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VR v6 all 6 spark plugs carboned

pete30nz

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Hi people

Spare cas, spare dfi and coil packs set replaced. New spark leads. Spark plugs and oxygen sensor replaced new about 1000kms or less ago.

Was doing some work on the car, had the car running for short times and a couple of road tests for no further than 1km.

Car was at home and started running on less cylinders. I checked and cleaned spark plugs and the oxygen sensor which were all black.
I do have new valley gaskets to replace in the next few days if all goes well. Would valley gaskets be a symptom?

What else should i check people?

Pete
 

losh1971

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Might be a faulty O2 sensor. I had a brand new one that was faulty from factory.
 

pete30nz

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Might be a faulty O2 sensor. I had a brand new one that was faulty from factory.
Cheers for your reply losh1971, I guess I'll Google how to check oxygen sensor with multi meter?

Pete
 

losh1971

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I think you hit them with a map torch and test the resistance with different heats applied.
 

_R_J_K_

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had the car running for short times and had the car running for short times and a couple of road tests for no further than 1km.
While they still shouldn't foul up too noticeably, short tests while the car is cold aren't a real good indicator as the ECU will be dumping more fuel than usual into the engine to get it to temp. You really need to look at them after a drive where the car has been at operating temp for (IDK) like 10 or 15 minutes at a minimum maybe.

Does it run right now? The missing is likely to have caused them to foul up if it's injecting fuel and not combusting, then it intermittently combusts when there's heaps of fuel in the chamber which means the mix is rich fouling the plugs. What's the part number on the spark plugs?
 
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pete30nz

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While they still shouldn't foul up too noticeably, short tests while the car is cold aren't a real good indicator as the ECU will be dumping more fuel than usual into the engine to get it to temp. You really need to look at them after a drive where the car has been at operating temp for (IDK) like 10 or 15 minutes at a minimum maybe.

Does it run right now? The missing is likely to have caused them to foul up if it's injecting fuel and not combusting, then it intermittently combusts when there's heaps of fuel in the chamber which means the mix is rich fouling the plugs. What's the part number on the spark plugs?
Hi rjk,

The plug part number is ngkr bpr6efs 15
I'll clean the plugs and the oxygen sensor again shortly and take it for a drive.
I'm guessing it's the fouling that's making the car start missing /running rough.
I'm sure if I went to start it now that itit will run, but it would be running rough

Pete
 
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_R_J_K_

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A lot of the time it's a bit of viscous a cycle. The plugs foul for some reason (leaky injector, combustion issues, misfire), then in turn the fouing makes the initial problem worse via more misfire or whatever.

In response to your initial post, valley typically gaskets won't do this, usually they just leak oil into the coolant when they go. Are all the plugs fouled or just one side? VN-VR all use bank injection so if the plugs are all fouled on one side it's kind of telling. Other places I'd start looking are around injectors and the fuel pressure regulator, possibly the map sensor, also busted coolant temp sensor is one that would cause a lot of issues like this..
 
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pete30nz

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A lot of the time it's a bit of viscous a cycle. The plugs foul for some reason (leaky injector, combustion issues, misfire), then in turn the fouled plug makes the initial problem worse via more misfire or whatever.

In response to your initial post, valley typically gaskets won't do this, usually they just leak oil into the coolant when they go. Are all the plugs fouled or just one side? VN-VR all use bank injection so if the plugs are all fouled on one side it's kind of telling. Other places I'd start looking are around injectors and the fuel pressure regulator, possibly the map sensor, also busted coolant temp sensor is one that would cause a lot of issues like this..
It's all 6 spark plugs. I'll take a photo of the plugs soon when I get to them.
I could try another spare set of injectors.
How to clean the map sensor?
I have a recollection that my iat sensor could be faulty maybe?
I'll check the ECU temp sensor under the alternator also, I think I have a spare some where.

Pete
 

_R_J_K_

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Given it's all 6 plugs, super unlikely to be injectors themselves. Trace the wiring loom for them back and see if they're frayed anywhere though. MAP is usually just a total replacement, you can't really clean them like you can with a MAF (MAP isn't a really common failure though, just something to be aware of).

Have you pulled any codes from the car?
 

pete30nz

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Given it's all 6 plugs, super unlikely to be injectors themselves. Trace the wiring loom for them back and see if they're frayed anywhere though. MAP is usually just a total replacement, you can't really clean them like you can with a MAF (MAP isn't a really common failure though, just something to be aware of).

Have you pulled any codes from the car?
Hey,
I bridged the pins and only get code 12 which is a pass.
About to go pull the plugs shortly and check the oxy sensor
 
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