4.2 EFI fuel Injectors

[kbchez]

I would like to know. The fuel injectors in the 4.2efi, do they all operate at the same time, or are they timed to the cylinder firing order.

I'm taking them out and giving them a service. I didn't realise how simple they are to service, and lots of money saved as well.

[the evil twin]

They open individually for each cyclinder.

Don't know quite how you can 'service' them without a pressure tester and flow bench tho

[kbchez]

go to utube its all there.
My injectors now spray correctly and dont leak. The bottom o rings, some where loose in the manifold.
The electric contacts are rusty need to file them up.
The worst part was finding the 4 bottom bolts that holds the plenum on.

[dom14]

go to utube its all there.
My injectors now spray correctly and dont leak. The bottom o rings, some where loose in the manifold.
The electric contacts are rusty need to file them up.
The worst part was finding the 4 bottom bolts that holds the plenum on.

Yeah, you can service them at home by cleaning electrical and mechanical bits that are exposed.
To test them properly for proper operation, I guess you would need proper testing equipment.

[kbchez]

HI All,
My mission is complete.
While the I had the time, as I had to wait a day for my gasget to arrive, I reset the tappets. The info in the manual said set them to a cold setting I think that was .20mm. so I did. Finnally engine back together and tryed to start ...well what a problem.. would only run at 2000rpm. and no air in the fuel systerm. What the fffff...kkk. had a coffee. Think. then I reset the tappets to a hot setting..and guess what the engine ran nice. Yahoooooo. BUt the tappets rettled. reset and yep quiet now. this engine has never run so smoothly and since I have owned it fore about 3mths Its never Idled below 1000rpm.. When warm It idles at about 750/800 rpm... Now I can hear other noises. closed bonnet. here is a utube link on how to clean injectors at home.

https://www.youtube.com/watch?v=IJyhavmmvHw

There is alot on how to clean the injectors on u Tube.
It may not be perfect, but once they are cleaned, with carb cleaner, and spray correctly theres not much else needs doing.
Also I have removed the last of the LPG stuff. I am hoping the fuel comsumption has improved lots.
If it was not for this nissan patrol web site I would not have found the 4 bolts that bolt the plenum to the manifold.
Thanks everyone for the posts, I was reading posts back to 2009. to get the info.

[TJsGQ]

Kbchez loving all the info you have put for the TB42E mate!! Really good reads.. What do you think made the biggest difference for you..? I'm thinking about going down the lines of servicing the injectors or adjusting the tappets on my trol as she's the same highish idle and she's loud af!!! MAF clean made a little difference.. She's just hit 210000 would love abit of info on how to adjust the tappets as I have no idea but Kean to have a crack..! Your a legend from all us efi 4.2s mate

[Irish]

When I did mine:

70538

70539

[kbchez]

I don't think I a legend though.
Setting your tappets is easy as long as you follow the the book. I found to turn the engine over I put a 19mm spanner on the power sterring nut and it easy to turn the engine over slowly. Its easier with the spark plugs out.
To set idle the screw is on the rear of the head drivers side next to the orange bung.
reset the Idle down to 650revs. So when its cold it runs at about 1200 revs.
Fuel now at 18l per 100ks. measured from Albany to perth and over about 800 ks.
Now a small problem I have a light on the dash that comes on under full excelleration up hills etc. this light does not say on it goes out after a few seconds. It's on the top left corner of the dash cluster. looks like a fuel injector spray. I hope its not to much of a major.
Now I still have a small engine miss. Only things I think it could be is coil, distubutor eletronics, or leads. spark plugs are all white in colour.. and no oil on them.

[Parksy]

A miss could also be a vacuum leak. Mine leaked from the head/manifold gasket.

[Bernas]

I my TB42E, one of the injection is not spraying. I have swap between it, but still not. Looks like control sognal problem. Any body have experience this before? thxs

[dom14]

I my TB42E, one of the injection is not spraying. I have swap between it, but still not. Looks like control sognal problem. Any body have experience this before? thxs

Dunno. Chase the electrical wires from the offending injector & try to find the real reason, whether it's a loose connection or something else.

[Bernas]

I have test the ecu output's terminal to injector, looks like no signal to injector, and this is only at 1 terminal where injector having problem. The remain 5 terminals were ok. The question now, is this usually ecu problem or signal to ecu that coming from cranks angel sensor at distributor? In Jakarta to find replacement of ECU or sensor for TB42e is almost impossible and this is really frustating ... Any suggestion? thanks

[dom14]

I have test the ecu output's terminal to injector, looks like no signal to injector, and this is only at 1 terminal where injector having problem. The remain 5 terminals were ok. The question now, is this usually ecu problem or signal to ecu that coming from cranks angel sensor at distributor? In Jakarta to find replacement of ECU or sensor for TB42e is almost impossible and this is really frustating ... Any suggestion? thanks

Clean the crank angle sensor & distributor?
And perhaps after that, order an ECU from a wrecker in Australia?
ECU failure is possible, but not likely I think.
Most likely ECU is either getting a wrong signal or not getting a signal from a sensor etc that is related to the offending injector.

[Bernas]

thank you, will try it

[kbchez]

Hi all, back again,
I found my hesatation at start off . Yep a blown manifold gasget. The gasget was in 2 bits. All the inlet gasket where inderviguals . I also ended up with a blown head gasget. Head planed new hoses as well including heater and bypass hoses. It was cheaper to buy the set of hoses. Same with head gasgets . Cheaper to buy the head set. I didnot use all of them. Now the engine runs smooth and no more vacuum leaks. I hope. The heater hoses had been cut when it was running on lpg. Now i have out the proper hoses. . But wait there is more. With the engine running smooth quiet. Not rattling tapperts. Exhasut leaks and rattles gone. I can hear a bearing rattling. Its the aircon or steering pump.. or idler bearing.