Good Day Everyone, I recently joined this site, I have visited before and had a lot of help when working on my subaru. I own a subaru impreza TS 1.6l non turbo, automatic. Its not that fast! but it is used as a family car and it does the job. Recently however I noticed the engine was losing power - slow uphill and acceleration. So i decided a tune-up was in order.

 

I changed the oil, oil filter, spark plugs, transmission fluid, air filter. This did NOT improve or solve the performance issue. After a while the check engine light came on. I normally work on the car myself but I do not own a diagnostic scanner so I took the car to a mechanic. The mechanic told me the O2 sensor was faulty so I had it replaced. The check engine light came off but came back on after 2 days.

 

Replacing the O2 sensor did not solve the problem, the car still struggles to get up hills and accelerates very very slowly. A few weeks after I took the car to another mechanic, he scanned the car and told me to replace the spark plugs and wires. I did, and the problem still was not solved.

 

Tired of the problem, I took steps to fix the problem myself, I cleaned the throttle body, had the injectors cleaned and replaced the fuel filter, the problem still was not resolved. 

 

 

So in a nut shell - Car engine - lazy

 

Replaced-

engine oil

oil filter

spark plugs

spark plug wires

o2 sensor

air filter

fuel filter

transmission fluid

cleaned throttle body

 

 

So now i'm here, asking- please can someone help!!??

 

 

So engines needs 3 things to function. Fuel spark and compression, since you cleaned the intake system and cleaned the fuel system, I'd check the spark first, pull a plug and crank the car with the plug out to see if it's getting good spark, if so you're clear on one of the 3 necessity of an engine. Next I'd check your fuel, you said you cleaned the intake, so maybe hook your fuel line up to a psi gauge after the fuel filter and make sure you're getting an adequate gas supply, next comes the dreaded compression if all those other category's check out good. Time to do a compression test next on your engine and see where the head gasket is at for remaining life. After that I'm no good on newer subies. But it gives the garage monkey mechanics a place to start to try and see where the problem could lie.

Has your timing belt been changed at the correct 104,000 mile intervals? If not, do it now.

Good Day Everyone, I recently joined this site, I have visited before and had a lot of help when working on my subaru. I own a subaru impreza TS 1.6l non turbo, automatic. Its not that fast! but it is used as a family car and it does the job. Recently however I noticed the engine was losing power - slow uphill and acceleration. So i decided a tune-up was in order.

 

I changed the oil, oil filter, spark plugs, transmission fluid, air filter. This did NOT improve or solve the performance issue. After a while the check engine light came on. I normally work on the car myself but I do not own a diagnostic scanner so I took the car to a mechanic. The mechanic told me the O2 sensor was faulty so I had it replaced. The check engine light came off but came back on after 2 days.

 

Replacing the O2 sensor did not solve the problem, the car still struggles to get up hills and accelerates very very slowly. A few weeks after I took the car to another mechanic, he scanned the car and told me to replace the spark plugs and wires. I did, and the problem still was not solved.

 

Tired of the problem, I took steps to fix the problem myself, I cleaned the throttle body, had the injectors cleaned and replaced the fuel filter, the problem still was not resolved. 

 

 

So in a nut shell - Car engine - lazy

 

Replaced-

engine oil

oil filter

spark plugs

spark plug wires

o2 sensor

air filter

fuel filter

transmission fluid

cleaned throttle body

 

 

So now i'm here, asking- please can someone help!!??

many possible causes including but not limited to; clogged exhaust (usually cat conv.), slipped timing belt, bad knock sensor, vacuum leak

 

more details on the car and post the codes - Pep Boys or similar will usually scan for free.

1.6L NA? Yeah, that engine isn't exactly a power house to begin with. Did you buy the car and it was weak? Or did it gradually loose power over time? 

 

I'd look at a clogged cat too. Which O2 sensor did you replace? Upstream or downstream? Easiest way to check for a clogged cat is to attach a vacuum gauge to a vacuum line "T" it into an existing line on the throttle body (stay away from a fuel pressure regulator though). Let the engine warm up completely and get to normal operating temps. Letting the engine idle in Park/Neutral, where's the vacuum needle at? Is it bouncing? Holding steady? What numbers per sq. inch is reading? Come back with those figures and we can tell you if the cat is bad. You can use a vacuum gauge from a parts store, or get someone to loan you a boost/vacuum gauge from a turbo car as it'll tell you the same thing.

Edited October 29, 201411 yr by Bushwick