what causes a high-mileage car engine to lose power?

CrackRabbit

Lifer
Mar 30, 2001
16,642
62
91
Possibly.
With no other description of the car or problem it could be anything from a bad air filter to little green men stealing your sparkplugs.
 

jlbenedict

Banned
Jul 10, 2005
3,724
0
0
worn parts.. particularly... pistons, piston rings, and the chambers...
when those are wore... you lose compression, thus loss of power..
 

imported_itr

Senior member
Mar 2, 2005
900
0
0
Originally posted by: jlbenedict
worn parts.. particularly... pistons, piston rings, and the chambers...
when those are wore... you lose compression, thus loss of power..

so if you replaced those parts, the engine would perform like a new engine?
 

tfinch2

Lifer
Feb 3, 2004
22,114
1
0
Originally posted by: itr
Originally posted by: jlbenedict
worn parts.. particularly... pistons, piston rings, and the chambers...
when those are wore... you lose compression, thus loss of power..

so if you replaced those parts, the engine would perform like a new engine?

If you do not know what replacing those parts will do for an engine, you should not replace them.
 

Analog

Lifer
Jan 7, 2002
12,755
3
0
compression loss = power loss. Can't get around that one, even with additives that say 'miracle' somewhere in the title. :)
 

skyking

Lifer
Nov 21, 2001
22,820
5,983
146
it is a systemic thing. The FI system is not what it was, the ignition, tranny, rings, valves.
add em up and it = something less.
You may have a broken or messed up <insert part/system here> that would bring most of it back.
 

thedarkwolf

Diamond Member
Oct 13, 1999
9,036
129
106
Originally posted by: itr
nothing wrong with the car. it just has over 200 grand miles.

What makes you think there is nothing wrong with it? If you have all of a sudden noticed a drop off in power there is something wrong with it. The compression ratio is going to be a extremely slow drop off over the life of the engine and you aren't going to notice a power drop off unless something major goes wrong.

If the car uses a timing chain and it has never been replaced in 200k miles it will be pretty stretched. Like the cylinders it would be a gradual thing but if the chain has stretched enough it could jump a tooth and that would cause a very noticable change in power. Then there are just all the normal tune up parts.