Suby running erratically then dying...

I don't know who your builder was but 240 seems a bit hot to me, but give us more info. .  

Off the top, I would start with the MAF sensor, cleaning it and the air filter as well if it is K&N or other.  MAF can drive you nuts with some erratic bucking, & stopping at least I have found this.   Getting someone to plug into the ECU to see what happens to the mixtures when it runs is what needs to be done.

hope it helps.

If you have a smart phone and an ELM27(bluetooth OBD dongle) you can figure this out yourself.

If you have an IPhone you'll need the Wifi version, Apple doesn't play well with Bluetooth.

I use the Torque app(free version, with ads). You can set up your screen with all sorts of dials and gauges, monitor fuel flow AFR, temp, MAP, etc. It works real-time with a slight delay, but it works. It also reads codes and can clear them.

$20 bucks or so.

240 degrees? I'd say you have air in your cooling system. Not good to run like that, you'll warp your heads and cause head gasket/coolant leaks.

Thanks for the info, guys.  The Boys From Breman built and installed the engine and it's been running flawlessly.I have a code reader but I can't get it or any other reader to function.  I tried cleaning OBD the contacts on both the male and female ends with the spray can of cleaner to no avail.  I have Apple products so I can't use the PC apps and I'm having a good day when I can figure how to power on my MacBook Air. I have VDO gauges and it's been suggested that I have the incorrect sending unit so I'm going to switch sending units.  I also have a digital gauge to install that came from Down Under that I am in the process of installing. It's interesting that the skipping, stalling, and dying happened at the same time that my OBD went out. Carey said that he was going to have Mike stop by when he comes to Atlanta again to pick up some parts from Chuck Beck...hopefully sometime within the next month or so.  Carey has been great in giving me suggestions.

Meade

Meade,  The idiot gauge in the vdo new guages is not that precise.  I installed a temp guage for head temp on my subie and it also does my tranny temp.  After running it for a while I now know the range of operating temperatures that different driving, outside temp and load gives for my car. It also has a out of range alarm.

It is kind of a no brainer to install as well, you just have to find a bolt on the cylinder head and one on the tranny and run it to the controller under the dash.

https://engineguard.com.au

I have the engineguard as well, and as luck would have it, Someone misplaced the block sensor.  I have the water temp sensor as well and I am REALLY not understanding the installation of that part.

Meade

That sensor goes into the water line which for me was a pain so I used 2 contact sensors only.

So you didn't use the water as a source for temp? Or you used a different type of sensor to check the water temp. Can you recommend a sensor to use for the oil/block temp? Thanks for your advice, Meade

Meade I should mention that if the engine throws a code or goes into limp mode you can turn the key off then on then Off then On a few times and it should clear the code and you should be able to get going agaiin until the next episode happens.

I use a wifi and Carista ODB sensor to do basic read and clear functions.

On the sensor front, if you goto their site you will see that they have a one or two sensor versions.  You can get the contact sensor from them, which simply bolts to the head as I mentioned.  It is not as accurate as the INSIDE THE PIPE water sensor that you must have but it is a lot less work and hassle to install.  

At least what it gives you is essentially cylinder head temperature which is all that I was worried about as you can extrapolate the water to be lower IMO.  I might be wrong on the specifics here but it sure beats the VDO idiot needle.

Here is the sensor in a spare hole in the head.

Here is the sensor in the Tranny side bolt ... it takes a long time for the tranny 75-90 Swepco 202 being used to get warm compared to the engine head temperature.

display

Hey Ray, they do sell bolts in different lengths at the hardware stores.

They do but I like the Herman Munster style bolts )

Bad coil pack is a possibility.

I was thinking about that too, Ed.  Also a bad fuel pump and a bad gas filter.

meade

@Meade posted:

I was thinking about that too, Ed.  Also a bad fuel pump and a bad gas filter.

meade

95% of fuel problems are ignition. Happy hunting.

I thought I had i as I pulled it solved this morning when I discovered the ignition switch screw....

was a littlebitloose.... But just as I pulled into the subdivision,;;it started back misfiring again.Meade

Certainly sounds like a coil that is going bad and dosn't like to be hot.

I'll put on my coveralls and se if I can discover the location of the coil.

FYI, the subie has individual coil packs ... one per spark plug

I just checked youtube and a mechanic eluded to the MAF as being a problem on the car he was working; a Hyundai.

Hi If you look at the K&N you can see the MAF in black on the metal aluminum sleeve on my car. I usually unplug it and loosen the band clamps and take it off.  I then use either MAF cleaner or non chlorinated brake fluid to gently spray to clean it then I use a bit of compressed air GENTLY to dry and wait till it is completely dry when you plug it in.  

BTW great time to do the K&N and the MAF at the same time is off season at at all oil changes.  Hope you find it.  BTW, Sx my car would buck at 4k rpm when hot. no fun. Dx MAF dirty, then MAF deffective once.

+1 on MAF cleaner.

Thanks Ed and Ray; I had some cleaner but threw it away; I'll get another can tomorrow.

Meade

Don't over oil the filter if you're running a K&N (or any oiled air filter) and you have a hot wire MAF. Excess oil from the filter can get on the wire and cause issues.  A normally oiled filter won't cause any problems, but I've seen a few folks get caught out by the if-a-little-is good-then-more-is-better approach to oiling the filter.  Also, make sure it's all dry before you start the car or the same thing will happen.  You're lucky you have a CANBUS port to trouble shoot. It should tell you if there are sensor issues or the cylinder with misfire issues.  But if it's not saying anything specific then you can go down the list.

- All sensors are functioning properly (there are lots of them)

-All connections are good and grounds are good (including ignition switch and starter circuit wiring)

-Plugs and plug wires are all good

-Coil is good (single cam Subies usually have 1 coil, dual cam may have coil on plug)

-Wiring harnesses for coil(s), injectors ,sensors, and ECU are good

-ECU is good (if it's bad replace the alternator as well. Voltage spikes kill many an ECU)

-Voltage supply to ECU is consistent and correct (See above, you might find it before it fries your ECU)

-Drive by wire accelerator pedal should be checked for proper signal/function if you're running the Subaru ECU, and make sure that it's wiring is secure and complete.

-Valve adjustments are correct (Single cam Subies have manual valve lash adjusters, they just don't typically need much attention.  Dual cams usually have hydraulic lifters.)

-Fuel supply is good (pressure, consistency of flow, filter clean, etc.) and good over time (an overheated fuel pump failing can be a thing)

-High idle or idle bypass solenoid working as intended if so equipped.

-Fuel injectors are functioning properly (You can't fix a wonky fuel injector with anything that comes in a can.  If they are gummed up, or intermittently working, pull them and send them out to be rebuilt.)

Welcome to the world of EFI.  It's much easier to live with most of the time.  But when something goes wrong it's no different that carbs and ignition points.  Go through your check list one logical step at a time until you find the b***ard that's causing all your pain.

Well Michael thanks for the post, my subie tech hardly oils his K&N's he finds the over oiling a problem with a lot of cars.

@JMM (Michael) posted:

-All connections are good and grounds are good (including ignition switch and starter circuit wiring)

-ECU is good (if it's bad replace the alternator as well. Voltage spikes kill many an ECU)

-Voltage supply to ECU is consistent and correct (See above, you might find it before it fries your ECU)

I've had to add extra grounds on several Subarus. I usually add an extra ground strap from the engine block to the negative battery post, and likewise from the alternator housing to the battery ground post.

It seems to stabilize the voltage and lowers the voltage difference between the alternator and what you read at the battery. FYI, if there is more than 0.1 volt difference between the alternator and the positive battery post voltage, replace those wires that show too much voltage drop.

Whew!!!a bunch tech language, about a half of which I do not unnerstan......but I appreciate...

meade