bhelser Posted July 28, 2010 Share Posted July 28, 2010 OK, so I know I have a few problems with my 1993 Subaru Impreza Wagon, but a new one popped up yesterday.... to start, my car is loud at all times, I have been told it is could be several things, the exhaust manifold, head gasket (but not the heads), or exhaust leak. I admittedly know very little about cars...so I am just going from what I have been told. I don't have the funds to get the noise fixed, its been like that for a couple years, besides the excess noise I haven't really noticed any performance loss and the plan has always been to drive the car until it quit for good..... Well, new noise/issue popped up yesterday that I have no clue what it could even be..... When I get over 60 mph and let off of the gas there is a grinding/rattling noise. It is very loud, but doesn't seem to affect anything as far as power/performance. If I press the gas pedal it goes away, but as soon as I take my foot off the gas it is back. Once my speed gets below 60 mph the noise is gone. My first thought was the transmission, hoping that is incorrect...the transmission has about 30k miles on it, was done about 4 years ago (20k of those miles in the past 9 months - new job requires a long commute) help?!? Quote Link to comment Share on other sites More sharing options...
markjw Posted July 28, 2010 Share Posted July 28, 2010 You at least have to tell us if it's a auto or a 5 speed. Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 (edited) I guess that would help huh? :-\ 1993 Impreza Wagon Automatic 4 cylinder 1.8 liter FWD 162,000 miles Edited July 28, 2010 by bhelser Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 28, 2010 Share Posted July 28, 2010 That narrows it down quite a bit. Kinda sounds like a loose heat shield. With the car in park engine running slowly rev it up to about highway speed (2,000 - 2,500 rpm) and let it back down slowly to idle and see if you can reproduce the noise while sitting still. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted July 28, 2010 Share Posted July 28, 2010 have you ever had any axle work or cracked axle boots? or is one of the inner boots cracked right now? notice any recent burning smells? could be an axle, the inner joints particularly will vibrate/grind at certain speeds. my guess is the axle currently has a busted boot or the axle was replaced previously with an aftermarket. heat shield is good to check too. your loud issues that you've had for a few years is not anything like an intake manifold or head/head gasket issue, no way you could drive that long like that. probably just the exhaust or gasket which is no big deal, you can drive it indefinitely like that. Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 I will try revving the engine in park and see what it does. I have had the car about 4 years and the only thing I have done to it (other than oil change, air filter, etc.) is had the water pump/timing belt replaced about a month ago. will report back in a while with what I learn (or don't learn ) Quote Link to comment Share on other sites More sharing options...
SuBrat84 Posted July 28, 2010 Share Posted July 28, 2010 Well.. I was going to say carrier bearing.. but, as it's FWD and not AWD.. that rules that out. So, my next guess would be in agreement with the bad axle theory. ripped/torn boot tossed all the grease, dried up, and now it's "getting crazy" without load on it. Another possibility is a wheel bearing.. but you would probably get some pretty crazy vibration if that was the case. I do agree you should try to duplicate the noise with the car idling in Park or Neutral. I also agree that the "loud car" for a couple of years is probably a hole in the exhaust somewhere pre-muffler. Maybe a bad donut gasket.. hard to say without hearing where it is loud at.. Quote Link to comment Share on other sites More sharing options...
SuBrat84 Posted July 28, 2010 Share Posted July 28, 2010 had the water pump/timing belt replaced about a month ago. Did you have the pulleys and tensioner replaced as well? Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 Did you have the pulleys and tensioner replaced as well? no.....is that bad:confused: The water pump went out, and I knew enough to have the timing belt replaced since they were in there already....but obviously did not know enough... Quote Link to comment Share on other sites More sharing options...
SuBrat84 Posted July 28, 2010 Share Posted July 28, 2010 The pulleys and tensioner should be replaced every time the timing belts are. At LEAST every other time.. They dry out and go bad just like any other bearings.. It's possible your noise is coming from there.. but should be replicable at a stand still just revving the engine.. At 160k the pulleys and tensioner should be replaced if they never have been before. Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 OK, just started it up, and as it was starting I could hear the noise, as the engine got down to an idle it went away (as gradual as the engine slows). As I rev the engine the noise started up when I got around 2k RPM. I feel like I am playing the game clue.....but I don't have a clue:lol: does this give anyone insight? Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 28, 2010 Share Posted July 28, 2010 You need to pinpoint the location of the noise as much as possible. Get under the hood and rev the motor (either by hand using the throttle cable or with a friend in the car.) If it's coming from the timing belt cover area at the front of the engine you should have the belt/idler/tensioner looked at immediately. If it's coming from under the engine toward the rear it could be a loose heat shield on the exhaust. Might even try pushing on the shields with a wrench or large screwdriver, see if it changes the sound or if you can feel the vibration. I tend to think this is the more likely cause. Good luck. Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 best I can tell it sounds like the back of the engine area..... I will have to do so tonight at home (50 miles from work)...fingers crossed Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 28, 2010 Author Share Posted July 28, 2010 Because I can't stop thinking about this, and I know I can't get anymore info for a couple hours, I have a question..... IF it is on of the heat shields (and from the research I have done on other sites, I am leaning this way too)....why would it ONLY happen when I take my foot off the gas when cruising on the freeway? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 28, 2010 Share Posted July 28, 2010 Resonance. There can be many different frequencies that cause heat shields to rattle. The will resonate with the vibration of the engine/drivetrain depending on load, engine speed, etc. They might make the noise at other times as well but you just seem to notice it more often at highway speed maybe because you spend more time driving on the highway. What you need to find out is whether it is engine, exhaust or drivetrain related. By determining if it occurs at certain engine speeds, or only at certain wheel speeds. Heat shields are easy to check. Jack up the car (use jack stands) crawl under and tap them with a rubber mallet. If they clang around and make a bunch of racket, or you see them physically move they're loose and need to be either removed replaced or tightened up somehow. Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 28, 2010 Share Posted July 28, 2010 When you are accelerating or cruising along, your engine is creating a smooth flow of exhaust gases. Take your foot off the throttle and the flow is suddenly cut off even though the engine is still turning and the valves are still opening and closing. That creates vibrations in the air column within the exhaust pipe, which can rattle anything slightly loose--like a heat shield. I may be way off base, but that's how I picture it! Quote Link to comment Share on other sites More sharing options...
Pgh_Scoob Posted July 29, 2010 Share Posted July 29, 2010 The last two replies were dead on. Nice smooth exhaust as your cruising and as soon as you let off the gas and have the slight drop in pressure allows a bunch of vibrations to travel. Its crazy at what these heat shields can sound like. I just recently finished a battle with my car and its constant rattling. At one point I could have sworn I spun a main bearing in my engine mainly because I heard a car which had spun a main bearing a few days before and all it was, was a really high pitched "squeak" you could say. Long story short it was my heat shield heading towards my muffle. Not more than a week later I had an orchestra of rattling coming from under my car. I went on a mission to quiet my car down. When all was said and done 5 of the 6 (IIRC) heat shields had to go just along the headers. One is still sticking around and Im just waiting for the day when he has to go. Sorry for the rant, I just hate those suckers and they stressed me out before I realized it was the heat shields. Hope everything works out, Greg Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 29, 2010 Share Posted July 29, 2010 I hear that. I've tried to fix mine at least a dozen times and they still just rattle again in two weeks. I gave up and just live with it now. They have their benefits, and it looks like more of a PITA than it's worth to me to try and remove them. Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 29, 2010 Author Share Posted July 29, 2010 Thanks, that makes sense why it would do it with no acceleration. I crawled under the car best I could and tried to move the heat shields that I could see, but I could only get a little way under the car as I forgot I loaned my jack to a buddy......I guess it's time to get that back! I didn't have any leverage, but was unable to move the heat shields, but don't really know what I should be looking for as far as how much the will move. I will get it up and be able to see more tomorrow.....will just have to live with the noise for now.... and of course I am assuming this is the issue. From all the searching I have done it sounds right.... If this is the issue....and as others have said from my poor description of my other noise, I may just take it in and have a new exhaust/muffler put on and let them deal with it - although I really have no clue how much that is.... Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 29, 2010 Share Posted July 29, 2010 PLEASE DON'T crawl under the car while it's up on an auto jack! Get proper jack stands or at least some heavy blockage to hold the car up. (And put the tranny in gear or park, hand brake on and chock the wheels that are on the ground.) Now repeat after me, "Yes, Mother!" Quote Link to comment Share on other sites More sharing options...
SuBrat84 Posted July 29, 2010 Share Posted July 29, 2010 PLEASE DON'T crawl under the car while it's up on an auto jack! Get proper jack stands or at least some heavy blockage to hold the car up.(And put the tranny in gear or park, hand brake on and chock the wheels that are on the ground.) Now repeat after me, "Yes, Mother!" SERIOUSLY. I had a brat fall on me.. It was very unpleasant. I may well have laid there for a looooong time and possibly died if my friend had not been there to help. I hate to be the "worst case scenario" guy.. but it may be your catalytic converter on its way out. I had one go on an SVX and it made a nasty buzzing rattling noise. Let's just hope is a heat shield! Quote Link to comment Share on other sites More sharing options...
Pgh_Scoob Posted July 29, 2010 Share Posted July 29, 2010 Thanks, that makes sense why it would do it with no acceleration. I crawled under the car best I could and tried to move the heat shields that I could see, but I could only get a little way under the car as I forgot I loaned my jack to a buddy......I guess it's time to get that back! I didn't have any leverage, but was unable to move the heat shields, but don't really know what I should be looking for as far as how much the will move. I will get it up and be able to see more tomorrow.....will just have to live with the noise for now.... and of course I am assuming this is the issue. From all the searching I have done it sounds right.... If this is the issue....and as others have said from my poor description of my other noise, I may just take it in and have a new exhaust/muffler put on and let them deal with it - although I really have no clue how much that is.... Oh man no way. I ripped mine out, it took a little bit of effort from a cut off wheel and a pry bar. I am dealing with it now though pittsburgh heat wave is killer. I had to recharge my a/c just to deal with the heat but I would rather do that then buy a new exhaust. IMOP Greg Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted July 29, 2010 Share Posted July 29, 2010 PLEASE DON'T crawl under the car while it's up on an auto jack! Get proper jack stands or at least some heavy blockage to hold the car up.(And put the tranny in gear or park, hand brake on and chock the wheels that are on the ground.) Now repeat after me, "Yes, Mother!" "Yes, Mother!" moms are so smart!!! Quote Link to comment Share on other sites More sharing options...
bhelser Posted July 29, 2010 Author Share Posted July 29, 2010 I guess I probably should have clarified myself..... I need to jack it up so I can slide the blocks under the car, so I can slide under it It will have to be a weekend project. Thanks for all the help (and concern) so far.....I am sure I will be back after I get under the car. Quote Link to comment Share on other sites More sharing options...
Olnick Posted July 29, 2010 Share Posted July 29, 2010 .....I am sure I will be back after I get under the car. And don't you be late! Mom Quote Link to comment Share on other sites More sharing options...
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