Tunerstudio with Speeduino

[Bruce.m]

Is there a TPS lag factor drop down when using the Speeduino ECU with Tuner Studio ? I can't see it in mine but I can see it when I'm using a MS2 with TS.

Haven’t seen that either. Assume that is for Acc-enrich? Speeduino uses a minimum TPSdot setting to ignore noise, which is different to the % used by MS.

[Bruce.m]

Couple of updates to log here.

Firstly the pcb connector on the NO2C Speeduino board is not great. It’s a micro molex size which is only suitable for very small wires and it’s not up to automotive use in my view. I had a couple of pins come loose in the plug & disconnect causing the TPS to go dead & a temp signal too. I have now hard soldered the fly leads instead, & those wires go to a few grouped Deutsch connectors (power / earth is one, coil & injectors trigger wires is another, sensor wires a third etc). That means I can disconnect some sections of wires independently rather than using one large multi pin connector. Helpful for diagnostics…..,

Which neatly segways to the second issue.

I’ve had a reoccurring problem with a noisy crank signal on power up (before cranking). The ECU powers up & immediately the rpm jitters reading up to 8k rpm. This causes the coils to fire and more annoyingly the fuel injectors to dump fuel into the intake while the engine is off. I’ve changed settings to try to get the ECU to ignore the noise (since it’s not getting a full lock) but because it’s not in the “cranking” rpm window it’s not been easy to solve that way. The noise stops after a couple of seconds but that’s enough to flood the engine & get a cloud of white smoke.

Spent quite a bit of time eliminating various sources such as the fuel pump, which it isn’t. Finally figured out today that it’s the wideband O2 sensor or module. If I unplug the power to the WB module the problem is gone. If I leave the module powered up but disconnect the fat sensor cable, the problem is also gone. Disconnecting the signal wire back to the ECU does not fix it (although the noise maybe is less). So either it’s noise via the power / earth wires or the fat sensor cable is leaky. It does run next to thecrank signal wire (shielded!)

[Piledriver]

I went full anti-EMI nuts on my first install, the coil and fuel drivers (peak and holds) went in another MS1 box on the other side of the car with a plastic AMP connector and shielded cable (industrial connectors vs milspec)... as did the harness for fuel//ignition. Sensors/ecu and related harness all on other side of car. Later realized it was ridiculous paranoia induced overkill, but not actually wrong.

Isolate. Reroute. Shield. Wires crossing at 90 degrees have 60dB of isolation... or so they say.

Most WBO2s these days have a separate heater ground to be attached away from ecu, engine perhaps.

I grounded everything to the ECU mount to avoid alternator noise, then I put in a CS130D alt which actually cured it.
(22v clamping diodes to suppress any voltage spikes to ECU, GM can do good work... pretty much all modern alts that have brushes use those or simlilar diode setups)

Perhaps some modern diodes could retrofit a T1 alternator?

[Bruce.m]

I changed the WB module to the “oem” setting which waits until exhaust heat is detected before starting the PWM heater signal (after condensation is eliminated). That did not fix the problem so there is some form of signal at power up regardless.

I’ve made a temp fix by setting the fuel pump prime to zero seconds, so the WB module does not power up before the engine is cranking. Once the engine is cranking or running the interference doesn’t seem to be a problem.

I’ll do some more testing in time and work on better isolation.

[Bruce.m]

Out for a run. Probably the last weekend with summer weather.

[Bruce.m]

Update on the phantom crank noise which caused spark & fuel before cranking.

As above the WBD is the source.
Realised the WB module earth is connected to the ECU & not a true star earth, so cut the earth & ran an extra fly lead instead. Did a couple of power cycles & no sign of the phantom noise (triggers the rpm needle in TS). Hopefully that will fix the issue

[Piledriver]

Good work.

If it still gives intermittent issues find a handful od largish clip-on ferrites and clip them on the offending circuit or cable.
(also available in ribbon cable format)

Has fixed far more things than most electronic techs would prefer to admit to,,,

Also, don't forget to lubricate your connectors properly.
It keeps aircraft from falling out of the sky.