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How would I check that my plugs are r type?
Technical random / multiple cylinder misfire
- Thread starter Neilix05
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Technical random / multiple cylinder misfire
Another thing to try, run a cooler plug,
In the case of NGK the number is the heat rating, higher the number the cooler the plug runs
So if you run say BPR6EIX
Change to a BPR7EIX the plug will run cooler so won't glow as much, if I remember right, each time you go up a number it drops the tip temp by 50degrees
In the case of NGK the number is the heat rating, higher the number the cooler the plug runs
So if you run say BPR6EIX
Change to a BPR7EIX the plug will run cooler so won't glow as much, if I remember right, each time you go up a number it drops the tip temp by 50degrees
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Last thing to suggest is one that baffled us for weeks,
We had a misfire on a 1998 Orion,
Tried EVERYTHING, it ended up being an injector,
The windings inside we're breaking down,
Run it cool and it was mint, as soon as it heated up the windings broke down causing a misfire effect at higher revs and hotter running.
Identical to a misfire feeling.
We had a misfire on a 1998 Orion,
Tried EVERYTHING, it ended up being an injector,
The windings inside we're breaking down,
Run it cool and it was mint, as soon as it heated up the windings broke down causing a misfire effect at higher revs and hotter running.
Identical to a misfire feeling.
If it has R it the plug number it is, it's quite hard to get non resistor plugs now a days.
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Mine are BKR5EIX
If you get no joy take it up to BKR6EIX,
What did your plugs look like when you changed them?
White tip is running too hot,
Brown is bang on.
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I cant quite remember, I remember they were bosh+ plugs, but maybe if I take out plug number 1 tomorrow should be able to tell if its running hot from the colour that it is now?
Have you checked the ignition timing,
It's hard because I've never even lifted a bonnet on most fiats
If it was Japanese I could tell you how or what degree to set it to,
99% of Japanese cars up to 2003
You can lock the ignition advance and set them by the cam sensor or distributor to the perfect degree, but I'm sure someone else can jump in and tell how to check or adjust, if possible . . .
It's hard because I've never even lifted a bonnet on most fiats
If it was Japanese I could tell you how or what degree to set it to,
99% of Japanese cars up to 2003
You can lock the ignition advance and set them by the cam sensor or distributor to the perfect degree, but I'm sure someone else can jump in and tell how to check or adjust, if possible . . .
You can, plugs guide you to a multiple of causes and tell you a lot about how it's running.
1st place to check in diagnosis.
Rich, lean, hot, cold, and each one on each cylinder.
Unlikely to be running hot.
5s are the right grade for MPI Sei -- BKR5EZ. A 6 would be acceptable.
The colour of a plug will tell you about the condition of the mixture over the complete cycle of the engine's running. This isn't really of much use as you have no realistic way of adjusting it!
A way to do it on olde school carbed engines on motorcycles was to fit a new set of plugs, and use the kill switch under full throttle, slightly uphill, whip in the clutch and coast to a standstill. You then used an illuminated loupe to read the plug. Try that in a car and you'll lock the steering unless you first wire in a kill switch.
Otherwise, you're just looking for crude stuff like massive overheating, oil, signs of detonation, etc.
Fortunately, gas analysers, lambda probes, etc. have pretty much put this stuff out of use.
5s are the right grade for MPI Sei -- BKR5EZ. A 6 would be acceptable.
The colour of a plug will tell you about the condition of the mixture over the complete cycle of the engine's running. This isn't really of much use as you have no realistic way of adjusting it!
A way to do it on olde school carbed engines on motorcycles was to fit a new set of plugs, and use the kill switch under full throttle, slightly uphill, whip in the clutch and coast to a standstill. You then used an illuminated loupe to read the plug. Try that in a car and you'll lock the steering unless you first wire in a kill switch.
Otherwise, you're just looking for crude stuff like massive overheating, oil, signs of detonation, etc.
Fortunately, gas analysers, lambda probes, etc. have pretty much put this stuff out of use.
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Well, it's a spark plug. And it has fired at some time.
Random/multiple misfire.
Implies that the misfire occurs on more than one cylinder, and on no particular cylinder (or the ECU code would point to the problem cylinder). So I'd not expect any clue from looking at the plugs.
One thing about Iridium plugs is that they cannot be gapped.
Random/multiple misfire.
Implies that the misfire occurs on more than one cylinder, and on no particular cylinder (or the ECU code would point to the problem cylinder). So I'd not expect any clue from looking at the plugs.
One thing about Iridium plugs is that they cannot be gapped.
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As its behaving itself I shan't put myself through the pain of getting no2&3 out as well as trying to line them up to get them back in. Checked the gaps before putting them in just to make sure and they were fine.
OK and thanks
OK and thanks
I'm still thinking maybe injector route,
Take them out place a multimeter on the connection and heat them up with a heat gun, watch the resistance it shouldn't differ too much, any big strange jumps and it could be that.
Take them out place a multimeter on the connection and heat them up with a heat gun, watch the resistance it shouldn't differ too much, any big strange jumps and it could be that.
How do you get random/multiple misfire on a wasted spark engine with 4 injectors?
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Not burning oil, haven't had to put any in since its service in January, not sure whether the oil is just leftover residue from when the rocker started leaking.
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Actually saying about the excessive oil vapour the breather hose going in to the air box is always quite oily
