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seen Jun 9 at 4:17

Mar
5
awarded  Yearling
Feb
13
awarded  Notable Question
Nov
27
comment Is a bad battery bad for other components too?
You've really picked the wrong answer here.
Nov
27
comment Is a bad battery bad for other components too?
Also: resistance increases with temperature.
Nov
27
comment Is a bad battery bad for other components too?
-1 "The lower the voltage the higher the current draw" This is just wrong. Unfortunately, a lot of people have used 'P=V*I' and got it into their heads that there's some higher authority that keeps power fixed. It's only true for a motor when it's coupled to a load that increases at low rpm.
Nov
27
comment Is a bad battery bad for other components too?
Also: I have no idea what's going on in the last paragraph. Stall current is simply V/R. After that it's useful to know that current draw is proportional to torque, so unless you think that output torque is higher when starting on a weak battery, the current draw will necessarily be lower. It's true that you can kill a motor by giving it low voltage by keeping it close to stall for longer that it was designed. Whether it's a problem depends on how long the OP means by 'a few turns'. Failure would be from overheated windings, so the fact that this only occurs on cold days helps.
Nov
27
comment Is a bad battery bad for other components too?
-1, I don't buy this. For the alternator any increase in charging current would be marginal, or negative. Sure the open circuit voltage is lower with a weak battery, but remember that the increased series resistance for a weak battery applies when charging as well as discharging. At any rate, the draw will be less than charging current of a fresh but discharged battery, so it'll be well within the design limits of the alternator. No reason for concern.
Nov
26
comment Could less than optimal battery charge prevent starter bendix drive from engaging flywheel?
If there's no solenoid on the starter I have no idea. On every starter that I've dealt with there's a solenoid on the starter itself that both pushes the pinion into the flywheel teeth and closes the circuit for the starter itself. The sprag clutch is in there to stop the starter from overrunning (and charging the battery) once the engine starts. It kind of sounds like this is the kind of starter cinelli is talking about, but I'd had to question his/her advice on so little information. I've never dealt with or seen a Bendix before--good luck.
Nov
25
comment Could less than optimal battery charge prevent starter bendix drive from engaging flywheel?
You're mentioning a solenoid. Are you sure it's a bendix drive? It sounds a lot more like a faulty sprag clutch on a regular starter.
Nov
24
comment Failed emissions - high lambda, low HC and CO
You're right. I just realized that I got my lambda backwards (or rather confused it for phi). I've deleted my answer. Low CO should have been a clue... Embarrassing!
Nov
24
awarded  Scholar
Nov
24
accepted Effect of loss of fuel tank vapours on mileage
Nov
24
answered Effect of loss of fuel tank vapours on mileage
Nov
24
comment Effect of loss of fuel tank vapours on mileage
Also: I assume that when you said '... will not be able to determine air density...' you meant that MAP based systems won't be able to account for the added fuel content of the charge. Old MAP based cars had the EVAP system ported into a just-off-idle spot in the throttle body, so you sucked unmetered fuel vapours whenever you'd tip-in from idle. The enrichment wasn't a problem under the emissions regulations of the time. Newer systems added solenoids and ways of modeling the enrichment.
Nov
24
comment Effect of loss of fuel tank vapours on mileage
The conclusion about the catalytic converter is complete bunk. You're completely ignoring the fact that the engine will run in closed loop almost all of the time, and when it's not running closed loop it's running intentionally rich. Any vacuum leak on a MAF based system will result in the engine running leaner than expected in open-loop. Whether it's enough to damage the engine depends on the size of the leak, but it's unlikely to be large at WOT--the air would much rather come in through the gaping throttle valve.
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awarded  Popular Question
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awarded  Yearling
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awarded  Student
Mar
17
comment Constant belt squeak
That is a neat trick!
Mar
17
comment Mazda 3 on acceleration drops engine power
The only way I've ever found cracked high-tension leads is by running my fingers down them searching for cracks. Unfortunately, I would find them not by feeling the crack but by being electrocuted by the leaking voltage. Fun times.