Intermittent Issue (Car dying)
 

Ok, so I swapped out my fuel pump and "fixed" (maybe, hence the air quotes) the A/C in my car and now I'm having weird intermittent issues that don't make any sense.

Specifically, randomly after about 3 minutes or so, my car will just lose power and die, and there's not a damn thing I can do about it. Throttle does nothing. It lasts for a few seconds, and even power cycling doesn't fix it. I have to wait a bit, crank for a bit, stop, then start it again and boom. It acts like nothing ever happened. This is consistently happening about every 3-5 minutes. My first thought is fuel pump as I just installed one, but I purchased the DW200 from Supermiata and I didn't think those were prone to failure. However, my unit had clearly been opened before (even though I was supposed to be buying a "new" product), so I really have no clue. (edit: pretty sure this is the pump. Swapping back to my Walbro 255 to see if that fixes it)

I've got a data log of the event happening in my driveway. It doesn't seem to matter what I'm doing as just leaving it idling can cause it to die, so I'm at a loss. The only settings I was playing with were idle related settings to get the A/C to idle up properly, but that's proving to be a nightmare in itself as my A/C condenser doesn't seem to be generating a consistent load at all.

I just took a generic datalog of whatever was offered. I'm still learning my way around megasquirt, so if there's a way I can improve my logs to capture whatever data is needed for this, let me know. Looking at the raw data, there doesn't seem to be much here to my nooby eyes.

Alright, now this is definitely outside the realm of ECU/tuning, as I do believe it's the new pump issue. Reached out to supermiata, and was just told a blanket "prove it" response, which is fair. Now I'm stuck trying to figure out how to "prove it" when this seems like a fairly straightforward cause/effect. Swapped fuel pumps and no other fueling changes, and now I'm running into fueling issues. I'm going to swap back to my noisy Walbro 255 and see if this goes away.

You posted a composite log which doesn't really tell us anything.

Yeah, I know it doesn't say anything useful. I said that. I also asked what kind of log I could provide would be useful.

That isn't exactly what you asked. Based on your original post I made the assumption you accidentally posted a composite log instead of a datalog and simply needed to post the correct file. I didn't realize you had done so little to help yourself that you didn't know the difference between a datalog and a composite log.

It's a learning curve. A standard datalog will be what we need to see.

Check your Underwood fuse block and main relay. Mine actually had heated up at a main relay terminal and melted the plastic surrounding it. I rewired the pump with a separate relay and haven't had the issue since.

May or may not be part of your issue. Could be,pump connections too.

Sorry, I was a bit on edge as my car that I felt I was just a few minor things away from being "right" suddenly became undriveable. I've ordered a replacement relay, and am strongly considering the fuel relay rewire.

Knowledgeable people are offering to take the time to look at a datalog to confirm the assumptions you've made, but instead of posting one you've decided to throw parts at the issue.

I'm baffled.

Because I pulled my main relay out, tested the coil wire for resistance and found it did not even complete a circuit. I can no longer start the car and generate a log until the replacement part arrives.

An appropriate jumper could be used temporarily to confirm your relay diagnosis.

I think it's pretty rare for a coil to fail in a relay. Usually the current carrying contacts fail.

I'd be curious to see the charging voltage when the car is acting up.
I know it will be in the log, but hooking up your voltmeter to B+ and ground and observing is pretty easy.

A pretty remote possibility, but one of the diodes may have fried in your alternator.
Just a thought.

Do you have a melted crank angle sensor. wire. It's standard path puts it pretty close to a hot turbo manifold. Mine kept doing this because heat would raise resistance to wire to point it would not see crank angle and die. Once car cooled down I could start it again.

I think your turbo-encabulator isn't correcting side-fumbles :/ replace the unit.

Seriously post some logs mate, we have absolutely no idea what is going on if you don't.

If you post logs we might be able to say, hey look your fuel stopped at the same time, because your crank signal stopped coming through.

Jump your relay or just hard wire your pump to 12v and get us a log.