996 cutting out at 7000rpm????? Can any one steer me In right direction please... Definitely electrical as tacho needle dives back to stop then rises back up as engine fires up on over run... Rectifier was done about two years ago, still steady out put of 13.4 at all revs, all connectors checked, fuses checked. At a loss now....Ecu???
Thanks FE, had overlooked that, have already checked pick up for resistence and its fine in that respect, will try to get a look at it later today and let you know what I find. Daz.
Double check all the relays beside the battery, I bent each connection slightly on mine to ensure a good connection. And then held them in place with tie wraps.
Thanks ducv2, will check all the relays again just to make sure on that point. Crank angle sensor was 0.6, fairly certain its not that as it came on suddenly whilst overtaking a line of cars, had been a fairly spirited ride only 10 minutes before so was suprised it fucked about at lower revs whilst ambling past 40mph wankers..... Will go back through relays and connectors again. Thanks for help, Daz.
I once had a similar fault and it was the TPS not reading correctly (going to zero) as you opened the throttle.
Ok after checking and rechecking relays, fuses, wiring etc I went out for a test within a mile it was just shutting down everytime it reved hard between 7000-9000rpm, then 10 miles later at low speed/revs it spluttered to a stop going through a village and refused to re start.... After farting about for about 45mins I managed to get it going and limped home where it died completly half a mile from home, luckily a mate saw and pushed me to top of a hill where I coasted home..... Tacho needle dropped like a stone to the stop, tried turning it over on starter, tacho stayed on stop then occasionally it registered and the engine fired but woudnt keep running..... I then checked the bastard thing all over again and found nothing....changed the engine speed/crank angle sensor did around 40 odd miles, pulled like a train and felt good.....and then I felt a slight hesitation and thought ok might be nowt so carried on, filled up with fuel and started out on a further run, then fuck me on giving it some proper wellie it shut down, tacho dropped to stop so I coasted with engine turning over where the needle flicked and it fired but woudnt run. When I stopped the ecu and fuel pump relays were chattering away......I swapped the relays but it made no difference, I opened up the ignition relay and jammed it in the on position with a twig, the ecu and pump relays still clattered away.....fuckers After tugging wiring moving fuses and checking relays it made no difference, after a while pissing about it restarts, there doesnt seem to be a pattern... But its only happens after I rev it hard between 7000-9000rpm then all the cutting out and silly relay business starts..... Below that it generally behaves, once it cuts out it will continue to do so to the point where it stops completly... Sorry for long post but Im hoping someone can make something of the symptoms Ive described. Thanks, Darren.
Had another go at it today, disconnected both the tacho and the 3 wire alternater plug and its still no different, as you thrash it into the high revs it cuts out then comes back again on over run, can happen at any engine tempreture at any time but still only triggered when the revs are up and under load. Can anyone shed some more light on this, am I missing something??? Daz
bit of a long shot, would it be worth rolling roading it??? that way when it cuts out you wont be miles from home, and you can also check that all the relevant readings for emissions are ok, and not running lean etc, you can also prod bits to see if that causes it to cut out??? and swap bits on a trial and error scenario,
isn't this where the second injector comes in? About 7k? If it's running well below that, then craps out above that...
It's possible that the pump isn't delivering sufficient fuel to cope with the engines demands over 7k, hence why it cuts out, and cuts back in when the available fuel pressure is sufficient. Could be clogged up fuel filter or split fuel hoses.
does cut-out period clear - i.e. - can you ride it above 9K and bike will pull as normal? - if this is the case then it could be the TPS at fault.
Hi Jerry thanks for reply but Im fairly certain that only the P8 works this way and not the 16m that I have, both injectors fire all the time. Daz.
Thanks John, I havn't checked fuel pump or filter as yet but as tank is off I need to eliminate everything, I did change filter and hoses just over a month ago as I do every year, never found much in mesh or pump/filter as yet.... Still appears electrical to me. Daz.
Hi Chris, no it doesn't , just dies and engine turns over on over run anything from 1 to 10 seconds then fires up and keeps going or or just dies, theres no real pattern with it, as I did 40 odd miles and it was fine then played up and died altogether.... Did back probe tps to see what voltage reading was and if it was skipping or showing some form of fault, couldnt really see much wrong tho. Have checked and rechecked all sensors, coils, injectors etc etc but cant detect any shorts or unusual readings.... Daz.
The fact that the revcounter drops to zero indicates that it is an electrical issue, nothing to do with the fuel supply. I'd suggest that it is a resonance issue with vibration at around 7,000 rpm affecting either the crank sensor or, more likely, the injection relay or a connection to it or the ECU.
Im thinking the same Derek, have swapped the relays and fitted another crank sensor which made no difference .... But Ive just pulled plug off ecu and spotted this..... Daz.
Not sure what you're seeing there in the pic, but I guess that some of the soldering is looking a bit dodgy?
Sorry Derek its not a great picture and I dont yet have an app on tablet that I can circle it, off to out to work in a moment but will try later for a better picture.... If you look to the right of the diodes you can see the fingers of what I guess are mosfet type chips, the legs are white and frosted together with staining. Darren.
i'm not sure either ^ but looks like top of the chip in which case it could be a damaged info sticker etc. If you look at the row of small cylindrical bars going up to the main strip loom connector - check for corrosion where they are soldered to the P.C.B. while you're in there. You are probably aware, these are prone to taking on water if ever used in the rain despite the rubber bung being in place - it's only the 'void' sticker strip that seems to stop 99% of it.
