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YOUR RESEARCHDon't sweat the heat...here's some graph data showing..
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Use 6th is
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The only time I use 6th is when I'm actually going somewhere.
Don't sweat the heat...here's some graph data showing..
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Leading evidence: 'Use 6th is' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Repair shop getting estimate as i type' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
Car back in Livermore at body/repair shop getting estimate as I type.
Don't sweat the heat...here's some graph data showing..
Run above
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Suggestion
I think these are data "points" not real time rmp logs - if I draw a line at 3k rpm, you only have about 20% of your run above that line.
Don't sweat the heat...here's some graph data showing..
Run instance the boxster
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Suggestion · Original poster
If I run for instance the Boxster with the A/C off in hot weather and in slow traffic conditions, I will see coolant temperature climb to the point the fans come on then the coolant temperature drop as fans remove heat from coolant.
Don't sweat the heat...here's some graph data showing..
Run instance the boxster
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Suggestion · Original poster
If I run for instance the Boxster with the A/C off in hot weather and in slow traffic conditions, I will see coolant temperature climb to the point the fans come on then the coolant temperature drop as fans remove heat from coolant.
Don't sweat the heat...here's some graph data showing..
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25 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
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Generation: 20261026T105141Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
what my 03 Turbo did in Sunday's 111F heat coming back to Livermore from Stanford Concourse.
Look at coolant temperature graph and intake air temperature graph. Even in Palo Alto car's OBC showed 100F and on way east OBC temp climbed to and at one point for several miles was at 111F. Then it got cold. Dropped to 107F.
Sincerely,
Macster.
The only time my coolant temps get up too high for my comfort are when the car is not moving, in bumper to bumper traffic, for a long time (I'm talking real, 2 to 3mph stuff). Otherwise, pretty close to 180 mark.
Moving high volumes of air over the radiators (instead of hot exhaust from the car in front of you) is the key! Even 30 seconds at 60 mph is enough to dramatically reduce temps on a hot car. Opening the engine lid also helps a little
CarChip. Connects to car's OBD connector and requests OBD data (speed, rpm, coolant temp, etc.) and logs it to non-volatile memory for later retrieval. My employer makes/sells this device into the consumer and fleet markets.
Um, about those colored lines... Just keeping up with traffic.
Sincerely,
Macster.
I have one of these and it's fantastic. I use it for all of my cars. It's been invaluable diagnosing issues on my wife's Accord.
I have no relationship to Macster or Davis engineering. Oddly enough I won my carchip in a contest at autogeek.net but, it's been a great product.
Remember, unless you are reading the coolant sensor directly, you are NOT reading the actual coolant temperature. It is extremely unlikely (if not impossible) that your coolant temperature remained in the narrow band indicated. The OBD reading is smoothed by the computer. Additionally, there is substantial lag in the temperature sensor.
So what purpose does the OBD2 coolant temp data serve if it not valid data as you seem to suggest?
I think smoothed not smoothed, lag or no lag, its a clear trend that the temp is stable in a variety of different driving scenarios. Other than that, you're simply splitting hairs for a street driven car.
and convertered to temperature. So one is not reading the actual sensor voltage but the temperature the Ecu derived from the voltage.
However, I think this value is well valid. I've observed -- used an OBD code reader/data viewer observing OBD data in real time -- many times in the various cars I've owned since OBD II became standard and seen the coolant temperature reach the trigger point when the radiator fans should come on and they do. They go off when the coolant temperature drops below the fan off temperature threshold.
If I run for instance the Boxster with the A/C off in hot weather and in slow traffic conditions, I will see coolant temperature climb to the point the fans come on then the coolant temperature drop as fans remove heat from coolant. When coolant temperature drops below fan off threshold of course the fans shut off. The coolant temperature slowly begins to climb again if the same driving conditions prevail and the process repeats itself.
The coolant temperature data very real time and not smoothed any significant amount if at all.
Other OBD data: ignition timing advance, MAF air flow, O2 sensor voltages, short term/long term fuel trims, etc. all appear reasonable, believeable and up to date, real time, as near as I can tell.
I think the coolant temperature reading obtained from the Ecu is close enough to reality to be very meaningful and useful.
Sincerely,
Macster.
so which years have OBD and when did OBDII replace it ? - I see some of these are not very expensive and might be fun to record certain data for later review.
your rmp was below 3k while traveling at above 70 mph for a long stretch...for me I tend to keep in lower gear to keep the r's up a bit - sometimes I run down the freeway in 4th and as long as I dont go over 75 I just keep it there....I almost never hit 6th gear (unless I am having one of those solid red/blue line moments)
I think these are data "points" not real time rmp logs - if I draw a line at 3k rpm, you only have about 20% of your run above that line. I assume that is either because it doesnt record real time or you just dont rev the motor thru the gears as we would see more spikes from shifting - right ?
I tend to drive this way as well when moving about town on the interstates. The only time I use 6th is when I'm actually going somewhere. Around town, there are far too many passes to be made to simply cruise in 6th
Macsters car is a 996 Turbo...... boatloads of torque under 3k rpm.......
several reasons... (none of them based on any real data to support them
)
for me having the r's higher means when I let off a little in light traffic the speed comes off quicker, so less brakes. I also like it for the instant power when I get a second to give it a little extra fuel. I think (again no data) that these engine prefer to spin faster than to put the torque loads on them at low rpm's - it "feels" faster
I believe having the motor spinning faster puts less stress on the motor than lugging it around...(not suggesting the data above is "lugging" the motor) its just what I think......
this could hurt
Device can't continue to record "after" trip ends. Once trip ends data recording comes to a halt and trip ends when car stopped and engine shut off.
If engine cooled down properly engine coolant should not rise much to be of any concern.
Where there can be "trouble" is if car taken off track "hot" and engine shut down with no time to shed substantial head load that has built up.
As this heat migrates from engine components to coolant coolant temp can rise dramatically though this might be reflected by coolant temp since coolant not flowing past sensor.
Sincerely,
Macster.
ok. The data obtained from my 03 Turbo and engine has boatloads of torque at 3000rpms. But even with Turbo I sometimes shift down to 5th even 4th of climbing a steep grade like I was driving up 50 from Sac. Ca to Tahoe/Carson City, et al the other day.
Data is real time, well all data but speed data is sampled at 5 second intervals. Speed data sampled at 1 second intervals.
This may be why rpms don't quite follow speed.
OBD I came before OBD II -- sorry to state the obvious -- but I don't know when OBD I was required, what year it first appeared. I know OBD II required starting in 1996 (USA cars and light duty trucks).
Sincerely,
Macster.
Yes, I agree. The A/D converter itself has a granularity/resolution limitation, which clearly shows in the graphs.
I don't see no filtering (or "smoothing" per layman's terms), I doubt the ECU has some sort of DSP in place just for coolant temps -- why would it?
I'm ordering one of those!
suffered some damage. Looks bad of course, but nothing major. Pic on the 996 Turbo section in a message I posted the other day.
Car back in Livermore at body/repair shop getting estimate as I type.
I'm in Limon CO ready to head to Denver airport return rental car and see about getting flight to Oakland.
Sincerely,
Macster.
samples those data every 5 seconds and in the intervening seconds the software just fills in the time/samples with the real sample taken at the 5 seconde interval.
Well, something's got to have an AD/converter cause coolant sensor emits voltage, not digital signal. Ecu probably has many AD/C present. Microprocessor in CarChip has at least one with 8 (or 16? I forget number now and can't look it up) channels.
AD/C common on microprocessors and especially Ecus cause so many inputs to Ecu are in voltages: coolant temp, air temp, O2 sensors, etc.
Sincerely,
Macster.
of Flat6Engineering has I think) and have recorded interesting data.
The device I was using is not general purpose/expandable data logger but mainly geared towards trip recognition and data logging associated with trips, speed mainly. OBD II data logging added feature to help fleet customers monitor vehicle population health and provide some diagnostics capabilites when (if) check engine light ever comes on.
Sincerely,
Macster.
This is a source reference. Confirm exact model applicability in the original material.
