ae101 4agze headrecker

[speed1ton]

Problems
1: Normal operating wramed up cruising tempeture, the temeture gauge will read 1/4,
Will idle at 1500rpm and jump a little up and down if lights and aircon are switched on.

2: If let sit in traffic and roast the fan will kick in when the temp gauge is at half way and idles at the correct 800-900 rpm

This will all go back to the number 1 stats listed above when cruising again.

Heavy fuel consumption aswell only 400k or 250 miles on a full tank.

[TERRA Operative]

Dude, my AE101 4AGZE Levin only gets between 350 and 400Kms a tank.

Clean your idle control motor (on the side of the throttle body) with carby cleaner. You can even open it up to an extent to get right in if you're keen. Make sure you have some gasket goo though for when you put it back together.
Then reset the idle speed, to the correct value.

A dirty sticking idle speed control is common for most 4AG engines. They need perodic cleaning.

[speed1ton]

I'ts a thirsty beast for a small engine. 400k if Im a very good boy

From reading on here I've seen it's a common problem so I've the gaskets orderd, there not too dear so I'm going to crack her open.

Is the temeture gauge as I described a syntom of a dirty ISCV or is that a seperate issue do you think.

[timbosaurus]

Has the thermostat been pulled out by any chance?

That could stop it reaching normal temp under cruising. I'm not sure if the GZE's idle up if they think they're cold.

[timbosaurus]

Nah, I don't see how the ISCV can affect temp guage.

[speed1ton]

Has the thermostat been pulled out by any chance?

That could stop it reaching normal temp under cruising. I'm not sure if the GZE's idle up if they think they're cold.

I nocticed the problem when I bought her and I replaced it with a genuine thermostat with no effect.
There was no change from replacing it.

[speed1ton]

Nah, I don't see how the ISCV can affect temp guage.

Mmmmmmm might be a seperate issue so

[timbosaurus]

I'm sorry i cant help then.

Sounds like the fans are doing the right thing (switching on just over half), the temp gauge is doing the right thing (tracking the engine temp), and I'm not sure about the GZE's, but some cars idle high until warm so the ECU could be operating properly. If the thermostat is working correctly then I'm not sure why you wouldn't be running at approx half on the gauge.

I'm sure you flushed the system clean when you changed thermostat, but even so a clogged passage wouldn't keep the temps down.

[TERRA Operative]

ISCV will affect the idle bumping around the place and sitting high..

Also, make sure the cooling system is bled correctly. The 4AGE's have a problem where if there is any air in the cooling system, it will collect at a point where a temp sensor sits and cause similar symptoms as you describe.

[speed1ton]

Coolant was changed but not by me, i'll make sure tis bleed and run a diagnostic to see if it might be senors etc.