strange and baffled

[shiny]

Hi Shiny here
I have encountered a series of problems that have baffled me

Number one problem
If the truck it’s a Hilux 2.4 turbo diesel 1990
falls below 1500 revs it cuts out I have to have the hand throttle
screwed up to these revs if I cut it to below say 1000 revs it cuts out totally
I replaced air filter but it made no difference
I can see no hoses broken or leaking, I was running it on veggie oil for a while
But as it smoked one day I cleared the jets with redex in tank and reverted back to Pure diesel, the engine runs sweet and does not labour.. if it idles and I turn the Revs down to 1000 there seems to be a click (this may be my imagination as engine is switching off) help would be appreciated as you can imagine in this hot weather in a traffic jam on high revs it is no fun.

Problem no two
For some reason and I am not sure if the above is connected to this because it happened around the same time
My heater fan won’t even operate..So air con won’t work. The light on dashboard wont Light up, nothing happens and I have checked all the fuses
Took truck over to Tony at Basingstoke and we replaced the relays behind glove Compartment but still nothing, I am a bit baffled by this..am I missing something!!

Help would be much appreciated

Shiny

[BUSHWHACKER]

Prob no. 1 Sounds like the TPS (throttle position sensor)

Prob no. 2 If you look up behind the glovebox, you should be able to see a couple of fuses, it could be one of theses that has blown.

[Vagrant No2]

2 faults at same time sound related . Maybe a voltage problem . If the voltage is low at the fuel shut off switch it will shut down and cut the engine . If the heater fan has packed up at same time then it could be related . The fuse or a connector is bad or broken that feeds power to both the heater and fuel pump ? . May be worth checking the voltage at fuel shut off switch on pump and then trace the feed to heater for a starting point .

[shiny]

thanks bushwhacker

Prob no. 1 Sounds like the TPS (throttle position sensor)

Thanks Bushwhacker I have checked those fuses behind the glove box and they all look oK...what is a throttle position senser? T P S and where can I find it??

Prob no. 2 If you look up behind the glovebox, you should be able to see a couple of fuses, it could be one of theses that has blown.

Thanks Bushwhacker I have checked those fuses behind the glove box and they all look oK...what is a throttle position senser? T P S and where can I find it??

[shiny]

2 faults at same time sound related . Maybe a voltage problem . If the voltage is low at the fuel shut off switch it will shut down and cut the engine . If the heater fan has packed up at same time then it could be related . The fuse or a connector is bad or broken that feeds power to both the heater and fuel pump ? . May be worth checking the voltage at fuel shut off switch on pump and then trace the feed to heater for a starting point .

Thanks Vagrant I will search out this possibility
where can I find the Fuel Shut of switch?

Thanks Shiny

[Vagrant No2]

Thanks Vagrant I will search out this possibility
where can I find the Fuel Shut of switch?

Thanks Shiny

Should be located on the pump itself . As I dont have a diesel I can not tell you exactly where it is on yours .

[shiny]

Jet maybe?

This problem I have of having the revs high 2000 otherwise truck cuts out I thought it was electrical but now I don't think so...I think its a blocked jet..got into truck this morning and it started to labour and smoke..I put some Millers Power pluss to give jets a clean, Boy the smoke ..the village nearly got up a lynching party, maybe its me but I was sold millers power+ in shop instead of redex..maybe redex is better?

anyway now it seems the revs have to go higher up to 2500 or else it fades and the truck is ok while its accelerating, but as soon as i release gas it labours and smokes, but at 2500 it seems to hold...is there a mixture control on my surf 2.4 turbo diesel 1990? do jets get worn out?, if so are they easy to replace? ...so many questions..would appreciate help as going on holiday soon with Kids

Thanks Shiny

[Rob]

Shiny, you said the air filter has been changed but when was the last time the fuel filter was replaced? I've also read that veg oil can loosen deposits in the fuel tank the first time you use it, resulting in the fuel filter getting clogged very quickly...just a thought

[TonyN]

Hi mate, just got your message on the phone.

Lots of good ideas in this thread already.

Also look at the top of the fuel pump, there is a black unit with wires going into it, this is the non-efi version of the throttle position sensor, check this isn't loose.

Also check the hoses to the altitude gadget, its right next to the TPS above.

Hard to believe its related to the heater control, but it did happen at a similar time. Also if it helps other, when we tested the air con clutch by directly linking it to the battery, the clutch engaged and then the whole motor shut down as if turned off. Now there is a idle up device to raise the revs when the air con is on, maybe this is misbehaving, its the soloniod on the drivers side inner wing, near the fuse box. Check the vacuum hoses and connections to this as well.

Maybe pull the heater motor fuses, incase there is a short in the motor or wiring.

Clogging of something in the pump due to the redex loosening junk in the tank may also be an issue, but the filter should have caught it. But thats harder work and probably more money to fix so start with the easier stuff first.

[MattF]

Thanks Bushwhacker I have checked those fuses behind the glove box and they all look oK...what is a throttle position senser? T P S and where can I find it??

If you have only visually inspected the fuses, it would be
worthwhile checking them again with a meter. O/C fuses
can be deceptive. A lot of the time, they can blow without
it being easily visible.

[shiny]

Shiny, you said the air filter has been changed but when was the last time the fuel filter was replaced? I've also read that veg oil can loosen deposits in the fuel tank the first time you use it, resulting in the fuel filter getting clogged very quickly...just a thought

thanks rob yes I have put a new fuel filter in from Toyota thought it would make a difference but it didnt but thanks yes I did
Shiny

[shiny]

thanks Tony will try suggestions

Hi mate, just got your message on the phone.

Lots of good ideas in this thread already.

Also look at the top of the fuel pump, there is a black unit with wires going into it, this is the non-efi version of the throttle position sensor, check this isn't loose.

Also check the hoses to the altitude gadget, its right next to the TPS above.

Hard to believe its related to the heater control, but it did happen at a similar time. Also if it helps other, when we tested the air con clutch by directly linking it to the battery, the clutch engaged and then the whole motor shut down as if turned off. Now there is a idle up device to raise the revs when the air con is on, maybe this is misbehaving, its the soloniod on the drivers side inner wing, near the fuse box. Check the vacuum hoses and connections to this as well.

Maybe pull the heater motor fuses, incase there is a short in the motor or wiring.

Clogging of something in the pump due to the redex loosening junk in the tank may also be an issue, but the filter should have caught it. But thats harder work and probably more money to fix so start with the easier stuff first.

Thanks Tony whats a TPS??? I have put a new fuel filter in..
I am going out tonight and I will give it some pedal to the metal
I have also just been puting in pure diesel until i sort this out..
I have to ..I gota tow a caravan soon..

[shiny]

no joy

Hi everybody today I have had no joy in sorting out my high rev problem its so odd it runs ok at 2500 rpm but as soon as i take it back a tad on the hand throttle it cuts out.
I have been to a couple of garages and some have suggested fuel pump switch, or possible a recon fuel pump which would be £800 reconditioned.
some have suggested fuel timer need adjusting. or fual swith gone don't know what to think at least its running.. but at those revs its expensive and i guess I could burn the clutch out??..Tonys from Basingstoke is getting married anyday now so he will be busy. I have to pick my kids up at end of this month at Stanstead for there stay with me..I just feel dumfounded.. i took the fuses out of aircon and checked a few other suggestions from Tony..even gave engine a good gunk and wash, as some leads were oily..but no difference started on the button, but if i undo hand throttle to cut revs it stops...any more ideas?

Ive got it but i don't need it at this moment...Shiny/Dull

[DaveD]

I hope you get this one fixed soon, its a PITA when you cant narrow down what the heck is going wrong in the first place. Took me ages after following advice from several garages to discover that it was what I thought in the first place...CHG

Reading through it seems as if you are getting fuel delivery but either not at the right time or not being compressed enough. Does the truck start ok?
Any obvious origin for the oil on the leads you mentioned?

Not much help but I cant think of much else other than what has already been covered.

[shiny]

thanks

The oil on leads was from me putting fuel cleaner in the two hoses that go into fuel filter I undid them and poured it straight into them and in doing so spilt some on leads so decided to gunk it in case dirty oily leads were a problem..boy that fuel cleaner smells grim...have you noticed also that whenever you want to burn some carbon off and clean fuel injectors there is always some tractor that pull out in front...and when its sluggish and smoking there is always a performance car up you tail looking $$$$ed off.

Oh well in a previous life I must have been Gods mechanic and $$$$ed him off
No trouble starting..this is driving me nuts..

Shiny