Megasquirt info

Sorry, from what I remember Tunerstudio had a way to define voltage for closed and.full open.and extrapolated the others from that. Maybe use a meter and find out what those voltages are for the tps you are using? Forgive me if it came across wrong before, just trying to be helpful. You could just have a tps with a dead spot or corrosion affecting its voltage outputs if you are defining them in tuner studio based on the fsm it could cause the behavior you described.

If you are using the calibration function in ts where you go wot and full closed I'm assuming that its done key on engine off but your problem appears key on engine on? Or is it never zeroing out after calibration even with the engine off?

If its only happening key on engine on it could be a gashed wire getting crosstalk from a sensor such as the dizzy so it wouldn't show up without the engine running.

The values you see in the Adc values are not percentages. Your ADC values could be anything so long as the full open is higher than full closed and the tps itself is good.

it wont go below 64 period, engine on or off. Brand new TPS. Oll try different TPS's

I'm still not clear on whether that's 64% or 64 ADC counts. When you calibrate it it doesn't matter what the numbers are as long as when you are done calibrating, it goes from 0-100%. And it might be a couple percent off sometimes.

If it's 64%, then you didn't hook it up right, or it's dead.

By %. Its hooked up correctly. I double tripple checked. ge to going to have to check tps's. Ive been working on this car all day and havn't gotten anywere. I tried to run the "autotune" but cant figure anything out. Shit is so vague its rediculous.

Hmm,
This is probably an oymoron, and don't take this the wrong way, you are using a TPS for an automatic car right, or a 240sx TPS (fits z31 throttle body, all of them have the "functions" of the z31 auto tps)?

Was your old TPS busted? Did you try it? or is this a "new" auto TPS that you went and got from a parts store because your car was a manual?

Just trying to fill in the blanks. A schematic of how you have the tps wired wouldn't be terrible either

Did you try backing up your MSQ and project, uninstall tuner studio and reinstall after verifying deletion of all the old data files? I've seen TS get corrupted (happened on my laptop) and it can report false information or send the wrong information to the ecu (ie: your tps calibration).

Yes its a auto tps. I have probably 6-7 auto/240 tps's. I actually just went threw this issue on a sr swapped 240 i just did. Went threw 4 TPS's to get one to calibrate correctly. At this moment im not super worried about the tps issue. Theres wayyyyy bigggger issues at this point haha.

Good luck man! Let us know if you ever find the root cause of the TPS issue, aside a failed TPS, may be useful to others in the future. If you can try to post the values of ohming the sensor poles of the tpses (both good tps and bad tps) that might help others indicate a good/bad tps without all the hell you've gone through

When you stab your cas running the MS did you line it up on the dot like factory or have to move it a few teeth to get the timing marks on the crank pulley accurate?

Don't you need to use a potentiometer style tps when using megaesquirt?

Yes, the auto style that gives accurate tps readings, not the manual 'WOT or closed' switch type. Though with MS, that does free up the WOT contact for 'stuff'

MS just uses the 2 ADC readings to extrapolate a voltage to throttle position map so to speak.

purely an example:
0.5v = closed
5.0v = wide open
2.75v = would be ~50% throttle

When using the factory distributor, did anyone turnthe screws on them dash pots at all? It seems i cannot get a consistent trigger. the composite/tooth loggers ect, show its kinda squirrly. I have my resistor in-line not on the board btw. MSEXTRA says:

"The optical sensor is another commonly used category of sensor. These are almost exclusively a three wire sensor. In CAS (crank angle sensor) units a multiplug may be used to combine multiple sensors. The sensor itself acts like a switch to ground when light shines through the trigger disc. Optical sensors are commonly seen in distributors where vanes or shutters block the light causing the sensor to rapidly switch off and back on when light is present again. The optical sensor requires a supply voltage which is usually taken from the 5V VREF output of the Megasquirt. The sensor is then grounded at the Megasquirt and the third wire connects to the tach input.


The Megasquirt board needs to be set for VR input. V3.0 VR+pullup setting - V3.57 VR+pullup setting
(Note, that previous Megasquirt versions may have used the optoisolator input, but for better high frequency response with toothed wheels and to match the input on the MS3X card, it is advised to use the VR circuit.)

The Megasquirt main board has provision to adjust the trigger threshold on the input signal - these is by two small potentiometers inside the case. These are labelled R52 and R56. Using a small screw driver, carefully turn both about 12 turns anti-clockwise. (There is no dead-stop, but you may feel a "click" when the end position is reached, they can't be damaged by turning too far.) Then rotate R56 a few turns clockwise.
http://www.msextra.com/doc/ms3/ignition.html

V3.57 board - VR Input + pullup
a) Find JP1 in the bottom right of the board. Place a jumper across positions 1 and 2
b) Find J1 in the middle of the board. Place a jumper across positions 3 and 4
c) Install a 1k resistor (any value 470R - 2k2 is likely ok) onto the pads marked R57
d) With a small screwdriver, turn the pots, R52 and R56, about 6 turns to the fully anticlockwise position (you may feel a "click" when the end position is reached, they can't be damaged by turning too far.) and then turn R56 back about 2 turns clockwise.
http://www.msextra.com/doc/ms3/ignition.html#vrv357pull

[quote]Black 89Turbo wrote: When you stab your cas running the MS did you line it up on the dot like factory or have to move it a few teeth to get the timing marks on the crank pulley accurate?[/quote:2le1r7qx]

You have to have the CAS lined up properly, to FSM specs.

You would think. WHen the car was stock, before MS was ever brought into the picture or any modifications for that matter, if you lined up the Cas on the dots (like factory) the timing was a bit off. The cas/distributor always had to be one tooth retarted in order for the timing to line up on the crank pulley OR for the rotor to be on cyl. #1. The car ran flawless, went to the track every week. With the MS its the same situation. Have to have the Cas one tooth off in order for the crank pulley to line up with the timing mark and for the cas to be on cyl #1.. The timing belt is perfect. Car is timed correctly. One thing i stumbled upon during this whole fiasco is the rotor position situation. I will take pictures for that so theres a better understanding.

Hm, the FSM tells you to set it in one position before installing… since the gears are angled, it rotates when you install it. So, you have to have it about a gear tooth off for it to be on cylinder #1 when you install it.

Keep in mind that the cap's cylinder number one on the inside probably doesn't match where the actual plug goes on the outside of the cap.

You could have it off, I suppose, if your offset in MS was off enough. As long as the rotor's near the right plug.

These are all to Z's. I have a total of 4 (including the one in the car now). ALL 4 put the rotor in a different position(other 2 are at the garage). The reason the car would never run before, one of these had the rotor starting inbetween cyl #2-3 if you lined it up with the tooth before the dot so it is lined up with the dot when it slides in. The one in there now puts the rotor sorta inbetween the two. The "4th" one puts it completely 90 degrees to the one on the left, basically farther turned than the one on the right.