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padgett 10-22-2012 11:20 AM

Smokey Mountains and Electronics (long)
From what I have seen so far (e.g. 8.4" display in Dart), it is still far less that what I have already. Have seen mention of using the Southern Pacific Railway Internal Network and Telecommunications and all I can say was that my company cell phone rarely had service around Franklin but since my hotspot and personal cell use "Americas Largest Most Reliable..." every time needed, service was there.

For most of the trip, I just had my 7" dash display monitoring the engine with Torque - did find a direct correlation between the OAT and IAT/Coolant temp which leads me to think the V6 radiator even with the towing package is undersized (my other cars lock within 5 degrees F of the thermostat opening regardless of local ambient).

This indicates that the Pentastar head issue is temperature related and the incidence of ticking will probably drop off now that cooler weather is back...until next summer. Makes me want a bigger radiator and a CAI.

Cannot overemphasize the value of proper instrumentation but suspect most EVICs are on the MPH (or KPH) readout and not coolant temp - the gauge never seems to move once warmed up.

Meanwhile, I am using my radio more and more just as a aux input, really just need onboard amp and speakers (and maybe Uconnect), everything else stays with me.

I don't think the auto mfrs have understood this yet, that onboard maps and such are nice but the comm part is an individual matter & included with smart phones today.

BTW has anyone noticed that the 8.4 is really a 7" widescreen with top and bottom borders to fit a DIN slot ? Most tablets already have buttons and such outside the screen.

Of course we are still in a transition period from land lines to mobile everything but I expect a division to take place with a reduced reliance to what is on board and more on the personal devices. That way the vehicle personality is matched to the driver and passengers: Read the cell phone and move the seat/wheel/HVAC/entertainment to the proper position ? We are soooo close.

My trip to the Smokies just pointed out the strengths and the weaknesses. That I needed to mount my own Android device/screen was an anoyance but did not cost much. Biggest issue is that lacking a composite input to Android means I have to use a seperate back up camera display.

Strength is that I was always in touch. Need to connect to Amazon while in a parking garage: No Problem. Find the 'Gators kickoff time while on the Interstate ? Same-Same. Only issue is that some things should not be done by a left lane driver & left to the navigator which requires a technologically apt navigator.

Summing up, the total capability is incredible and by selecting the right provider, "anytime/anywhere". Technology is colliding, often untidily but phone/web/text/tv all is really the same, just today I need multple devices. Tomorrow it will all clip on my belt (actually the Proclaim is almost there).

At the same time the vehicle on-board systems will decline in importance, they cannot (at least as designed currently) be flexible enough to accomodate everything a belt device can. A linked touchscreen with display of personal device and rear view camera plus handsfree & amp & speakers is all that the vehicle needs.

Finally, people already have too many subscriptions. This will change to a single provider of telecom services.

ps The Android hot spot works fine with an iPad, it is all really the same.

Suther 10-22-2012 05:42 PM

Thanks a lot for all the effort and the information. Always like to read your posts as they are always educating.

That brings me to my question in trying to understand the whole misfire story. Disclaimer; I am an electrical engineer who doesn't have a clue about engine design but discovered his passion on doing more himself on cars.

If understood correct a misfire is a non ignition, right? Caused be to lean gas-air mixture or missing spark. So reasons for this would be lack of or reduced injection, open exhaust valves, bad gas, defect spark plugs, cables or coils. Sure there is more to it.
So, how can the cooling temp influence a misfire? Thinned out oxygen due to the air intake temperature? Wouldn't hat mean the PCM is programmed to the edge?

Thanks ahead for the answer.

padgett 10-22-2012 08:33 PM

Re: Smokey Mountains and Electronics (long)
Pehaps "misfire" is a misnomer but that is what a code P030x is called and the CEL usually results from a P0302 or P0304.

What it really means is that the engine speed (rpm) is not constant and it is slowing a little when that paticular cyl is supposed to fire.

So a "misfire" is any time the cyl does not fire properly and that can include pre-ignition (could go into a long dissetation on maximun cylinder pressure ad such. Won't).

Now there have been a lot of tidbits floating around about the Pentastar problem but we had a pretty hot summer and the issue was first noticed in June. Burned valves and bad valve guides were mentioned and my long experience with engine failures (including burning the #2 valves in an XK-150S Jag a long time ago) point to overheating/over lean/detonation as a cause.

Another data point is that Wranglers seem to have more of a problem than the GC. Mention is made of temps near the red line as common, they weigh over 4000 lbs, and have a 3.73 rear gear which means they wind pretty tight on the Interstate plus tend to do more rock climbing. Note that the rated MPG is less than the GC. More gas means more heat.

So yes I suspect that when the truth finally come out we will find that "something" in the original (444) head design makes #2 and #4 run either hotter or leaner or maybe both. Under extreme heat conditions (e.q. over 100F), heavy load, maybe 85 octane gas (common at high altitudes).

Going a bit off the wall, perhaps pure gasoline rather than 10% ethanol will run just a bit hotter. Lotsa heat of vaporization in alcohol.

Will wager the incidence is dropping and will return with 100F temperatures. But until the root cause leaks or someone who understands flow design can compare both old and new heads (may just be an additional/enlarged coolant passage).

Meanwhile I will probably add the factory CAI when it becomes available just to reduce the charge temp a bit. Nothing to do with sound or power, just longetivity.

Suther 10-23-2012 04:05 PM

Re: Smokey Mountains and Electronics (long)
Thanks a lot for the explanation.

Pre-auto ignition and overheating to cause a sensor trigger as you described would make a lot sense to me. So basically the "Misfire" is any unregularity in the rpms in correlation with the ignition timing of an individual cylinder.

Related to the Pentastar #2 misfire, I think there are too many subjective statements to properly determine a cause - effect.
I agree that the summer - misfire relation is visible, but that can also mean that the median of the involved engines hit the market, or more people could post because they were on vacation:D

Anyway, how could we rule out variables? Wouldn't Ethanol 85 with its OI of 105 prevent auto ignition better? Not sure what the temps would be though.

I am not sure if a CAI would actually decrease the intake temp, as most of them look like they would suck the air more from the engine bay then from externally.

padgett 10-23-2012 08:51 PM

Re: Smokey Mountains and Electronics (long)
Well I am just looking for the tube to get rid of the furnaces in the stock unit. I may buy the Mopar unit just for the tube, the stock air cleaner and intake over the rad shroud looks pretty good to me.What bothers me is that the thermostat appears to be a 195F and below 65F the coolant sits on 197-199F and IAT is under 90F. At higher ambient it goes over 200 (and just saw 208F coming home this evening).So the car is designed to run fine at the lower temps and I just need to lock it there. Now I am suspecting that the radiator is too small, I have no problem keeping my GM 3800s under 190F. Just looked and the Reatta radiator is about 480 sq in and the Heep is over 550 so it is not just area. Suspect I may need to bring the fan in earlier & mybe try without the partial belly pan..

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