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what is it that makes cars lose so much power as they age.

my car is from 97 and it definitely did not have the same power new.

it is definitely much slower from when it was new.

 

how can power be restored? and i dont mean modding it.. i mean just getting it back to what it was like new or close.

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what is it that makes cars lose so much power as they age.

my car is from 97 and it definitely did not have the same power new.

it is definitely much slower from when it was new.

 

how can power be restored? and i dont mean modding it.. i mean just getting it back to what it was like new or close.

 

ok, it's a 97, is that a ford or chevy? :lol:

 

miles, model, trans, recent service, and ...

what's it doing wrong??

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Why cant a 60 year old man run as fast as a 20 year old.

 

 

Wear and tear. There are many moving parts the rub eachother and wear over time. If the car is not properly maintained (frequent oil changes) those parts can wear faster. The parts here are valves and more importatntly piston rings. they are required to make compression to make the car go (suck squish boom). The next one which you cna do something about is a tuneup.

 

Then there is other things like performance tires, dragging brakes.

 

nipper

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I will assume that tuneup issues (timing, spark plugs, air cleaner, fuel delivery) are not present. If you have many miles on the engine, worn piston rings/cylinders and leaky valves will cause lower compression, with loss of power. a compression test will help pinpoint this. If you have blue smoke out the pipe from oil burning, your engine is just worn out.

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To be a little more specific-

 

crud buildup in the intake/exhaust passages and on the valves blocks intake/exhaust flow

 

valves open later, close sooner, and don't open as far as valvetrain components wear

 

valve timing is retarded as the timing belt stretches (Probably only a very small amount)

 

cylinder compression goes down as the cylinder and rings wear

 

the fuel injector spray becomes less fine and even as crud builds up on the internal injector parts, and as the injector bits wear against each other.

 

The muffler could be plugging up (not a frequent occurrence)

 

The oxygen sensors could be a little out of spec, giving not quite the right mixture.

 

The mass-airflow sensor could be a bit off, not sure if that is common on subes.

 

The throttle-position sensor could be out-of-spec.

 

the catalytic converter(s) could be somewhat blocked.

 

If any of those last 4 go far enough out-of-spec it'll throw a code.

 

 

Dave

Edited by CNY_Dave
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ok, it's a 97, is that a ford or chevy? :lol:

 

miles, model, trans, recent service, and ...

what's it doing wrong??

 

sorrry. its a 97 legacy L. automatic and just hit 157k

 

its not doing anything wrong. its just old and slow.. but i dont know what it is about being old that makes care lose so much power. i just heard of leaking past pistons but i dont really know much else.

 

miles

airfilter - 10 k

fuel filter - 3k

spark plugs/wires- 10k

oil - 800 miles

 

its definitely running smoother than when i got it first.. but im just wondering about the loss of power over the years.

 

and

thanks for the all the answers

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oh yeah. the CEL does come on occasionally for the throttle pos sensor.

and by occasionally i mean twice in the last year.

 

it goes away by itself so far. its really strange.. it will be there and then maybe after 12 hours or so or just the next time i start my car its gone.

 

i unplugged it blew out any dust... i was thinking maybe it just had a bad connection or something. im not sure what the code is about... its never consistently there.

 

what should i do about that?

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sorrry. its a 97 legacy L. automatic and just hit 157k

 

its not doing anything wrong. its just old and slow.. but i dont know what it is about being old that makes care lose so much power. i just heard of leaking past pistons but i dont really know much else.

 

miles

airfilter - 10 k

fuel filter - 3k

spark plugs/wires- 10k

oil - 800 miles

 

its definitely running smoother than when i got it first.. but im just wondering about the loss of power over the years.

 

and

thanks for the all the answers

 

An occasional can of Techron injector cleaner will perk it up.

 

I like the list posted above, and I'd put bad injector spray at the top. When that happens, and it does, excess carbon accumulates and causes wear and stuff.

 

New plug wires I recommend, because those seriously degrade at that mileage. There are many opinions about plug wires, but high quality silicone aftermarket ones are avialable, IMO. Blue NGK.

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  • 2 weeks later...
what is the difference in all the different spark plug wires... as long as they consistently conduct the spark, isnt that good enough? what more could they do...

 

Some wires are better quality than others and the better ones let the spark plugs work better. Through trial and error, most here feel that OEM parts are the best way to go and give the least trouble. NGK rules.

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what is the difference in all the different spark plug wires... as long as they consistently conduct the spark, isnt that good enough? what more could they do...

 

 

There is much more to a spark plug wire then conducting spark. They have to contain 100,000 volts or more. They must be shielded from induced voltages from other wires (not a big issue on a sooby). They must deal with engine oil and under hood temps of 300 degrees or higher. They also must assist in keeping ingnition noise from showing up over the radio.

 

Wires are made of silicon insulation. Poor quality silicon (read cheap wires) will quickly break down under the stress of high voltage and engine temps and allow for voltage leakage.

 

Wire trees are used to keep wires from inducing spark in its neighboor wires.

 

http://www.generalcable.com/NR/rdonlyres/F3629AA7-1B9E-40E6-A74B-4D3949CD1B9B/0/AUT_0060_1002.pdf

 

Skip the part where they are saying thier product is the best but thier points are valid in wire construction.

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Have you changed the transmission fluid recently? If it's the original, it might help a little.

 

Z

 

yup

i did it.. and then i had to get an mpt clutch changed?

which was done at the dealership so im assuming the fluid was drained and refilled then too...

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so when i first got the car... it did 3500 miles fine...

 

and then for about 900 miles, it leaked and i mean leaked a quart of oil every 300 miles.. but somehow that some how fixed itself.. i dont know how... or why.. but thers no smoke from dripping on the exhaust anymore

 

 

 

and ive just been reading about seafoam and how it can take out carbon buildup and cause high mileage engines to lose compression.. and perhaps clean out any thing that was clogging up potential oil leaks.

 

does techron have a similar effect? do you think that is what caused my car to start pouring a quart of oil every 300 miles...?

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An occasional can of Techron injector cleaner will perk it up.

 

I'd suggest the Techron Concentrate rather than their injector cleaner. I'm not a big fan of additives but I do believe in that stuff. A bottle in the gas tank every 6 months really makes the old '95 EJ22 smile.

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does techron have a similar effect? do you think that is what caused my car to start pouring a quart of oil every 300 miles...?

 

Nope, Techron won't have any effect on your oil.

 

You might want to replace your PCV valve and clean the hose leading to it, that may help.

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Nope, Techron won't have any effect on your oil.

 

You might want to replace your PCV valve and clean the hose leading to it, that may help.

 

hm its about 10k miles old.. and how would that help? isnt that just about recirculating air or something.. i dont realyl know what it does.

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hm its about 10k miles old.. and how would that help? isnt that just about recirculating air or something.. i dont realyl know what it does.

 

Yeah, it recirculates air--and all the crap in it from the crankcase. Try pull the PCV and the hose and flush them out with an aerosol spray, I think you'll be happy you did!

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There is much more to a spark plug wire then conducting spark. They have to contain 100,000 volts or more. They must be shielded from induced voltages from other wires (not a big issue on a sooby). They must deal with engine oil and under hood temps of 300 degrees or higher. They also must assist in keeping ingnition noise from showing up over the radio.

 

Wires are made of silicon insulation. Poor quality silicon (read cheap wires) will quickly break down under the stress of high voltage and engine temps and allow for voltage leakage.

 

 

 

Good summary. Additionally they have to conduct those 100,000 volt pulses, with absolutely no *lag* or delay. THOUSANDS OF TIMES PER MINUTE!

 

 

 

I'd say that the most common thing I do to restore power to an engine is to clean the carbon off of vavles, and piston crowns. (assuming rings and all else are still decent)

 

I do this every single time I have an engine apart for head gaskets. I set the piston slightly below the deck, and use a wire wheel on the end of a drill to clean it's head. Fine, soft bristle, won't scratch the iron cylinder walls, but will ussually get all the carbon. Sometimes I have to take a screwdriver to crevices in valve notches and such. WD-40 aids the process.

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