Not good news for me unfortunately.

Just had a phone call from my mechanic, who has had the car all week and done numerous tests on it.

He says the problem with my car misfiring at low speeds is not a fuel or oxygen related problem !!!!

 

So not only have I just wasted money on an injector and gaskets that I bought from Nissan (less than £200, but it all counts).

He says that it's a mechanical problem which effects the whole left side of the engine (i.e. 2, 4 & 6). He is putting it down to a burnt valve (exhaust maybe). But he has recently lost a mechanic so the job is too big for him at the moment.

 

He is a top bloke and has not charged me a penny which I'm really happy with.

 

However it leave me with a misfire at idle which I need to get sorted.

So I need a mechanic that can sort my problem out, can anyone help or recommend ?

07801 735117 ;)

 

Gimme a buzz m8

Just to make you feel better .... it is possible that the faulty injector has caused lean running, over heating and burnt valve ...

 

Has he proven that the injector works ?

Originally posted by AndyP

Has he proven that the injector works ?

 

Yes by measuring the gases whilst connecting and disconnecting each injector.

Wouldnt a Consult show up one cylinder being down on the rest or a whole bank? A burnt valve would mean much less rpm drop when that one has its fuel disconnected.

 

Also a compression test would confirm it. It would be zero on one cylinder with a burnt valve.

 

Suppose the obvious like plugs has been checked. A burnt valve burns right out pretty quickly and you would hear it plus the hot gases by-passing the exhaust valve might overheat the cat bringing on that warning light. The misfire would be throughout the rpm not just at idle.

 

If its defo mechanical and one whole bank then it could be the cam belt having slipped a couple of teeth on that side but unlikely.

 

Otherwise I hope its a wiring loom issue or duff ptu - anything rather than head off stuff.

bummer, but:

 

1, i thought you done a compression test & all was well

 

& 2, "a" valve wouldnt effect a whole bank

I'm gonna do another compression test tomorrow, as I can't remember the exact results. I'll post the results here once I've done it.

Stuart, check your timing belt, have seen this on a fair few cases now, wherever one bank is concerned the single denominator is cam timing, also this could account for the odd emissions on one side as incomplete combustion will occur if valve timing incorrect.

 

 

Jeff TT

Yes, I will be checking this this weekend, but doubt it's that.

The gas reading are as follows:

C0% & 02 & Lambdaare good and constant on both banks.

Hydra Carbons on left back are between 800 & 1200 ppm

Hydra Carbons on the right bank are 500ppm and constant

 

When a spark is disconnected from the left bank the HC rise even higher.

There are no air leaks as the )2 reading on gas analyser is low.

ConZult shows no faults

 

So this all points to a burn exhaust valve or does it ?

Originally posted by smw1

 

When a spark is disconnected from the left bank the HC rise even higher.

 

well it will do, HC is unburnt fuel!!

Originally posted by Paul C

well it will do, HC is unburnt fuel!!

...which proves that the injector is not at fault.. was my point :D.

well, it proves the injector is injecting, not that the spray pattern is good, its not leaking when shut, its injecting the right quantity etc etc.

dont forget what i said - get it checked with a cylinder leakage tester before just ripping the heads off. ;)

Will do mate, I'll start phoning around this week.