vr 5lt questions

[Garth]

Hi there team of experts and legends.

i have a question, i am about to have a look at at vr 5lt that is having issues, it is not starting.

the question i want to know, is there a way to test the hall sensor? as in is there a operational test i can do to check it? not realy in the mood to remove the dissy in it's glory.

i know with the eco and other v series that if you have a faulty crank angle sensor you will not have a injector pulse so i am assuming that it is the same with the vr 5lt

besides checking spark and fuel and pulse is there anything else that i should be looking at? quite a few people have had a shot at this car and all are telling me it's something electrical, it's hard to check a car without any wiring diagrams. so advise will be welcome.

 

[Jxfwsf]

Is it auto or manual? (different ecu/pcm pinouts between them)
Attached is manual schematic

You could measure voltages for the 3 hall effect sensor wires (determine gnd, power and signal) and use an led test lamp on the signal wire to see if it's pulsing..... as a very rough estimate of if it's working or not.
A good dmm or a scope would be even more accurate.

 

[strgas]

unbolt the trigger module and inspect the underside of it , if discoloured and brownish then replace it common for these to overheat and cook .

 

[BlackVXGTS]

In my experience, the Hall Effect Sensor is the most reliable. I would be checking:

1. Ignition module. Not the most common failure but the easiest to replace and test (particularly if you have a spare).
2. Ignition coil. Most common of my failures. Bastard to replace due to the location and lack of clearance.
3. Hall Effect Sensor (HES). Usually gives some warning and fails when hot but does recover when engine cools down. On older cars it's usually better to replace the whole distributor rather than trying to repair the HES. Replacing the distributor is also a PITA due to lack of clearance, and the need to ensure that the leads are in the correct positions, and the timing is correct.

FYI. I just replaced the ignition module on my wife's VS Clubsport a few weeks ago. Started it up, engine seemed a little rough, reversed into the driveway, left it idling for a few minutes and it stalled. Never happened before. Tried to restart - no go. Replaced ignition module with a used spare (previously tested) and car started fine.

 

[Reaper]

unbolt the trigger module and inspect the underside of it , if discoloured and brownish then replace it common for these to overheat and cook .

^^^ this. Halls are usually bulletproof. I'd be looking at the ignition module myself. That said, start with the basics - is it fuel or ignition that is missing?

 

[VS 5.0]

Over the 18 yrs I've had mine, two HES have cacked themselves and only one ignition module.

 

[Garth]

sorry team, ive been caught up with my land cruiser, i havnt looked at this car yet.

History of the car is that it is a auto, there is a guy who is looking at it, they claim to have spark, i dont think they have been smart enough to look at injector pulse, or fuel system. i was going to check the fuel pump operation when i check this car out. hoping to have it in the drive way saturday so i can start throwing things at it then.

so far the guy fixing the thing has fixed a hand full of things, i dont think he is testing rather just throwing things at it. ignition module, dissy cap, rotor button, spark plugs, i was going to check to see if disy was on right way and firing order was correct before i start looking into it more. i will keep everyone updated as time goes on.

 

[Jxfwsf]

Well if it has spark, shove a paper clip in the diag plug and check for fault codes (if you can hear the fuel pump)... if it was me I'd check for codes before I did anything else.

It's pretty much a vn efi system with vats, not very complicated.

 

[Not_An_Abba_Fan]

On the HES note, I munched a cam on 355 build a while ago because the HES was stuffed. Was working when I pulled the engine out, refitted everything and it wouldn't fire. Had an "expert" come look at it and my original thought was the HES, he reckoned nah, never. Replaced the usual suspects and still no go, I fitted a new one from Jaycar for the princely sum of $4 and away it went. Then had to strip and rebuild it due to the flat tappet cam wiping a lobe because of excessive cranking without it firing.

 

[Garth]

well, i must apologize for the delay in getting back to every one, life has been very very hectic. So i now have the car in the yard and have had the lovely pleasure of replacing a few things.
1. the starter motor solenoid failed on me, yay so replaced that, so now it at least rotates.
2. Replaced the coil and disy, now have spark, checked the firing order all plugs are fine, checked the timing by lining up the mark on the hb against the factory markings, had it right in the middle. rotor pointing towards where number 1 should be.
3. have injector pulse (check done using probe and someone cranking, injectors are firing away)
have fuel, i hear the pump kicking in. and see fuel coming out of the hose after the pressure regulator.
when i start the car it tries so hard to start, it coughs and gives it a go, but just wont fire. so advance the timing and retard the timing to see what happens, yet nothing happens. what in gods name am i missing? the only thing i havnt done is a compression test. mainly due to the fact i dont have the tool to do the test. Any advice?