) and fitted it back on the Granvia. Last week I had to jump start the car however today it started first time. I drove the car for a few miles and it didn’t cut out which is a good sign.

I’ll do a proper run with it tomorrow and hopefully won’t be stuck on the side of the road again. Cheers for all the advice guys

 

[StarCruiser]

Sweet and thanks for posting the update. I too had good service from the ECU Doctor.

 

[MSJW]

Thanks for the recommendation!

Also for anyone replacing the SPV in the future I read that a thin 32mm spanner was needed. You can buy a viscous fan spanner however it’ll need cutting down. See the pic below which shows how much needs to be ground off with an angle grinder.

On the Granvia you need to remove the battery, unplug various wiring looms and cable tie them out the way. You’ll also need to remove the oil filter in order to get the angle on the valve/ pump. Pretty fiddly but doable without needing to remove the pump altogether.

 

[nautilus]

Hi all, I'm new here (I have a 94 Hiace SC with the 1KZTe engine) and am having similar issues as the OP had except it doesn't always cut out immediately. Sometimes the engine catches itself before it cuts out. There is no check engine light or any codes to read off the OBD.

Some notes from various tests:
- turns over easily and starts right up
- runs from 30 seconds to 10 minutes before it fails
- briefly partially-opened up 1st injector valve while vehicle was running and fuel came out
- checked tightness on other injectors except for 4th (rear) as it'd tricky to reach
- replaced fuel filter and primed it. Started right up and ran about 3-4 minutes.
- fuel temperature sensor leaks a bit after priming.
- The first time it failed I had replaced the battery earlier in the day.
- tach at idle is usually steady, there was one test where while holding at 1600 RPM got a sputtering effect instead of abrupt fail where the tach dropped off when it spluttered. Seemed to try to “catch itself” in effect.
- tried to isolate whether it was air getting in the system and the sensors were correct in shutting it off or there was an incorrect signal but was unable to disconnect spill valve without it turning off

Interested to hear any thoughts on these symptoms. It seems like the three prevailing hypotheses are that 1) the ECU has some issues or 2) that the spill control valve filters need to be cleaned or 3) air is getting back into the system.

 

[Beau]

The tach dying would indicate the RPM sensor (the white plug on top of the pump) is losing a signal and therefore the engine thinks it's not running thus turning it off. I'd check the wires on this. You can also check the resistance of just about all the sensors including the SCV and see if they are within spec.

 

[nautilus]

To clarify, the tach only died during that one test. For all of the other cases, it died abruptly and so it was hard to gauge whether the tach issue was leading.

Here's what I've measured so far. Not sure if there is a sensor that I should read that I haven't?
SCV: 1.8 Ohms (w/in spec)
engine speed sensor: 224 Ohms (just w/in spec)
turbo sensor pressure: 4.92 V (w/in spec)

Other notes:
Alternator seems okay to me- disconnected the battery while running and it stays running. Reads about 13.75V.
From quick visual/touch inspection, belts seem to have reasonable tension/are in good shape.
I bought this HiAce about two months ago and it's only been driving for about 1 month regularly, ~1500km. Prior to this, I'm not sure how long it was sitting for.

Thanks!

 

[Beau]

Check the valve towards the bottom rear of the pump. That is needed to start too. I believe it adjusts fuel pressure. If the RPM sensor fails, it will want to cut the engine. I've had some spill control sensors read within spec but still be bad. There are also filters in the pump. One under the SCV, one behind the temp sensor and some pumps have a cylindrical filter on the inlet of the feed.

 

[GreatScot]

@MSJW @StarCruiser which ECU doctor did you use that you would recommend? There appears to be one one in Widnes and one in Plymouth with very similar names.

Thanks in advance

 

[StarCruiser]

It was ECU Doctor (not Doctors) in Plymouth that I used.

 

[GreatScot]

@StarCruiser cheers, that's where I've sent it.