My car started making a puttering noise all throught driving and sounds like a lawn mower now for some reason. the car is lacking alot of power. Can someone help me figure this out? it literally sounds like a subaru with a fart can. NOT GOOD!! HELP :[

 

First thing I'd check is the cat to see if it's clogged.

 

Sounds like the motor isn't firing properly. Have you washed the engine bay recently? Water might've gotten into the spark plug holes, shorting out the plugs.

 

um hate to say it but when my stock gsr sounded like a suburu it was because I cracked a ringland on the #3. You could see smoke coming out the breather tube going from valve cover to intake if you removed it. Go to harbor freight and buy a $20 compression test gauge.

 

Im going to go out on a limb and give you the worst case scenario. You probably burnt an exhaust valve..... Same thing happened to my car. The transition was very obvious.


Do what I did:

Start the car at idle, pull out each spark plug one at a time from 1-4, and the car should try stall out. If there is no change in performance when you pull a spark plug wire out, and it stays the same, then that is the cylinder that is giving you grief. So it might either be:

The spark plug wire for that cylinder
The spark plug for that cylinder
The cap (in the dizzy) might be corroded for that cylinder
Bad injector for that cylinder
Bad piston rings
Bad exhaust valves

If you do a compression test, and you get SOLID results, and the compression doesnt change MUCH by adding oil and doing a wet test, then this ELIMINATES the possibility of it being the last 2.

If you stick a screwdriver inside your spark plug and bring it close to a ground and hear a spark, that eliminates the first 3

I don't know how to check injectors, I think you can just pull the spark plug out and smell it for unburnt fuel (if you have low compression that is).

Best of luck!




EDIT: Lets say you get a compression tester and these are your results:

180 180 30 180

Then you repeat the test WET and get this

190 190 30 190

This means that In cylinder 3, you either have a blown exhaust valve or a leaking headgasket, and the only way to tell would be to get a leakdown tester. You would need to put the 3rd cylinder at top-dead-center of compression stroke (Meaning that all the 4 valves are closed) and pump air in through the spark plug hole. Then while air is being pressurized inside, you just listen for any noise by your muffler. If you hear air, then your exhaust valves are burnt, if you don't hear air at the exhaust OR intake (highly doubt its intake), then you have a blown headgasket, which you could most likely see from white water vapor coming out of your exhaust.

 

You could also just check the cam timing. Also not sure what I was thinking with the cat -- just super tired i guess...

 

Ditto the above^^^

A clogged cat would result in ever decreasing power and a "shitty" sounding exhaust, not sure if I would describe it as "a subaru with a fart can".

If car starts and sounds "OK" when idling, but starts sounding like the Subaru with a fart can when RPMs go up, check the cat. 94

 

It's a cylinder or two not firing causing that sound a clogged cat would cause loos of power but not that noise and it wouldn't just happen out the blue. Check spark/compression

 

its not running on all cylinders.
before you start looking at cam timming and everything else. start easy and look at your spark plugs.... i had the electrode break off on my gsr one time and had to limp it home on 3 cylinders.

 

x2

 

My car has been doing the exact same (Subaru) thing
since mid summer .
I changed the Spark plugs and no luck
I think it might be my wires.

 

my brother had the same problem in his EP3, he changed all the spark plugs, spark plug wires and o2 sensor (o2 sensor been messed up before the subaru growl) so it might be ur spark plug wires

 

not sure how your brother changed spark plug wires on a car that doesn't have any.

 

one of the plug wires may have cam loose some how

 

Take a nice long screwdriver and put the tip up against the side of the injector. If you put your ear against the handle end you should be able to here the injector ticking.

 

Mine did that after I did my timing belt. Turned out both my cam gears were off which didn't even line up correctly behind the back plate. And it sounded like a boxer engine. Got it TDC and finally went away.

 

You guys are awsome! Will definetly try all your advice!!

 

Id say check the injectors it could be just that. Same thing happened to me last week after getting on it on a freeway entrance. I guess after transfering engine harness a few times i ended up missing a clip for one of my injectors and didnt care or notice when i threw it back in. Sounds like the same deal. I say simply make sure your injector plug ins are plugged in to the injectors. If not then id check the injectors them selves or plugs

 

what do you mean by TDC ? im still learning haha

 

coil plug or whatever u wanna call them

 

TDC = Top Dead Center

 

Unplugged injector throws a code doesn't it?

 

I checked my codes and they were all the same lol, im obd1 maybe obd2 would im not sure. im throwing codes for o2 and intake air temp, nothing else came up when my injector unplugged

 

When I had the same thing happen on my GSR, it turned out to be a valve that had blown a piece off its face. Happened while driving on the freeway cruising at around 70mph out of nowhere.

 

That is becoming more and more common as these cars get older. My b20 came like that.