1HDFT glow system

[nielsc]

Hi all,

I have a '95 HDJ80 with 1HDFT engine.
Ever since I have bought it it does not seem the glow when starting, the glow light does never come on when I switch on the car.
I have checked the relay under the RHD battery and it seems OK. The connection wich is always +12 did get a bit hot as the plastic cover is a bit burnt.
I checked the relay coil for continueity and it should be good. Offcourse it still can be broken but I can't tell without replacing.
Also no 12v while switching on the ignition at the glow screen. The glow screen also has continueity.

The odd thing is, when I come to a very hard stop the glow light lights up on the dashboard !!! Sometimes it lights up while a driving but this was only like 3 times or so.
Sometimes while driving up or down a very steep climb off road it also lights up.
Very confusing !!!

Anyone have any more experience with the glow system on a 1HDFT ?

Thanks !

 

[Towpack]

Someone has mentioned on here (can't remember who) that the intake heater relay on the 1HD-FT was the subject of a Toyota recall many years ago. I had a problem with my pre heat not working which turned out to be the relay. In fact is was causing a permanent battery drain of around 1/2 Amp due to burnt/corroded contacts. .....I replaced it with a motorcycle starter relay around the same size for a fraction of the price of an OEM relay.
I wired a switch under the dash so I can turn the heater on/off manually.
Not really sure why the glow light should come on under heavy braking though!

 

[StarCruiser]

Sounds like something is moving and touching a wire down somewhere that's perhaps rubbed through or become loose somewhere. It maybe where the contact has burned and a smaller control wire is floating about. Warrants further investigation especially as you say it has burned. This can cause conductive tracks that can draw current like Towpack has described.

 

[nielsc]

Yeah I have been trying to find anything that is wrong or loose or could move while braking hard but could not find anything.
I saw the thread that you or someone replaced the relay with a small starter relay. I've been thinking to just replace it and see from there, but I think IF contacts in the relay are loose and make contact while braking it would still not make the glow light light up?
BUT, my relay is burn the same way like the one in the photo, slightly less hard tough, but also the left connection. Maybe replace I should replace that first anyway

 

[Grimbo]

First job as you say would be replace the relay , the grid heater is controlled by an ECU I think so it will only be active below certain temperature , it will also continue to glow after the engine is running to help with emissions.
The best option unless you are expecting very cold weather is just to insulate the wires and leave disconnected .
My 1HDFT starts with no problem at -15 with the engine firing after less than 1 revolution .

 

[nielsc]

First job as you say would be replace the relay , the grid heater is controlled by an ECU I think so it will only be active below certain temperature , it will also continue to glow after the engine is running to help with emissions.
The best option unless you are expecting very cold weather is just to insulate the wires and leave disconnected .
My 1HDFT starts with no problem at -15 with the engine firing after less than 1 revolution .

I have been thinking this aswell. It starts fine in cold weather indeed, but idle is 400 -500 RPM unless i give it a bit of (hand)throttle when starting with freezing weather and lots of smoke for the first minute. I was hoping this would get a bit better if it would preheat.

 

[Grimbo]

That sounds about normal ,
Yes getting the grid heater working will solve both the low idle and the smoke which is incomplete combustion of the diesel .
How many Kilometres has the engine done ? it could be worth getting the injectors checked but if after a few minutes it runs clean then probably not worth it .

 

[nielsc]

It has 208,000km so not a lot. Offcourse with these old cars you can never be sure if they are the real km's. But yes after a minute the smoke is gone and only when the engine is cold after a night outside.

 

[Towpack]

The engine should idle much higher than this from cold wether the heater is working or not due to the ACSD (the spring loaded/thermo wax plunger mechanism) linked to the throttle on the side of the pump. Assuming the ACSD is fitted then it must need adjustment. The operation of the heater has no effect on idle speed. I know because I removed the ACSD mech on mine due to a leaking O ring and never refitted it once I'd repaired it. I just use the heater and increase the idle for the first few minutes with the hand throttle. The ACSD also advances the pump timing slightly when cold but the engine still fires on the first 1/2 turn without this.
This is the ACSD mech..The 2 hose connections on the right carry engine coolant to the thermo wax servo.

 

[nielsc]

I have to take a look but I think the ACSD isnt fitted anymore. My 80 has been converted to an A442f autobox with all genuine parts from the jdm spec 80s and I think the mecanism is replaced with a lever for the kickdown cable.

 

[StarCruiser]

Shouldn't be Neil, mine has it and is a JDM auto. The ACSD sits blow that quadrant for the kickdown.

 

[nielsc]

I have checked and I can confirm this device is fitted. However, the little tab that hooks behind the lever on the pump was pointing downwards so the ACSD couldn,t work. I hooked it behind the lever again and we'll see when the engine is cold again if it works or not.

Edit:

I just started it when cold and watched the ACSD while the missus started and i did not see it move the lever. Lots of rattling and dieselknock with the low idle

 

[Towpack]

You'll not see the ACSD move at all when starting. It moves gradually as the coolant heats up/cools down, opening the throttle linkage and advancing the pump timing at the same time when cold. If you look at the ACSD pic above you'll se a lever at the bottom with a black plastic roller on it. This is what acts on the throttle linkage opening it slightly.

 

[nielsc]

Oops, then I think I was looking at the airconditioning idle up actuator.
I've been reading on ih8mud and i've read they often rattle inside the pump, well I find my pump to be rattling pretty hard. This is maybe why my 80 has a low idle and rattles because the acsd is not working?

 

[Towpack]

AFAIK the issue with the ACSD 'rattle' is brought about by the unit being out of adjustment and not fully disengaging with the timing mechanism in the pump when at full operating temp. The pin on the rear of the ACSD then wears and has been known to be break off and fall into the pump with the ensuing problems that could cause. I have an intermittent 'tick' on my engine somewhere that's been there for the last 60k miles. When I removed the ACSD to fix the diesel leak I was curious to see if this was the culprit but it was not. The timing pin showed no signs of wear at all.

There are vacuum operated actuators on the pump for air con and power steering but are completely seperate to the ACSD

 

[nielsc]

Thanks! I'll have a look in my manual and see if it can be adjusted.

 

[nielsc]

So I found out that the thermowax mechanism is attached to the pump, but the lever is gone and a blanking plate has been fitted to the pump, so that explains a lot

 

[Towpack]

That's what I did when I removed the ACSD to repair it except I just linked the coolant hoses with a piece of alloy tube and removed the whole mechanism as one unit.
So you'll just have to advance the idle with the hand throttle as I do at present, until such time as I decide/can be bothered to refit it!

 

[StarCruiser]

So I found out that the thermowax mechanism is attached to the pump, but the lever is gone and a blanking plate has been fitted to the pump, so that explains a lot

Can you upload a photo Niels? Might be worth us looking too if you don't mind.

 

[nielsc]

Can you upload a photo Niels? Might be worth us looking too if you don't mind.

I'll make a pic this week