Dodge Nitro diesel - Is my electronic throttle position sensor faulty?

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Thu 7 Aug 2014 18:24
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321
Hello, I have a dodge nitro 2.8 crd diesel 57plate, I cannot get it to start, it is turning over but not firing. With ignition on the electronic throttle positron fault light stays on

I have taken the inlet manifold off - when ignition is on, throttle body is constantly buzzing/fluttering and the cogs are trying to move almost like it's jammed. I have taken it off and taken the crimped cover off to reveal cogs no visual damage as such, plugged it in and cogs trying to move almost like it's unsettled and trying to get into position.

I'm sure this behaviour is not normal, could this cause the electronic throttle light to stay on? And, cause problems elsewhere causing a non runner?

Many thanks
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Thu 7 Aug 2014 18:27
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - elekie&a/c doctor

What fuel pressure do you have?Needs to be around 150 bar for it to fire up.

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Thu 7 Aug 2014 18:39
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321
Fuel pressure seems all ok run that on the live data. Do you think the throttle position light being on will cause all this havoc? As above the cogs, little motor are acting very peculiar, I'm assuming that it is at fault acting this way?

Edited by Woddy321 on 07/08/2014 at 18:40

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Thu 7 Aug 2014 21:06
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321
Right then!! I have just gone down to do my own diagnosis with my own diagnostic machine (cheap one) as I am loosing faith with this other guy, and his ability to use his own machine, here is what I have found-

Live data shows: with booster pack to the battery, 170/180 RPM / 0.0 psi fuel pressure with ignition on and 380/400psi (26bar) max when cranking

On it's own battery without power pack: 150/160 max RPM and 250psi max fuel pressure

Engine "seems" to be cranking ok but starter motor just might not be up to it?

I taken the outlet pipe of the fuel filter with ignition on and fuel was gushing out so lift pump is chucking plenty to the common rail.

Any suggestions?

Cheers

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Thu 7 Aug 2014 21:25
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321
Sorry I meant the low pressure pump on the filter is pushing enough to the high pressure pump
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Thu 7 Aug 2014 22:00
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - elekie&a/c doctor

26 bar fuel pressure is not even close.Needs to be a minimum of 150 bar before the engine even thinks about firing.

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Thu 7 Aug 2014 22:30
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321
Ok I'm with you - I'm hoping it is not the fuel pump, any other possible culprits ie. fuel solenoid, regulater etc?

Many thanks
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Fri 8 Aug 2014 12:38
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - dieselnut

Anything that is connected to the common rail that is leaking wil loose pressure. It could be the pressure regulator or one of the injectors, or it could just be that the pump is badly worn. Is there any metal frag in the filter.

If you connect clear pipes to the injector spill connexions, see if one is leaking more than the others. The regulator will probably part of the high pressure pump.

Have you tried easy start to see if it fires?

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Fri 8 Aug 2014 12:52
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321

Thanks for the reply,

just tried towing it and did not fire - ALTHOUGH, fuel pressure is now at 3000+psi cranking when stationary as opposed to the previous 380psi when cranking, so I'm guessing that the towing has helped build the correct fuel pressure up. Fault code P0813 has now popped up which is "fuel temp sensor high input". Something is just stopping them injectors from openening

I think where heading in the right direction with it, just want to try cure it myself if I can before it goes to main dealer

I'm not to keen on the easy start, we did spray a few very fine mists over inlet and it did try to start, but not enough to here it run.

Cheers

Edited by Woddy321 on 08/08/2014 at 12:55

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Fri 8 Aug 2014 13:27
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - dieselnut

Fault code P0813 has now popped up which is "fuel temp sensor high input".

I can't see that would stop the injectors firing.

It sounds like the sensor is disconnected or open circuit, the ECU would normally just assume a middle value to calculate the injection amount.

The ECU should just need timing information from the crank/cam sensors & sufficient fuel pressure to inject.

I'm no fan of easy start but just suggested it to see if the engine woud actually fire if thre was fuel.


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Fri 8 Aug 2014 13:47
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Woddy321

Sorry P0183 I meant, my mistake.

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Fri 8 Aug 2014 13:59
Dodge Nitro diesel - Is my electronic throttle position sensor faulty? - Railroad.
You said in your first post that you had throttle position fault. Diesel engines do not have a throttle valve in the air intake like petrol engines do. They do often have an anti-shudder valve which does resemble a throttle valve. This could be stuck closed and preventing the engine from drawing air. Make sure air is being drawn and that the MAF sensor is reading it. The engine will not run if it's drawing its exhaust gasses back. Diesel engine speed is controlled by metering the fuel, not by allowing more or less intake air.
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