cranking but not starting. Help me diagnose

[mhhs]

Hi Guys,

I need your assistance in diagnosing and finding out why my car does not start. In short, it is cranking but not even trying to start.

First, some background information.

I bought it about 2 years ago and at that time it had been standing for more than 5 years after the previous owner and local Toyota dealer workshop gave up trying to fix an intermittent starting issue.
It is a HDJ100, manual, just over 600.000 km but in fairly good condition except from that it does not start.

After a thorough cleaning and started looking in to the problem I noticed that the EDU attachment bolts were loose. Previous owner had mounted the winch relay box in the same area using longer bolts. New bolts and the car started right away. Success, or was it just the intermittent character of the problem?
I started to fix other problems from the vehicle standing still for a long time. Brakes were seized and brake booster buzzer beeped annoyingly. I tore apart the brake booster assembly and managed to fix the electrical motor.
Now life came in between and the car was standing for a long time again, could only work on it every now and then. But everytime I tried it still started easily.
Next step was to fix the clutch since the pedal often stayed down after pressing it. Fluid was more of a paste, and when that was cleaned out and filled with new fluid the clutch worked fine again.
Time for first test drive! But, now it is not starting anymore. Strange, since I have not done anything to the engine while fixing the clutch. Probably totally unrelated, but still..
It is cranking, but I do not think it is getting any fuel. It does not smell diesel. It does not even coff.
Decided to start over and be more thorough.
1. drained the fuel tank. Changed the pickup filter and refilled with new diesel.
2. new fuel and air filter. Primed with the manual pump and diesel is getting through.
3. removed the engine tuning box and replaced the complete engine loom from ECU and forward since previous loom had several splices after workshop did their diagnosing.
4. removed junction box in the left a-pillar (this was a pain) and checked spill valve relay. Junction box ground points were quite corroded. Cleaned all contacts and replaced all fuses. Now dashboard, especially fuel gauge works better and stopped flickering.
It still does not start

Found information on the internet, that there is a relay for the immobiliser that is sensitive to voltage drop. Tried bypassing without success. Immobiliser indicator on dashboard is blinking and stops when the key is inserted. Is this enough to draw the conclusion that the immobiliser is working as it should?

Found the lc100 online manual and started to follow diagnosting schemes.
Measured all the things on the fuel pump and cannot find anything wrong. I have been told that the fuelpump was replaced by the Toyota dealer which was very expensive but I have no documentation and previous owner is not avaliable any more.
From DI-71 (EDU circuit malfunction) I can measure ~12v at pin2 on EDU connector and about 1.5 ohm between 4 and 5.
Measuing at the ECU, SPVD is about 0 volt. For SPVF i measure 5V which seems odd, since the manual says 9-14V. BUT diagram on page DI-71 shows 5V? Is this a problem and if so, what does that indicate?

I am starting to run out of ideas and therefore post here. I am fairly certain it is electrical, since it was running fine for a while since I bought it. Or what do you guys think? But I do not know how to proceed and find out what is wrong. Could be something silly small or really advanced, I am not a mechanic and could easily have missed something very basic.

Ideas?

Thank you for taking your time to read this overly long post!

 

[Shayne]

Hole in fuel line sucking air allowing fuel to run back to the tank . When the leak is in the filter primer assembly its almost impossible to know .

Will it start if you connect a bottle of fuel direct to the pump ?

 

[mhhs]

oh, no I have not tried that. I thought that it would at least fire up a little if I was pumping the primer while cranking. The button feels a little bit dodgy, I can pump up so it gets firm but then if I wait a short while I can pump again. I also have a feeling that, when firm, I can push harder, push through, and then it is possible to pump again. I thought this was because of air in the system after replacing filter and fuel in the tank. Does this sound normal, or like there is something wrong?
I will try to connect a bottle of diesel straight to the pump next time I have a chance to work on it. (it is standing outside, and the rain season has started here on the west coast of Sweden :/ )
Good tip, Thanks!

 

[BobMurphy]

Pumping the primer pump doesn't work well if the air/diesel can't go anywhere - the whole system becomes pressurised.
Unclip the pump output hose, hold a container under the outlet and pump away - you should get a gush of diesel fairly quickly. If you don't, you know which part of the system to investigate.
Bob.

 

[mhhs]

Unclip the pump output hose, hold a container under the outlet and pump away - you should get a gush of diesel fairly quickly. If you don't, you know which part of the system to investigate.

I have tried this, and there is fuel coming out when pumping. I also filled the hose down to the pump as good as I could before remounting it.
Could it still be that air is sucked into the fuel line when trying to start?

 

[BobMurphy]

If you've done all that, a bit of air should clear very quickly. I doubt air in the system is the problem.
Are you getting diesel at the injectors (slacken the connections on two of them) ??
You need fuel, air and compression - which of them is missing (maybe more than one!) ??
Bob.

 

[mhhs]

I have a feeling that it is the fuel that is the missing piece, but I am not sure.
Can I just loosen the connections of two (?, any two?) fuel lines at the rear end of the pump, and try to crank? Or how do I test this?

 

[BobMurphy]

Loosen two connections at the injectors - not at the pump.
Bob.

 

[mhhs]

Loosen two connections at the injectors - not at the pump.

Okay, will try that as soon as possible.

 

[frank rabbets]

Put a live + feed to the full pump? if it is like the 80.

 

[uHu]

Chiming in based on my limited experience:
1
The electric connection from the EDU to the injection pump (IP) is known to fail, with a close to 100 % certainty on the early production years. There is a plug on the spill valve (SCV) on the IP which looses spring pressure on the two connector pins. Easy to replace only the two females. The EDU needs a very good ground and 12 V supply. The power it draws is not that high on average, but as it delivers a 150 V steep pulse, it takes quite a bit of power during those very short pulses. Any rust on the grounding bolt can make it fail, or any loose or corroded connector in the EDU plug.
2
Since your 100 is from the first 3 years of production, you have a solenoid controlled, vacuum powered choke valve on the air inlet. The vacuum hoses have a habit of leaking when they get old, and the air pipes through the top cover is a complicating issue.

 

[mhhs]

Put a live + feed to the full pump? if it is like the 80.

I am not sure, but do not think this is possible since it is an electronically controlled pump on the 100.

Chiming in based on my limited experience:
1
The electric connection from the EDU to the injection pump (IP) is known to fail, with a close to 100 % certainty on the early production years. There is a plug on the spill valve (SCV) on the IP which looses spring pressure on the two connector pins. Easy to replace only the two females. The EDU needs a very good ground and 12 V supply. The power it draws is not that high on average, but as it delivers a 150 V steep pulse, it takes quite a bit of power during those very short pulses. Any rust on the grounding bolt can make it fail, or any loose or corroded connector in the EDU plug.
2
Since your 100 is from the first 3 years of production, you have a solenoid controlled, vacuum powered choke valve on the air inlet. The vacuum hoses have a habit of leaking when they get old, and the air pipes through the top cover is a complicating issue.

Previous owner (or more likely the workshop) removed the connectors and hard-wired them together. I guess they also suspected this, but then totally missed that the EDU needed a solid mount to ground. Since they cut of the connector also on the pump side, I also needed to connect them in another way when I replaced the complete loom. Measuring the resistance on the EDU connector between pin 4-5 gives about 1.5 ohm, so I think that connection to SCV is okay. I have tried with a separate ground wire from the EDU mount to battery without success. Inside of EDU connector looks like brand new.

Interesting with the choke valve. One of the hoses looked bad, so I replaced it. The one going to the top I have not touched. When is it opened and when closed, this is, does it need vacuum to open or close? Is there some way I can disable it or test this?

I have bought a can of diesel and a transparent hose, so will try to feed the pump just to make sure the filter/primer is not the problem. Will investigate as soon as possible.

 

[mhhs]

Now I have had the time to work a bit more on the car.
1. no diesel at the injectors, so fuel is the missing link
2. transparent hose directly to the IP and gravity feed with diesel without success. Diesel does not seem to get anywhere. So, primer pump does not seem to be faulty.
3. choke valve at inlet is open. Cut 2cm of the vacuum hose since it looked a bit cracked in the end and put back. But still, the valve is open, so air is not the missing factor

What do I do next? I am very puzzled by this!

 

[uHu]

I would peruse the FSM diagnostics section and start checking. Or just hand it over to a diesel specialist workshop.

 

[mhhs]

As per my first post, I have followed that guide and everything is according to specification.
It is not until DI-71 guide I get a kind of strange result. I am measuring 5v on SPVF on ECU which should be 9-14v.
Could someone verify that it actually should be 12v?

 

[Shayne]

Wrong size fuse limiting current ?

 

[mhhs]

All fuses are exchanged for new ones according to specification when I had the junction box out. Still I am not sure it really should be 12V since the picture on page DI-71 shows a diagram with 5V marked on it. Could there be a print error in the manual, or is that highly unlikely?

 

[mhhs]

Immobiliser indicator on dashboard is blinking and stops when the key is inserted. Is this enough to draw the conclusion that the immobiliser is working as it should?

Investigation continues and it seems like the immobilizer indicator is not enough to be sure about the immobilizer function.
Got hold of a Techstream dongle and found an error code
99(1) Engine Immobiliser System malfunction, Current.
Next, need to find out what this means.

 

[Shayne]

Bent key ?

 

[mhhs]

hmm.. I do not think so. I have 3 keys with which the indicator stops blinking. One is broken (cracked case), but it does not start with either of the other two. I would assume the key is recognized since it stops blinking? I also have a smaller key that is in another color, and with this one the indicator continues to blink.