Hi Fred. I made and fitted a larger throttle cable quadrant to my ITBs to help with the jumpy/erratic issue. I also offset it to give a progressive,
rising rate action. The spindle centreline is on the red dot.
Photo Archive
Building: 2 litre zetec, live axle, throttle bodys and megas
posted on 21/7/20 at 07:14 PM
A long time since i did anything with megajolts but if you did the throttle calibration it autosaved and then you should see the top and bottom tps
figures that should line up with your map settings if not correct then the map will need adjusting.
Paul
quote:Originally posted by bikecarbfred
right the problem abit better explained below;
while car is driving with megajolt running at the same time on the laptop. it is all over the place and jerky.
And on neutral gear, car still, the tps does not move.
The only time the TPS acts properly is when the car is switched off and then it is nice and smooth on the megajolt software.
Check your wiring. If it acts that way when the engine is running and works fine when the engine is off it could be a ground issue or some other
interference. I had a similar problem with mine, but it turned out to be the tps connector that was wonky.
So there seems to be not much voltage change for first bit of the turn from 4.8V then it suddenly drops to 2-3V, there after the range is good all the
way down to 0V.
But also as I'm turning it down slow around 1.5V mark the voltage jumped back up to 1.6V.
I know megajolt is scaling the whole range but what would you think this volt meter test is showing.
The TPS along with the carbs were brand new and have done probs 5000 miles on them.
Another video showing nothing happening for first bit of the turn, then after that not a smooth transition.
Also the cbr600 F4 1999 connector should be wired as: pin 1: ground, pin 2: signal & pin 3: 5V
So middle one is usually signal. but for last couple of years i had to put 5v to middle and signal to outer pin to get megajolt to recognise it.
Looks like from day one 5V from megajolt has been going to signal pin of TPS sensor and signal wire from megajolt has been going to the 5V pin of the
TPS sensor.
ONly ground cable was connected correctly to TPS.
This is the only way megajolt accepted the signal. No one picked up anything wrong with throttle caliberation when it was dyno'd
What now? Megajolt does not recognise it any other way when trying to calibrate it and never has done if wired correct.
I've tested TPS in the house on a multimeter. Range is alot better; soon as you turn tps there is no voltage drop and this time goes from 0V to
5V;
but when connecting to Megajolt you have to wire it incorrectly for mega jolt to recognise it.
It then it does what shown in those videos posted above.
in house test: TPS sensor : PIn 3 ground:_____pin 2; signal:_____pin 1: 5V:____ works from 0V up to 5V
in car test: PIn 3 ground :____pin 2; 5V :______1: signal pin: works from 5V down to 0V
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