Emerald datalogger trace

[nelmo]

So, I have been having starting problems and a misfire on my 2L, NA, FI, Zetec, plenum.

I fired up the Emerald datalogger and I've sent off the trace to Emerald to see if they can see anything but I wondered if anyone on here may be familiar with the datalogger and might see something?

This is what happens when first cranking:

Note how 'InjPW' never gets over 6ms...

Then just before it does start, that trace shoots up:

...and then finally the engine starts:

Anyone know if this is significant?

 

[brumster]

Do you think it's not getting enough fuel to start? Does tickling the throttle help it start? If so, it might need the initial injector prime and/or cranking enrichment increasing. It's hard to say without seeing the entire map to be honest... can you send your .map file to me?

Edited August 3, 2019 by brumster

[nelmo]

No, throttle doesn't seem to make any difference. The whole problem still feels electrical to me... 

I'll try PM you the files (they are Emerald .lgt1 and 2) ...you'll need the Emerald software to view them (free from their website). 

[richyb66]

Dan speaks fluent Emerald.

[nelmo]

Map files attached for all your enjoyment  (you need both for the Emerald software to work).

carRun.lg1 carRun.lg2

[Longboarder]

In the traces above is the pale blue line revs? If so, should it not be continuous? Crank sensor problem?

[nelmo]

Pale blue line is 'InjCorr', whatever that means...

[richyb66]

That's the adjustment it's making to the base map for the cold start. 

[brumster]

The log looks.... weird to me... doesn't make sense... can I just check, in that log, at no point does the engine start right? That's 11 minutes of you trying to start it?

Why does the engine speed slowly creep up over time from 50rpm to 125rpm?! Why is the coolant temperature reading up in the 250+ degrees centigrade ? I don't think it's loaded into my software correctly somehow.... !!

edit: oh wait, I think I know what's going on here. The software ONLY logs the 8 fields YOU decided to record. I was thinking it logged everything, but only displayed the 8 chosen in the software at any one time. I suspect I'm changing fields expecting to see engine RPM instead of coolant temperature, and the software is letting me change the drop-down field, but isn't then actually showing me that - it's showing me coolant temperature still, but represented as engine speed. I think you'll need to re-do the log.

Next time, log :

• Engine speed
• Ign Adv
• Inj Duration
• Throttle Pos
• Coolant Temp
• AFR/Lambda
• Battery
• TPS

Cheers,

Dan

 

 

Edited August 4, 2019 by brumster

[nelmo]

Ah, I didn't think there were others to choose from - I'll have a look next time. 

[nelmo]

As an update, this is what Emerald said about my trace:

You are losing the injector signal, possibly because the rpm signal is dropping out. You need to log the rpm on a channel to check this.

I assume the RPM signal comes from the crank sensor (?) so are they suggesting that could be the problem?

 

[richyb66]

Yes, rpm reference comes from the crank sensor. Is the rev counter showing any strange behaviour? 

[nelmo]

Not that I've noticed but then I haven't been looking at it during the misfire...

Is it common for crank sensors to fail? They're only a magnet, pretty much...

Edited August 6, 2019 by nelmo

[richyb66]

Not uncommon. How old is it? Difficult to test but a new one shouldn't be too expensive. 

[nelmo]

Well, engine only used for 2 years but is from 2004, so sat around for years.

Like you say, only £23 for a new one so ordered it anyway...