Issue with initial attempted fire up

[Farmtruck62]

Just got installing a MS3 Pro with LS58x drop on harness from DIY in to a SandRail that previously had a MEFI EFI system.

First time we tried to start a project we had issues with the Firmware being told it was not correct. Downloaded 1.5.0 and that resolved the Firmware issue.

I have Autotune 3.0.28 installed and the owner TJ registered for the I believe enhanced version which I also unlocked on my laptop (since I am helping tune the car).

We started with provided 6.0 58x tune and were seeing some weird things, please see attached screen shot for reference. We have not attempted to fire as:

1) Coolant temp changes with every ignition cycle. We have seen it range from 1* F to 70* F. One ignition cycle it will read warmer than the proceeding ignition cycle only moments later. Cycle the ignition again and it might read warmer/colder. It is not showing any consistency one ignition cycle to the next.

It was also creeping up 1* at a time with ignition being left on. We might see 5* rise over 5min while ambient temp was actually dropping.



2) We assume RPM should be reading 0 when ignition is cycled yet is it showing >65k rpm. Even when we turn the motor over for 3-5 seconds (coil packs disconnected) RPM does not drop. We tried putting in a 24x base tune and the results were the same.

We also noticed that the provided 6.0 58x crank sensor settings were not correct according to the instructions. I am hoping TJ will register and chime in on this But I believe the tooth setting was 79 in the provided file but we saw it should be 70 online.

None of these changes helped the >65k rpm being shown (65,067 was always displayed).



3) TPS was checked at the MS3 computer via a meter showing 0.7v closed and 4.65v at WOT. This was after trying to calibrate TPS. When closed it was in the 120 range and WOT it was also in the 120 range. I wanted to verify TPS voltage was rising and confirmed.


4) IAT was also showing strange behaviors as well. I didnt keep specifics but it had the same temdancies as the coolant temp, Once ignition cycle IAT was the same as the coolant sensor, next ignition cycle IAT was -80*f.



I verified all 3 grounds are solid, tow on the heads and one to chassis ground which is a round tube frame. The motor and trand are solid mounted to the round tube frame as well.



Any help would be greatly appreciated,

[tjZ06]

Hey all, this is TJ the owner of the rail that Farmtruck is working on. If you're curious, this is the machine:

Potter2.jpg

Potter9.jpg

Potter6.jpg

A little background on the engine combo:

• ~440 CUI
• CBM "Pro-X" Block (basically re-branded RHS)
• GM LS7 Head Castings - Ported
• 13:1 Compression
• Precision Metalcraft Intake
• CBM 105mm TB
• Getting Cam Specs
• 58x/4x (Gen IV) Crank/Cam Triggers
• Obviously no MAF

As Farmtruck mentioned, it was previously on a MEFI (I think it was a 4b...). It ran okay on the MEFI, but it certainly left a lot on the table, especially when going to altitude (Idaho Dunes are 5-6k ft. vs. roughly sea level for Glamis, CA). I was running 110.

We're switching it to the MegaSquirt 3 Pro Evo and utilizing both wideband and flex fuel capability.

I think Farmtruck laid out all of the problems pretty well. It's as if the PCM isn't interpreting any of the sensors properly. I was really thinking a bad ground situation, but Farmtruck chased them all down as well as ran the jumper ground like he described above.

We're really at a loss here, the 65k+ RPM thing is super odd... but perhaps is indicative of a specific problem?

Any help would be greatly, greatly, GREATLY appreciated. We're trying to leave for a sand trip by Wed!

-TJ

[billr]

Post the MSQ and MSl. Yes, the MSL may help even if the engine isn't cranked/running.

[tjZ06]

Post the MSQ and MSl. Yes, the MSL may help even if the engine isn't cranked/running.

Well, some good news:

We just put a new firmware flash on it, and it looks like things are working. Ugh, nearly a full day wasted chasing our tails because the latest firmware here: http://www.msextra.com/downloads/ is not actually the latest version, you need the version here: https://www.ampefi.com/downloads/#firmware which is not super obvious itself. If you just look at it and see 1.3.4, 1.4.0 and 1.5.0 you'd grab 1.5.0 right? Nope, you need to click the link above it, which has no version number or anything and get THAT version. Also, not the version that shipped on the thumb drive w/ the unit.

So, Farmtruck is setting up a very rough base tune and trying to make sure we have wideband and flex fuel reading correctly. Then *maybe* we crank it up...

We'll start logging though so we can post MSQ/L when we run into further issues.

Thank you!

-TJ