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Hayabusa running rough? MAP sensor?
Jon Ison - 18/2/17 at 08:29 PM

Been at Cadwell today, car ran perfect until almost end of day.

Sudden loss of power, when I got back to pits rough idle, bit of backfiring out of each inlet, getting dark loaded up and came home.

Typical MAP sensor symptoms? I'll have a look tomorrow, tips on testing it?

Thank you in advance.

Jon Ison - 19/2/17 at 10:43 AM

I don't think its the MAP, checking this morning I can see its not been connected electrically and been that way for ever.

Checking the wires to it 2 have around 4.9v and one is earth, there's no plug the loom, years ago it came without one on it, I went this morning hoping to just pull the pipe off and it would run then when I checked I remembered its never been connected.

43 psi fuel pressure,
Disconnected PC unit to eliminate that.


Current position, difficult to start but will start.
Runs in surges as if its hunting
Intermittent random back fire though all 4 throttle bodies.

Any input appreciated.

perksy - 19/2/17 at 03:53 PM

TPS ?

dave_424 - 19/2/17 at 05:47 PM

I've had a similar problem, rough on idle, misfiring like crazy at any RPM. However unplug the pipe to the MAP sensor and it runs perfect

Jon Ison - 19/2/17 at 06:00 PM

quote:
Originally posted by dave_424
I've had a similar problem, rough on idle, misfiring like crazy at any RPM. However unplug the pipe to the MAP sensor and it runs perfect



That's exactly what I was expecting to do this morning having read elswhere the very same symptoms & cure, it wasn't until I pulled air box off to get to the sensor I realised it had never been connected in the first place.