Diesel compression test not the same as petrol?

[Dave]

Diesel compression test via the glow plug holes! compression kits for diesels come with glow plug adaptors BUT im not sure how to stop the engine from starting up :unsure: do I just pull the fuel pump rely? it is EFI! I have looked via your search and trough your videos and even on YouTube for other videos with no luck no rush I know your a busy bloke :pinch: and need the opportunity,s to do particular videos. Thanks Erik hope all is good. Dave

Topic

[W00DBar0n]

What type of diesel engine?
Because if it has huei injectors you could pull their relay.

[LJ11194]

Clear flood crank if it’s new enough.

[EricTheCarGuy]

That’s a great idea and one that would go great if I can get my hands on a TDI. It really depends on the system. That’s something I’ll defiantly have to add to the list of videos I want to do. Thanks for the suggestion.

[who_cares]

usually diesels have mechanical pumps only (i’m not a mechanic, i’m just basing this assertion on my experience as diesel car owner). If the car in question is an old one there’s probably only one pump and you can stop the fuel flow by unplugging the solenoid on the pump itself (shut-off or cut-off solenoid if i remember correctly), which is how the engine stops when you turn the key in the off position. In this case you could have also to consider if the solenoid valve is normally open with signal applied or viceversa, btw you know this stuff, even though i guess it’s probably always ground applied when the engine’s not running and powered on when you turn the key (just using common-sense, i’d think it’s not that good to keep a solenoid always energized and then shut it off for a little while, but everything’s possible).
If the engine instead is common-rail it has at least two pumps, one for low pressure and one for high pressure plus an optional one in the tank (which mine doesn’t have). Here you can easily unplug all the injectors. The main ecu will give you dtc for sure but i think it’ll keep allowing the starter to run.
There’s also another type which is called “iniettore-pompa” in my language, so i guess injector-pump literally translated, but i think it’s a pretty rare kind.
That’s all that comes through my mind now, as i said i’m not a mechanic so something that i said may be not completely right.
Sorry for my english btw

[Dave]

The engine is a Toyota 2L-TE it dose not have huei injectors just the old style. It is 20 years old so most likely dose not have clear flood mode. there is a wire to the fuel pump if I disconnect that or fined a relay to the pump I THINK that should prevent it from starting but im not sure hopefully the master Jedi reveals all there is to know about performing the test. hers two pictures I found of my fuel system,s main parts ie pump and injectors

Attachments:

• injector.JPG
• pump.jpeg

[who_cares]

I doubt that the pump has a relay because it does not draw any substantial current, i’d rather say it has a fuse, probably neither, i don’t know.

EDIT:
i did some quick research and it seems that this pump is pretty different from the bosch VE i’m familiar with, and that thing on top right is the “spill control valve”, so i don’t anymore.

[dollman0]

Hi, this is a pump line nozzle system, there is two options to prevent start up.

1. remove all the glow plugs, no compression means it will not start. No need to go full throttle like on a gas engine, this will just flood the head with fuel.

2. disconnect the wire that shuts off the fuel at the injection pump. there may also be a fuse to the injection pump. I am unfamiliar with that pump because I work on industrial engines and big stuff.

Take care

[Author]

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