Practical questions related to engine power – or the loss there off. Questions about electrical power and powered accessories should use [tag:electrical].

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6
votes
1answer
854 views

Measuring Horse Power and torque without a dynamometer

I know I can take my car to a workshop and have a Dyno Run and can read the HP and torque figures from that. What I want to know, is there an alternative way to know the HP and Torque figures without ...
8
votes
3answers
5k views

Does accelerating faster worsen fuel efficiency?

I've often heard that accelerating harder makes for bad fuel efficiency, but have yet to be given a sound explanation of why. Naturally this makes me question this advice. Now obviously when you ...
5
votes
2answers
59 views

Rough idle + slow acceleration + engine dying after spark plug change

I recently changed the spark plugs and wires on my 2002 Ford Focus SE with Zetec (DOHC) engine. I used NGK TR5IX (7397-4PK) Iridium IX plugs and Motorcraft wires. When I received the plugs, they were ...
9
votes
2answers
67 views

No power but battery, alternator, and connection are good

This involves a company truck, 08 Chevy Silverado. I am not a mechanic or DIY nor do I play one on TV. The problem I am having is that every 2 or 3 months this truck will not start and completely ...
5
votes
2answers
170 views

Engine weakening for Bajaj pulsar 220F

Everyone knows that apparently a bike looses it's power with age. But I refuse to agree to this. Shouldn't proper care allow your bike to maintain its pickup over the years? I own a 2014 Pulsar 220 ;...
10
votes
6answers
98k views

The battery is fine but my car will not start not even a clicking sound

When I turn the key in to start all the lights on the dashboard go out completely and when I turn it back to the off position the dash lights back up. What could the problem be if the battery is okay?
5
votes
3answers
81 views

Motorcycle randomly loses power

I have a single cylinder, 200cc, carbureted, 5 speed, 12V, 2006 Lifan LF 200 motorcycle that typically runs fine. It will sometimes randomly lose power and I cannot get it to go above 25 mph. When ...
7
votes
3answers
382 views

Loss of engine power when using headlights

i have a nissan march 2003 (K12). when i turn on the headlights, it loose its engine power. alternator and battery are ok. anybody knows what would be the cause? thank you in advance. additional ...
1
vote
1answer
59 views

Designing IC engine [closed]

I am trying to design a theoretical internal combustion (IC) engine. The ultimate goal is to achieve 3000 hp with this engine, for which I know I will need low bore x stroke ratio, high compression, ...
0
votes
0answers
26 views

Engine non-start after oil light came on

I was driving a Mark IV Volkswagen Golf on the highway. As I was overtaking, the engine oil light showed on the dashboard, so I stopped. I checked the oil, which measured okay. I tried to start the ...
1
vote
0answers
31 views

2003 Mercury Sable - lack of power and hesitation when accelerating

2003 Mercury Sable When accelerating from stop sign, red light, attempting to get on the highway the car has no power when applying pressure to the gas pedal. Struggling to get past 20-25 mph. Once ...
15
votes
5answers
77k views

What does the 'cc' mean on a motorcycle?

I'm relatively new to motorcycles, my flat mate taught me how to drive his two Royal Enfields around New Delhi, and for the past year and a half I've been taking care of them as they break down ;) ...
2
votes
3answers
117 views

Which motorcycle engine and transmission configuration would have a higher top speed? [closed]

Can a higher cc (displacement) bike with 5 speed transmission or a lower cc (displacement) bike with 6 speed transmission have higher top speed? Example: Yamaha R15 (150cc, 6-speed transmission) v/s ...
0
votes
1answer
38 views

very low speed in fact no pick up at all and lot of vibration of my ford fiesta diesel

I don't know how to maintain a Ford Fiesta diesel car's engine which has lot of noise with no pick up and power steering oil leakage. My car has lot of problems like pick up, speed, mileage, rattling ...
4
votes
1answer
60 views

Re-wiring Harness in Jet Boat w/ Ford 460

I'm replacing the wiring harness on my jet boat. It has a Ford 460 in it. The boat has five gauges on it. A tachometer, oil pressure, amperage, fuel gauge, and water temp. There is also a toggle ...
4
votes
2answers
8k views

how fast does the alternator charge the battery?

It would appear that the common word of wisdom is that car alternators provide 50A of output. I actually looked at the supposed specs for my 2008 Jetta 2.5L on the internet -- a compact car -- and it ...
4
votes
1answer
286 views

97 Jeep Cherokee check gauges light came on and then my battery gauge dropped down to 9 didn't lose any power?

I'm so confused I had just left my house and got 3 blocks away and my check gauges light came on, then my battery gauge dropped down to 9v. My Jeep didn't lose power, and the radio, heat, lights and ...
6
votes
1answer
93 views

Where can I find a power adapter to run a car stereo from a wall outlet?

I have a car stereo head unit that I'd like to repurpose as a radio for my garage. Given that, I'm looking for some kind of power adapter / transformer that I can plug into a wall outlet and splice ...
20
votes
6answers
1k views

Will higher octane fuel improve towing power?

According to Will higher octane fuel improve gas mileage? higher octane fuel does NOT notably improve fuel efficiency. Will higher octane fuel, increase power while towing? I looked online and ...
2
votes
0answers
22 views

2011 toyota tundras loses power under load

My 2011 Toyota tundra loses power while under load it doesn't completely shut off but does not respond when pressing gas pedel. This is an occasional thing not constant
2
votes
0answers
34 views

On my '99 Grand Am the electric windows, A/C, dash gauges, speedometer stop working sometimes

Sometimes they come back on in a few minutes but sometimes it's hours or maybe a day and they will all start working again at same time. Other things like radio, CD player, cruise, horn, wipers, door ...
7
votes
1answer
202 views

Rattling sound and loss of power

My brother's '85 Toyota Camry with ~190k miles started making a funny rattling sound and lost about a quarter of its power. The rattling seems to come into play when it's under load, like when he's ...
2
votes
1answer
2k views

1999 jeep grand cherokee power loss (electric)

ok guys hopefully someone can help me with this one. i have 199 jeep grand cherokee laradeo all wheel drive 4.7 power locks windows ect. in the last few weeks i have an complete power loss.. ...
4
votes
1answer
68 views

Power Steering Pump Leak…Wrong Fluid Used

I recently had to have the engine replaced in my '05 Toyota 4Runner. I got it back about 4 weeks ago and about a week ago I discovered a leak at my Power steering pump. When the engine is running the ...
12
votes
4answers
33k views

Engine power specification at different rpm?

Car companies advertise power of an engine at different rpms. Car 1: 80 PS at 6000 rpm Car 2: 85 PS at 6500 rpm What does the power at different rpm mean? Does it mean Car 1 has better power than ...
6
votes
1answer
613 views

Citroen C4 - Poor idle and low rev performance?

I have a Citroen C4 1.4 with 1360cc 16V KFU / ET3J4 petrol engine with 120.000 km. This problem appeared 3 - 4 years ago at around 40.000 km. When the engine is cold / hot there is a flat spot ...
6
votes
1answer
207 views

how do i know if my lead-acid battery has been resurrected?

The OEM battery in my 2008 Jetta SE 2.5L has been nearly fully discharged one month back (had insufficient surface charge after a prolonged use without the engine running, but leaving it idle for 20 ...
6
votes
3answers
254 views

lack of acceleration mazda 3 sport

I have a mazda 3 sport diesel on a 07 plate it has 133000 on clock, I bought this car a couple of months ago and have noticed a lack of power in the lower gears. it struggles to overtake unless I have ...
1
vote
0answers
46 views

Power door lock failure when engine is off

I have a 2003 Honda Civic ex sedan and recently the power door lock stopped working. I can manually lock and unlock all the doors and when I turn my engine on and start driving I can use the power ...
4
votes
1answer
229 views

Battery high voltage

I measured my "cigar socket / outlet" with a multimeter. Instead of 12v it had 19v. Is this normal? Is it my voltage regulator, alternator, battery that has problems? Car: Peugeot 307, 2.0 XSI 2003 ...
4
votes
1answer
50 views

ENG PWR REDUCED 2009 Chevy Cobalt LS

I have a 2009 Chevy Cobalt bought used a year ago from a dealership near me. It has about 81,000 miles on it and just recently started messing up. My coolant temp will start heating up to about 200F-...
5
votes
1answer
145 views

Honda Shadow VT750 louder exhaust noise, low power

Recently, my motorcycle got smashed by my girlfriend (who was driving behind me) in the rear. As a result of the impact, I got propelled into the rear of the car in front of me. Both fenders are ...
3
votes
0answers
53 views

“Missing” motor

My Subaru Forester 2003 runs fine until I go up steep inclines when it starts to loose power and goes into "limp mode" (ie shut down). I can restart it okay but the same thing happens after a while ...
15
votes
6answers
706 views

What is the difference between torque and horsepower?

A very basic question - what is the difference between torque and horsepower? Its all over Google, but I am really confused and can't get any satisfactory answers. I'll tell you my confusion: Torque ...
2
votes
0answers
67 views

2009 Honda VTR250 motocycle losing power [closed]

My 2009 Honda VTR250 is loosing power during long rides. The throttle at this time does not pick and it slowly stalls. I tried replacing the plugs but still has not worked. It only solves the problem ...
2
votes
0answers
131 views

Renault kangoo 1.4 2006 has no power

My vehicle has no power.. she will drive and reach normal driving speeds for both town driving or open road..however when i need to gear down to overtake or when i need power, she falters and starts ...
9
votes
1answer
374 views

How does intake manifold runner length effect the power curve of a car?

Recently I learned that a number of things such as the cam profile, compression ratio and the intake manifold runner length and volume can all effect the power curve of the engine. Here is an ...
4
votes
2answers
632 views

Can I use any portable powerbank to jump start a car

Say I have some ordinary portable powerbanks I use for my smartphone, I wonder if all of them are able to jump start a car with flat battery as long as I have a correct connector (e.g. clamp). Or ...
7
votes
2answers
125 views

How can head port volume affect the power curve of an engine?

Recently I learned that even more things other than the ones already mentioned here can effect the power curve that is produced by the engine. Here is an example of one. I understand that there are ...
2
votes
0answers
29 views

What actually is brake horsepower (BHP)? [duplicate]

I know that BHP is the measure of power of an engine. I realised that I have no idea how the number (for example 540 BHP) relates to the engine itself. Does 1 HP mean one rotation of the crankshaft ...
24
votes
6answers
2k views

When is a cold air intake system beneficial?

Cold air intake must be one of the popular mods there is, and one subject to the most controversy as well. Manufacturers of such systems advertise 5-20 HP gains, yet there are claims that this mod ...
6
votes
2answers
106 views

Car battery appears good but car won't start

My 2005 Nissan won't start today. Battery is relatively new(about one year old) and I can turn the lights on, front headlights, and it appears fine. However, when I tried to start the car by turning ...
5
votes
3answers
1k views

Larger cylinder volume, but less power, how?

KTM Duke 200 which has an engine of 200 cc, and, on the other hand, Royal Enfield Bullet 350 with a 345 cc engine. I.e. Enfield has 150 cc more than the Duke. But KTM produces 25 BHP of power, whereas ...
7
votes
1answer
216 views

What should one do to reduce the HP lost at the wheels on an automatic transmission?

I have a 1990 Toyota Supra Turbo 4 speed auto. I've done some research about automatic transmissions and manual transmissions and what are the positives and negatives of each. (For example, MT is said ...
3
votes
1answer
262 views

A Suzuki GZ125 marauder that won't power on at all

I've been having a problem with my bike. I went to go to work in the morning and it turned on ok. Left to run for a few minutes then cut out. It turned over again and same thing ... I tried a third ...
7
votes
6answers
66k views

How many amps should my car pull while it is turned off?

I've recently started having a bit of trouble with my car. I typically drive my car to and from work each day. A couple weeks ago I went on vacation and when I returned, my car battery was as dead ...
3
votes
4answers
278 views

Why dual motor Tesla has more autonomy?

Maybe the question is more appropriate for Electronics Stack Exchange, I don't know. In the page http://www.teslamotors.com/models if we scroll down we see the several flavors Tesla sells its Model S....
5
votes
2answers
7k views

Problems with Power Door Locks

I have a 2009 Honda Accord with approximately 95k miles. About 2 years ago, I began having periodic trouble with the rear driver's side door lock. All other doors would lock/unlock with the power ...
2
votes
1answer
46 views

Toyota Camry 2003 drive seat won't move forward

We have a 2003 Toyota Camry. Its driver seat power track won't move forward as it turns to the right after about 1/4 inch movement and cannot go forward. However, it does go backwards all the way. ...
0
votes
0answers
23 views

Can I increase the power in the high tension leads? [closed]

I want to increase the spark from 2kv to 7kv the spark going in one lead is 2kv and the lead coming out is at 7kv. This is for petrol engine.