Intermittant Misfire At Idle

[sy300]

If you can remember, a while ago my wagon developed an intermittant miss at idle after the engine had warmed up. It went away while crusing normally, but seemed to use more fuel than normal.

I changed the plugs, it still did it.

It was due a service so I took it in to the Nissan dealership where I get it done. They suspected the coil packs, so checked them out. All good, coil packs fine.

Still misfired at idle.

The mechanic said that it seems more like a 'cough' than a misfire and could be a burnt valve, so did a compression test and a valve efficiency test.

Low-and-behold, inlet on number 1 and 6, and exhaust on number 2 and 5 not looking so good.

The wagon is now in the shop for a bit, while they take the head off and fix it all up for me.

Lucky I opted for the mechanical insurance when I bought the wagon, eh! It should only cost me my excess (NZ$125) and not much more.

Has anyone else had this happen?

P.S. I was just telling a guy at work how reliable my Stagea has been, not even a blown light bulb since I bought it. Irony sux!

[Ska]

BUmmer, thank god for insurance eh!

[fcruz3r]

bummer...i dont have mechanical insurance on my car....it came wif the normal 5k or 3mth warranty...anyone recommend a good insurance company that will do this...and whats involved..like do i need to bring the car in for a full check? ...but the again i dont think it'll be valid unless i leave the car stock standard.

[Ska]

I dont think there is a policy in AU that does this.............? Unless it is covered under full comp?

[fcruz3r]

I dont think there is a policy in AU that does this.............? Unless it is covered under full comp?

well i know most car dealers will offer an 'extended car warranty' to 3 years or 175k at a cost of an arm and a leg... but its all a friggin scam...like they wont cover things such as sticky valves...it'll literaly have to break before the warranty covers it.... i had an extended warranty on my astra...and at 56k..the rear rotors needed replacement..AVG told me to get stuffed and that its 'normal' wear n tear ...i bought the car at 50k...and after driving for 6k's the rotors are unusable and its supposed to be MY FAULT

[Ska]

Tell me bout it, I had the AWVG 3 yr warrantee and so far thing that have broken not covered:

1. Heater Core

2. Handbrake Assembly

Those warranttees are only good to replace whole motors and crap like that!

[pixel8r]

Yeah I got the AWN 12 month warranty with mine and they dont cover any suspension components at all, and what they do cover is basically all the things that aren't likely to go wrong by themselves (engine, trans, etc) unless you're real unlucky.

They were going to pay about $700 towards a replacement turbo (what a joke) but it had to be through one of their listed workshops (how many of us will take our imports to just any old mechanic??). I just paid full price elsewhere. Cost a lot more but at least it was done quick (no waiting months for a workshop thats never heard of a turbo let alone a stagea to find parts) and I could rest assured it was done properly.

The warranty actually cost me nothing so I haven't lost anything - I guess its still better than no warranty at all. Within the 3mth/5000km period everything's still covered by the dealer either way.

[sy300]

The insurance I got (Autosure) cost NZ$1000 on top of the price of the car, so not a big difference. It has a NZ$125 excess on any claim. It covers pertty much anything, except for consumables like brake pads, spark plugs, etc. It covers the whole suspension (not shocks) and basically the whole engine (incl turbo), trans and most electrical items.

It pays out a maximum of NZ$3500. You can get these insurance covers with almost any new import here in NZ. Obviously, it doesn't cover anything that is not factory standard, or if you don't get your car regularly serviced by a recognised mechanic.

I will be interested to find out exactly what is wrong with the valves when they pull the head. I gather this is not a common RB engine fault. I have never heard of it happening to anyone.

[sy300]

Yay, looks like I'll be getting the wagon back tommorow!!

Turns out that it had burnt out a valve, caused by the engine running too lean. Valve replaced and now they are just checking the injectors to make sure that they are all sweet.

Might run a bit better, not that it ran bad before the valve burnt out. My fuel consumption might go up now it's running at the correct A/F ratio. Oh well rather pay for fuel than go through this again.

[Duncan]

very unusual problem....make sure you get the fuel system pressure tested as well as the injector test

normally they ping themselves to death and break the ring lands long before a vavle burns.

[sy300]

Finally got the wagon back all fixed.

Turns out that the a couple of injectors were buggered, causing bad atomisation, incorrect fuel burn and then the O2 sensor sensing un burned fuel in the exhaust, therefore leaning the fuel back.

The whole head had to be reconditioned (all new valve seats, etc) and the injectors replaced.

Whole thing came to over NZ$2000, but thanks to mechanical insurance, I payed NZ$275. All I ended up paying for was oil, filter and a bit of labour.

It sounds different now, much smoother and the turbo whine is less noticable when it's boosting.

Moral - DON'T LET THE ENGINE RUN LEAN!

[fcruz3r]

Finally got the wagon back all fixed.

Turns out that the a couple of injectors were buggered, causing bad atomisation, incorrect fuel burn and then the O2 sensor sensing un burned fuel in the exhaust, therefore leaning the fuel back.

The whole head had to be reconditioned (all new valve seats, etc) and the injectors replaced.

Whole thing came to over NZ$2000, but thanks to mechanical insurance, I payed NZ$275. All I ended up paying for was oil, filter and a bit of labour.

It sounds different now, much smoother and the turbo whine is less noticable when it's boosting.

Moral - DON'T LET THE ENGINE RUN LEAN!

wish they had insurance like that here

[Duncan]

wish they had insurance like that here

they do....the "warranty" provided with most cars is exactly like this, an insurance policy with pay out limits for certain events that could go wrong