I've got a n Elite 1500 and am trying to figure out an issue.
It starts right up, idles for a minute or so, then shuts off.

I'm hoping use the datalogger to figure out what the issue is. The wideband and the fuel pressure gauge seems ok--starting to lean toward an ignition problem.
What channels could I use to try and figure this out?

 

I would use:

​​​​​​Post startup enrichment
Coolant temp fuel enrichment
Air temp fuel enrichment
TPS
RPM
MAP
Engine Run Time
Short term fuel trim, if o2 control is on
And Idle control duty cycle if idle control is on
And wideband O2

You can rig wire the power wire for the wideband to something hot that isn't ignition switched so that you can warm up the sensor and have the wideband go live and log the actual afr during the initial cranking period if its dying before the sensor warms up and the signal goes live to the ecu.

You'll also want to check the sensor and wideband calibrations to make sure they are right. A miscalibrated input can cause the ecu to dump or pull too much fuel when not needed and kill it.

Feel free to post your setup and current ecu file and we can get you sorted. I find that often its something small in the setup that makes initial idle tuning a struggle. Once all is setup right it will fire and idle smooth without too much effort.

If you post the tune file and log from this happening I can take a look.

Skeese

 

Here's a tune file and datalogs from today.

 

you need a lot more channels then that mate since your only logging for 17.9 seconds Id just turn them all on for the time being.

 

Betcha I can solve it with just those. Will look tonight.

 

There is something weird going on here for sure. So for starters, the first thing I noticed is how when you run the logs the fuel load dot NEVER leaves -29.5 inHg, even when the sensor is reading. When the key is on and you are sitting at ambient pressure, you should be getting something really close to a 0.0 PSI reading (which is the standard atmospheric pressure).

BUT for whatever reason, you are pinned to the -29.5 inHg part of the map regardless of pressure input. Why? I do not know...BUT I do think that is the root of the problem. I've had issues before where a snag in not logging fuel pressure combined with having fuel pressure based settings drug me off to an inaccurate part of the map causing over-fueling. I guess the first question is how is your map sensor set up? I don't think its a value-in-table problem for fuel/ignition or anything inbetween. It seems like a setup/interface problem. Where did you get this map and can you list the details of your setup?

Also, what wideband are you using? Have you calibrated the internal table for it? I only ask as its calibrated for an 0-5v signal across 10.0 to 20.0 AFR, and most standard ones are something like 7.4-22.4 and I don't know that I've heard of a 10-20.





Skeese

 

You're viewing manifold pressure not fuel load. Two different parameters. That's why the trace isn't working. The table is fuel load v RPM. Not MAP v RPM. While they're not the same parameter, they should run at the same value. If you log them, you'll notice they vary slightly but MAP is a good enough value to diagnose this situation.

Though there's not a standard wideband calibration. 0-5v = 10-20 is common. AEM uses it and Haltech on their analog output.

 

But when the load type in the fuel tab in the main setup function is set to map then it should reflect the map reading and read something like 0.0 at ambient pressure when the motor isn't running, not -29.5 inHg all the time.

The map I was highlighting does show what the map sensor is reading, but the map - based fuel load in the table is pinned to the lowest point. If you were to show it I bet it would read -29.5.

I dont know too many widebands just personally came across a situation of a miscalibrated table, thought I'd ask since everything else is basemap.

Skeese

 

Fuel load does equal MAP. However, there are two different parameters that can be logged. MAP and fuel load. If you log only MAP, which this guy has done, the tracer will sit at what is effectively 0 while the log is played back because the value represented in the table has not been logged. There is no data. If he had logged fuel load the tracer would move.

That said, take the data that he does have into Data Manager and lay it out in a graph and you'll be able to use it just fine.

In short, there is nothing fishy with what he has as you have stated. Perfectly normal, imperfect set of data.

 

Yeah I'm wrong, I knew that and totally missed the ball here.

So what's that perfectly normal, imperfect set of data say to you? When he said it starts and runs for a minute, that was gracious. It isnt much to work with

Skeese

 

What wideband are you using? Have you verified the timing synch?

If the wideband is correctly calibrated, start pulling fuel in 20% increments until it runs.

 

I'm using an Innovate. Wideband is calibrated. Haven't re-verified timing recently but will do so.
I started retuning. Pulled alot of fuel out of the the low rpm/low load areas of the base map. Idles much better and seems to be running much better at low rpm now. Took it for a 20 minute drive yesterday with no recurrence of the shut off issue. Going to do some more tuning/testing over the next several days.