[Paulo_Miguel]

Hello, I have a 4.6 with the GEMS engine, and I have a problem that knows one can identify.

The engine on low revolutions runs poor and I looks that fails in some point’s ….
Connecting the T4 Diagnostic system, we get the following error code;
“Problem on Injector 1, open or electric failure, check connections and plugs”
“Problem on Injector 4, open or electric failure, check connections and plugs”

- The Injector’s are bout new, we already replace the injectors 1 with the 2 and the 4 with the 3, clear the codes, and then again when start the engine we get the same codes on injectors 1 and 2. So the problem is not the injector.
- We test and check the plugs and also the wires from the injectors to the GEMS ECU, with a continuity test, it’s all OK.
- We change the spark plugs and cables for new ones, and get the same errors.
- We test and change the position of the coils (its 4) and the errors are the same ….
- We have now also test a new GEMS ECU and we get always errors on Injector 1 and 4.
- The Crankshaft and Camshaft sensor’s are new.

The diagnostic T4 system always pointing for an electric problem on the Injectors 1 and 4, we think that we check everything related and don’t find anything.

Any one has an idea?????? What can we check now?????

It’s possible to have a mechanical problem? Or a valve problem or timing chain?????

Its possible to have some probems on valves or tapets, or crankshalf or camshalf ????

Any ideas????

Everything is welcome!!!!!!!!!

Thanks in advance and best regard’s
_________________
Paulo Miguel
Lisboa - Portugal
RR 4.6 HSE

 

[Warthog Jnr]

Difficult one, but as you say it does not appear to be the injectors.
As you mentioned you may well have a mechanical problem.
Iwould start with a wet and dry compression test or a cylinder leakage test and work from there.

Good luck!!!!!

 

[CoachDitka]

It sounds to me like the injectors are not being triggered by either the crank or cam sensor (not sure which one triggers what). Try connecting a timing light to the #1 and then #4 plug wires to see if they are firing. Then I would check the triggers for the crank and cam sensors to see if they are not up to spec.

I'll check the Rave CD for a little more info.

*Edit*
Try disconnecting the cam sensor and see if you still have the problem. Then I would try checking the teeth on the reluctor ring that trigger the crank sensor. Possibly some are bent/missing and are not properly triggering the crank sensor for the #1 and #4 cylinder?

-Coach

 

[Paulo_Miguel]

Thanks, for the replays,

I as there again to make some more test´s on the RR.

The cam and Crank sensor´s are new, I tried to disconnect them and the engine stop´s, it means that is normal and they are ok.

Also I tried to disconnect the Knock sensors, it´s not improve, in fact the engine shake more, it also means that they are working ….

I change again the GEMS ECU to the new one, clear all the faults , and when run again the engine, it get again the same error´s.

Now after calling Land Rover Portugal and UK, several times ….. We decide to open the engine, and take out the heads.
It’s possible that the problem is from the Camshalf, exhaust or admission valves, valve springs or extenders to the valves not calibrated.
Or also the timing wells or chain.

Since that we will open the engine, I will order from RPI two complete kit’s for head rebuild, camshalf, timing chain.

This is the kit that I ask for ;

KIT 1
New Valves# (16), New Springs# (16), New Oil impregnated Valve guides# (16), (as used Range Rover 4.6 HSE). Fully enclosed Valve seals# (neoprene),

KIT 2
Piper Torque-Max camshaft, timing chain set, standard hydraulic tappets and all standard gaskets

Mean wile any other ideas are welcome.

Thanks

 

[CoachDitka]

I would still visually inspect the teeth that trigger the crank sensor. If some teeth were broken or sheared off, or bent, they would not properly trigger the crank sensor. I am not sure that a mechanical problem such as sticking valves or weak springs would register a fault. Since you are getting a fault that is electrical, I feel you may be wasting a lot of time and money. In theory, the system should be very simple. You have triggers, you have sensors, you have GEMS, and you have the injectors. You have changed the injectors, you have changed the GEMS unit, you have changed the sensors. The only thing you have not checked are the triggers for the sensors. I woudl eliminate all electrical possibilities before I tore into the engine. If I suspected the valve trane, I would remove the covers and inspect things with the engine on/off and go from there.

-Coach