EFI Learning Curve

[tmsmini]

Drove the car all last week without issue, then on Saturday it dies at stops signs a few times.
Today temps in the low 40s, no problems on the way to work. It is the inconsistency that is frustrating.

I really need to understand the carburetor dynamics when you come to a stop and lift off. With a mechanical carb, I sort of understand what is happening by watching vacuum.
With an electronic carb it is just doing what it is told to do. It seems there would be more control with a MAP or MAF sensor, but that is not what SC has. The ECU has provisions but not used in the kits.

I found a good site with animated GIFs that went over the stages of vaccum for a carb, but cannot seem to find it now. After all the engine is just an inefficient air pump...

[tmsmini]

Just an update...
Getting this car back into shape is taking its toll.
A month ago we had about 500 miles on the new engine, so it was time for a re-torque and valve adjustment.
I found a valve sitting at an angle in the head when I went to do the adjustment. So off with the head and off to Seven for repair.

Got it back quickly, reassembled, started it up, let it idle for a bit, shut it off and went about cleaning up the garage.
When I went to start it again, it would not start. Checked everything and found nothing unusual.

After many rounds of non-starting partial combustion, swapping parts(and a couple of weeks during the holidays), I figured the plugs could use a change, also changed plug wires.

It is now starting and running, but I do not really know what the cause of the non-starting condition was.

So I can now get back to fine tuning the injection as I planned to a month ago.

I usually add a second ground strap and this car does not have one yet, so I need to add that. Maybe the ground though the dogbone attachment was not making good contact

[John Gervais]

I've never really been a fan of the dog-bone ground strap arrangement, though I still use it.  I don't like that the strap connects to the plate on the bulkhead.

It sounds like you've probably thought of everything I'd suggest (cap/rotor/ground, HT leads, plugs, coil connections and your fuse block is probably clean for the actual switch connections), so I'll only wonder as to the cause of the bent valve?

[MtyMous]

Gosh. I'm watching this thread like a hawk. I'm going to be picking your brain for months when the time comes to run mine in.

[tmsmini]

So no rain yesterday. I added the second ground strap. My wife had driven it for a couple of days last week with out incident, so I went for a 25 mile or so drive.
Nice twisties, but being Sunday there was a bit of traffic and then on the freeway to home. Lots of starts and stops at lights and stop signs, good high speed climb up a grade and no issues.

Not sure if I will ever know what the problem was/is.

It did have a few flat spots at speed when accelerating, so a trip to a dyno would help. I will do some more seat of the pants tuning with the Innovate.
I did find one gotcha... as Nick used Russell Performance connectors they have a threaded retaining cap to keep the fitting secure. One of them came loose and they do not sell replacements, you have to buy the complete fitting. After looking at the directions, they suggest using Loctite if you need to...
Terry

[tmsmini]

Found that Oreilly can order the Russell Performance fitting and deliver  in 24 hours. Summit also has them but shipping can get expensive.

[tmsmini]

Renee, my wife, let me drive the Traveller today(It is her car). It seems any initial issues are cleared up. Drove well and with no issues at stop signs.
Not sure when the bent valve occurred, but it seemed to be severely impacting running. I am guessing with a feedback loop, the AFR was all over the place and the base settings were also off.

I have a good hill on the way to work and it seems there is a flat spot between 3700 and 4000, so more tuning is needed at this point. I may add the wideband option to the setup so that AFR can be recorded natively in the SX Tune software instead of using the innovate. It will make it easier to correlate data, instead of trying to match up separate logs.

[tmsmini]

I am beginning to think that a system with out an idle air control valve will struggle under certain conditions.
Yesterday with early morning temps in the upper 30s, the car died at stop signs again. On the way home with temps in the mid 50s, she had no problems.

I am not sure I fully understand the operation of an IAC valve, but it certainly can do what it is named. There may be some additional temp enrichment that may help, but it starts fine.
Terry

[tmsmini]

Dragging this one back up as a public service announcement...
Specialist Components customer service leaves a lot to be desired.

I was contacted privately by members of a UK forum and informed that there are similar stories of woe...

I did get a wide band from them online, but no responses to my questions on making use of the wide band in SX-Tune.

The car runs OK at this point except for dying at stop signs for 20 minutes from a cold start, not practical when both my wife and I drive our Minis daily and have a number of stop signs in the first 10-15 minutes...

A few flat spots in the fuel map, but those could probably be resolved with a working wideband.
Terry