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Apr
9
comment do all quattros have shafts connecting front and rear axles
Could you post a picture of what you're seeing? We would certainly expect to see a driveshaft running to the aft end of the car: fotos.autozeitung.de/1024x768/images/bildergalerie/2009/06/…
Apr
8
comment Overheating & coolant loss in 1998 Subaru Outback
+1 for an excellent write-up
Apr
3
comment Use of Neutral Gear in Automatic Transmission
@Jesse, yes, you're correct. At the same time, so is Rory. If you're shifting to park, you're almost certainly motionless (or about to learn a valuable lesson). So you're going to shift from D to N to R to P.
Mar
29
comment What are the benefits of premium (high octane) petrol?
What's missing from your remark about "power adder"s is why they require higher octane. In the next bullet, you imply that any additional power will require higher octane. That isn't the case: a better intake and exhaust on NA cars will often improve power without impact on octane requirements. As written, this answer is incomplete, bordering on incorrect.
Mar
28
comment What are the benefits of premium (high octane) petrol?
"But due to the power adder they will require a higher octane": this is a specific place where compression and temperature are both important. The compression ratio on the Fiat Abarth is apparently 9.8:1 (higher than my old Mustang V8) with a peak boost of 18.1 psi. That means that without boost, the car should be able to handle regular gas. As higher temperature boost is added, low octane gas will become problematic quickly.
Mar
27
comment What are the benefits of premium (high octane) petrol?
This answer is also missing discussion of temperature which is just as bad as compression in an ideal gas law sense.
Mar
25
comment gas pedal only works when really depressed
For slack cable, might want to point out that max acceleration will be WAY down.
Mar
25
comment What could cause my Honda Civic to not start? And how can I address the issue?
@BiffMaGriff, congrats!
Mar
24
comment Audi A5 sat nav through SD card
@theUg, I'd rather let other members of the community make that assessment. We have quite a few active users now: what do you guys think?
Mar
22
comment Audi A5 sat nav through SD card
Welcome to the site! It is not clear from this question what mechanical problem you are trying to solve.
Mar
20
comment Why does my gas not fill all the way?
Yes - could confirm that it's a bad reading by checking mileage. Is the OP still getting a full tank's worth of driving range?
Mar
19
comment Does accelerating faster worsen fuel efficiency?
BSFC gives you information about your engine at a steady state, not during acceleration at different throttle positions with varying tuning parameters. Fuel consumption is easily measured using the OBD II port. Rabbit starts are less efficient than gradual acceleration.
Mar
18
comment What happens if I drive without antifreeze in my car?
Clarifying the "empty": was the entire system empty or just the overflow tank? There's a lot more coolant in the system (normally) than is found in the white plastic expansion tank. Did you remove the radiator cap and check to see if it were bone dry? Said another way, how much fluid did you have to put in to fill it back up? If it wasn't more than five quarts / liters, then it wasn't empty.
Mar
18
comment What happens if I drive without antifreeze in my car?
To clarify, were you low on coolant or at zero coolant? Those are two totally different situations. The first is potentially a don't care in the middle of winter, the second is potentially fatal for the vehicle.
Mar
18
comment Does accelerating faster worsen fuel efficiency?
"(excluding wind, friction and rolling resistance)." Those exclusions remove all of the real world concerns of this question. This isn't an abstract physics problem. BSFC is useful to determine the most efficient engine speed on an engine stand. It does not directly translate to the most efficient speed over ground (frictional losses are important). It gives you no information about efficient acceleration as the loads and fuel consumption profiles vary wildly (e.g., increased fuel added to cool the charge under boost).
Mar
16
comment 2007 prius premium gas or not?
@Larry, I'm not stipulating that the units fail before the warranty period. Warranty periods and the associated engineering problems are an exercise in expected value, though. The manufacturer is trying to minimize the expected cost to them: (probability of failure before X miles * cost of replacement) + (probability of working fine after X miles * cost of required engineering). The whole issue is a little muddled since batteries don't fall off a failure cliff. They degrade for a while before the customer really notices (which might not be the case for this OP).
Mar
15
comment 2007 prius premium gas or not?
@Larry, I'll bet it's not most batteries that last much longer considering how warranty duration calculations are done. Regardless, these batteries are older. They won't have the efficiency that they did when new. On the third hand (!), it's the driver's car: she has to make the call what works best.
Mar
15
comment What modifications need to be made to an engine to enable higher safe RPMs?
Moving parts => steady state motion plus torques plus accelerations plus jerk (the first derivative of acceleration). Everything gets much worse much faster as rpm increases. The conversion of linear to rotational energy and back again, the stresses... urgh. The mind boggles.
Mar
14
comment What is recommended way to fix rear station wagon windshield wiper?
See Rory's answer below: a picture of the spring part of the arm will make it clear if that's the issue.
Mar
14
comment What is recommended way to fix rear station wagon windshield wiper?
Could you add a picture? It would be more clear about what's currently bent, zip-tied, etc.