Single Spark Plug Carboned Up
Discussion
Not sure on the next move. checked my plugs the other day and found no.1 (4 cyl) was black dry and sooted up on the 3 outer prongs but the electrode in the middle doesnt look as bad. the other 3 were fine light brown/grey. swapped the plug with cyl 2 for a bit and the problem stayed in no.1 cyl so the plug is fine.
ive checked for arcing in the dark along the HT leads and coilpack but no arcing visible. leads looks like new and have good connections.
the injectors are all getting 12.05v
no.1 injector shows no signs of a vacuum leak/faulty seals.
I swapped no.1 injector with a known good spare and its no different. car drives ok with power and it idles ok too.
code coming out of the ECU is saying electro mechanical injector no. 1 - open or short circuit. could this be the injector driver inside the ECU has given up the ghost? or maybe the no.1 circuit on the coil pack?
Its not misfiring but I feel it should idle a bit smoother than it is. cant smell fuel.
ive checked for arcing in the dark along the HT leads and coilpack but no arcing visible. leads looks like new and have good connections.
the injectors are all getting 12.05v
no.1 injector shows no signs of a vacuum leak/faulty seals.
I swapped no.1 injector with a known good spare and its no different. car drives ok with power and it idles ok too.
code coming out of the ECU is saying electro mechanical injector no. 1 - open or short circuit. could this be the injector driver inside the ECU has given up the ghost? or maybe the no.1 circuit on the coil pack?
Its not misfiring but I feel it should idle a bit smoother than it is. cant smell fuel.
If I may say so without being condescending, what a good post!
Full details, you've pursued the problem logically, and now, scratching your head, you seek discussion from the Faculty of PistonHeads.
I don't think I can offer any better diagnosis, but examining the trace to the injectors might confirm that one is overfuelling and how. I have a Picoscope, that turns a laptop into an oscilloscope and can display the trace to an injectorl. The cheapest of those is about £100, great if you want one and could use it for other purposes, but still a lot of cash. There is a oscilloscope 'app' for your iPhone: https://itunes.apple.com/gb/app/oscilloscope/id388... for a tenner, but I've never used it, no idea if its suitable for auto use.
This website shows you what you should see, and might be seeing if the ECU control is faulty: https://www.interworldna.com/pico/automotive/pico-...
Otherwise, a trip to your dealer, who should have the kit to do this.
Good luck!
John
Full details, you've pursued the problem logically, and now, scratching your head, you seek discussion from the Faculty of PistonHeads.
I don't think I can offer any better diagnosis, but examining the trace to the injectors might confirm that one is overfuelling and how. I have a Picoscope, that turns a laptop into an oscilloscope and can display the trace to an injectorl. The cheapest of those is about £100, great if you want one and could use it for other purposes, but still a lot of cash. There is a oscilloscope 'app' for your iPhone: https://itunes.apple.com/gb/app/oscilloscope/id388... for a tenner, but I've never used it, no idea if its suitable for auto use.
This website shows you what you should see, and might be seeing if the ECU control is faulty: https://www.interworldna.com/pico/automotive/pico-...
Otherwise, a trip to your dealer, who should have the kit to do this.
Good luck!
John
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