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Hi all well here the story having got my piazza up and going only to find it has no get up and go , my wifes toyota crown which is a big heavy car with a 2l supercharged motor not really a go getter has more get up and go than mine .
So here what is happening , the motor has a miss every so often at idle, it wont idle when first started but will idle when you drive 100m down the road lately the idle as gone up to 1400rpm which was idling at 1000rpms when you put your foot down it will boost to 8psi but seems to be lazy it seems to miss and under load have check timing, could it be a sensors or something like that , is using a lot of fuel , the motor has a 3" exhurst from dump pipe , not to sure what has been done to turbo but motor was rebuild by monkey by the looks of it have wire hang of all over the place where they go who knows , could it be a sensor eg o2 , or so sensor not working can any one help wayne

Could be anything fella. Bit hard to diagnose an engine over the internet.


My best suggestion would be to get your hands on a Factory Manual. It gives you all the info and steps to go thru to find and fix faults.


If your idle is all over the shop its got to be a fuel/ECU issue. To be safe id check the timing and fit in some new spark plugs (NGK BP6ES 11)

Have you tried to get any fault codes out of it?????


Bob.

that a good idea I feel silly should have check the codes this may sound dumb but having owned skylines with rb20 motors, do you check the codes the same way eg check the red and green lights on the computer and count the flashes

Yeah that's the one they're made by the same company that made Nissan ECU's. You've gotta do some procedure thing with the accel pedal and ignition switch and unplug the jumper thing that's dangling around behind the dash. It's all in the service manual.

Bob is right, spring a few bucks for the manual, Piazza computer doesn't have lights but it is the same principle, the flash is on the dash (poetry no charge) once you fit the bridge. But before even going there you should check all the constants to eliminate them. If you don't do that first playing with morse code is a waste of time.
Constants are, compression test, leakdown test, valve clearances and valve timing (especially as it has been rebuilt to an unknown standard) Those are the mechancial issues. Next you need to check the injection system and turbo, check for air leaks on manifolds or turbo piping, look for cracks in wastegate seat and make sure it is closing properly. Check throttle body spindle for wear, TPS operation etc. etc. and you could have shitty injectors, high resistance plug leads, the list goes on and on and on..............

However you do it be methodical, ECU's are quite reliable so I wouldn't go jumping in there as a first choice, you might just have a vacuum hose in the wrong place.

I have had my share of piazza woes, from poor running, lack of power, fluctuating idle, cutting out for no reason, won't start on rainy days etc etc. Always managed to sort it and it was NEVER the UCU or anything fundamental. It has always been something touching something it shouldn't or not toucing something it should.

Get your three best friends to help you,a tray of stubbies, a multimeter, and a MANUAL

Oh yea thats right the red and green LED's on the ECU are to show the O2 sensor output red - lean, green - rich and it's supposed to flash between them really fast in closed loop.
Nothign wrong with doing an ECU check to begin with since it's so easy to do. Easier than going around checking all the sensors manually..

many thanks for the advice do you know where I can get a manual or I did see on the forum that someone was selling it in cd is it still avaible cheers wayne

still available as far as I know, try clicking on the flashing message at the top of the page you are looking at LOL