KZJ78 Engine cuts out

[robthebox]

Hope someone can help.
Driving normally and the engine cuts out , today I noticed that the heater plugs light came on at the same time as the engine cut out.
I try to start it.. but while the heater plug light is on it doesn't fire. Then the light goes off and were away again. Seems to happen when my foot is off the gas' slowing up for lights etc. Ben kindly gave me a load of pointers (thanks Ben) but as yet I have not been anywhere close to finding a way past this. Hope that the new info (the light) is helpful.

The fuel filter was changed just under 2000 miles ago, also I have checked there is no vacuum in the tank when it cuts out.
The heater plug light makes me think this is electrical and I know little of the dark arts involving ecu's and electrical faults.
Finally I should point out that this started the week before Lincomb and has got steadily worse from once a week to 5 times a day. I have been lucky and avoided the embarrassing trip home so far but after today, I wont go out in it till its fixed.

So over to the thinking caps of the mighty forum.
Rob

 

[Peter Barry]

Hi Guys,
I have a 70 series which is stalling, it's a turbo diesel 2.4ltr
It starts like clockwork, runs well, but goes knocky and stalls after 5 mins each time....only driving for a couple of miles and stalls over and over.

 

[Peter Barry]

anyone has a wink of an idea what this could be ? Your help/assistance is appreciated !

 

[roscoFJ73]

anyone has a wink of an idea what this could be ? Your help/assistance is appreciated !

It is most likely air getting into the fuel lines or something blocking the fuel. I think the best way is to isolate the problem by rigging a temporary fuel supply in the engine bay. Get a small plastic container near the fuel pump at about the same height with a rag shoved in it to stop fuel splashing out.
If the problem is still there ,you know its in the fuel injection pump ,if it goes away you know its further downstream.

A common problem in areas where it's damp most of the time is that the fuel pick up on top of the tank rusts away letting air in. I have never seen it happen in Australia ,but its quite common in the Canada and the UK.

 

[Peter Barry]

Hi Rosco,
Thanks for that, so I should eliminate the thought of any faulty-sensors shutting down the fuel-line supply if any are in fact fitted at-all ?

 

[StarCruiser]

Sensors? Not sure they were thought of when that truck was born. [emoji6]

 

[StarCruiser]

Possibly water contamination though the filter should separate it out. Try draining a little out the bottom of the fuel filter to see if it's diesel or water then diesel.

 

[Shayne]

Quick google suggests a faulty fuel cut off solenoid is quite common .

 

[Peter Barry]

Well the fact that the model has air-conditioning and electric mirrors, I thought that it might have sensors to stall the engine if the temperature sensors or similar sensors fail, as a precaution against further engine damage, maybe I'm thinking too much.

 

[Peter Barry]

ok, where would the cut-out solenoid be found ?
thanks shayne

 

[Shayne]

Dunno i found this which i didn't read but might help ? http://forum.ih8mud.com/threads/kzj78-starting-problem.399117/ . I don't know your engine but to me the pic in the link marked fuel cut off solenoid looks very like the spill control valve on my 1kz-te electronic pump , is yours an electric pump ?

 

[Shayne]

If it is an electric pump https://www.youtube.com/watch?v=Xzws_H9z5Zg

 

[Peter Barry]

 

[Peter Barry]

This is the Model I got, i'll try the temporary fuel source and also will check the solenoid....

 

[robthebox]

I'll be doing the same.

 

[robthebox]

The fuel pump is chugging away and I reckon the shut off solenoid is dodgy ..... I've cleaned the plug but the fault is still there. has anyone removed the solenoid or got any pics of it before I go in blind ... any advice would be most welcome ......

 

[Beau]

The fuel pump is chugging away and I reckon the shut off solenoid is dodgy ..... I've cleaned the plug but the fault is still there. has anyone removed the solenoid or got any pics of it before I go in blind ... any advice would be most welcome ......

I've removed mine before. Sadly no pictures. From memory I think it's a 32mm spanner you'll need. A thin one works well. I cut mine in half as there's not a lot of space. Oil filter will also need to be removed. It's tight but once you crack it loose you'll be fine. Be careful with it, as it's delicate. Once removed you can actually separate the bottom by prying the tabs open at the side. Then the plunger piece can come out. Whilst you have it removed, clean the triple layer filter that's underneath it. The 3 filter layers are in one metal piece which can be removed. Use something thin to separate the top metal insert and then the filters will come right out. The hardest bit is removing it.

 

[robthebox]

NZ has a 4x4 forum (offroadexpress.kiwi) a couple of guys with prado KZJ78's have had the same probs and ended up having the ecu's repaired and it seems to have sorted it out.
I have cleaned the vacuum pipe from the manifold to the map sensor above the injector pump plus cleaned every plug in sight. Test run to the garage to fill up and it died at 60mph just as I had reached the point of taking my foot off the gas.
I'm looking for an ecu guru now......

 

[Beau]

NZ has a 4x4 forum (offroadexpress.kiwi) a couple of guys with prado KZJ78's have had the same probs and ended up having the ecu's repaired and it seems to have sorted it out.
I have cleaned the vacuum pipe from the manifold to the map sensor above the injector pump plus cleaned every plug in sight. Test run to the garage to fill up and it died at 60mph just as I had reached the point of taking my foot off the gas.
I'm looking for an ecu guru now......

I experienced the same symptom. It was in my case the spill control valve.

 

[robthebox]

The cause seems to be oil in the inlet manifold air map sensor. I drained the pipe and cleaned the plastic baffle out ( it's clipped to the intake manifold) washed out the pipes with WD40 .... Then go for a run. Mine was sorted, twice sadly after a 200 mile trip in wales it did it again, a clean once more and it's fine again.
The cause of this is a worry though, seems that high crankcase pressure is the culprit. Compression test next .. ugh. I'm not happy.
hope this helps though.