rjp98outlook

I eventually got my two left pistons replaced under waranty. I brought a recording of the noise to the dealer and this made it clear exactly what I was talking about. Two days after that he called me and explained that he found an internal memo suggesting they replace the two pistons on the driver side with a special countermeasure design that has a tighter clearance. If you ask for this you will eventually get it if you want. Just be patient and document every failed attempt at the dealer. The contermeasure pistons are out there. I saw them with my own eyes and held them in my hands. Good luck. Unfortunately this had no effect on the noise in my case because it was apparently not piston slap. I sold the car after this because I could not stand an engine sounding like that. I think it was more evident because I had a manual trans. While I was at the dealer I tested a 6 cylinder outback. There is one word for this engine. SMOOTH. Such wonderful relief! No lumpy exhaust. No embarrasing knocking. Just smoth as silk. Like a "normal" engine. I love the 6. What a pleasure to drive.

Hi. I have read a few discussions on Subaru engine noise in this forum and I am hoping someone can help. I also have a noise problem in my 02 outback that I can't live with. I have only 26K miles on it and have been to the dealer 3 times already. The noise is a hollow knocking sound that is quite subtle (but is slowly turning my brain into jelly) and only occurs when the car is ***fully warmed up*** and under light load (like around 2500 to 3000 rpm with foot just barely on accelerator -- almost coasting) Sounds like something is loose and floating/knocking. Subaru already replace the timing belt tensioner and bracket, and just last week they replace two of the pistons (#2 and #4) with special pistons designed to not slap. This had no effect at all on the noise. As I suspected, it was not piston slap in the first place. What a waste of Subaru's money to replace these unnecessarily under warranty. What can I do now? Is this just how these engines are supposed to sound? Also, I have a manual trans which may exagerate the problem according to the dealer. Thanks Rich

I had Mobile 1 10w30 previously. I just tried Valvoline Syntec blend 5-30 this time. Same noise. No change at all.

I have 2 Outbacks, a 98 2.5L DOHC (130K) and an 02 2.5L SOHC (19K). Both have piston slap, but the 98 is significantly louder. The 02 has (had) 3 distinct noises that I can identify: (1) piston slap when cold, (2) timing belt tensioner clank when cold, (3) hollow knocking at 2800 RPM only when warm and under light load. I recently had the timing belt tensioner replaced on the 02 and the clanking noise it was making for the first 8 mins of operation was completely cured. I still hear the cold piston slap, but it is minor and I don't care about it. What bothers me the most is the hollow knock. It gradualy comes on as the engine warms up and never goes away. I recorded it and took it to Subaru. I took the Service Manager for a ride to demo it. He said it was normal. I think it is embarrasing. This engine only has 19K miles on it! Who, of my friends/family is ever going to buy a Subaru after taking a ride in mine I asked him? He offered to contact some district representative to have them come and evaluate it. He says only they can authorize an engine teardown. Something is definitely loose in this motor, banging metal against metal as the oil thins out it appears. I was able to get a real good recording of it by placing the mic at the top of the carpet on the passenger floor compartment while driving. Its frequency is half the engine RPM. I'm beginning to suspect that the only cure for Subaru noises may be a good stereo. It's a shame, I'd really like to enjoy the sound of my engine.

I had a similar noise on my 2002 outback. It was loudest around the top, right, front of the engine (driver's side). I recorded the noise and took it to the dealer along with a description. They listened to it and decided to keep the car to check it out. They ended up replacing the timing belt tensioner and the noise went away. It is a known issue.

Yes, it is probably due to oil thinning out when it warms up. (btw, no additive or oil change makes it go away so far). How can I investigate this further. I took it to my dealer twice (it only has 19K miles on it and is under waranty). They say this sound is normal, I say it is not and sounds embarrasing. There is clearly a hollow knock every time under the conditions I described. Something is banging against something, and I don't think it should be. They did replace the timing belt tensioner last week, but it did not have any effect on this nocking, however, it totaly fixed another noise I was having when the engine was cold! That was great service I thought. We were hoping the same defective tensioner was causing both noises, but apparently not. Anyone have any clues as to what this might be? I think I will record it and bring to the dealer. Thanks Rich

Hold on! If you are interested, I am selling my 98 Outback you may be interested. It is in EXCELLENT condition. 129K miles, white, NEW head gaskets, new clutch, water pump, radiator, leather interior, 5sp. I want 4200 for it. I am in NW new Jersey, I see you are only in PA. Email if interested. rjpjnk@earthlink.net Rich

Well, I suppose this could happen, but the first thing I changed was the radiator. Now I have a perfectly good radiator for sale! since there was nothing wrong with it. 98 Outback 2.5L BTW. Call if interested. Rich

The noise I hear also never goes away. It occurs only under very light acceleration at about 2800 RPM. It is a hollow knocking. It does not start until the car is warmed up. When did your noise happen? COuld you hear it at idle, or only at a certain RPM or load? Thanks

Hi. How did you manage to get your pistons replaced? My 02 is pretty darn noisy at only 18,000 miles. Can I have this fixed under waranty too? Thanks Rich

Yep. Definitely sounds like a head gasket. I just finished replacing my head gaskets yesterday on my 98 Outback. Today I drove it to work and NO MORE OVERHEATING! This is a difficult job, had to pull the engine. Took me 21 hours (also did clutch, timing belt, water pump, resurfaced heads, etc). If you have any questions email me and I will tell you of my experience. By the way, I am selling the car now if you are interested. It is a white Outback 5 spd, leather interior, 1998 2.5L 129K miles. I'd like to get 4000. Runs and looks perfect. Rich

I'm not sure this noise is piston slap. For one thing, it does not diminish at all when the engine heats up. It is always just the same, and only under light acceleration.

Hi: I just purchased a 2002 outback with only 17,500 miles and I am a little suprised that the engine is still noisy. There is a moderate knocking sound under light acceleration around 2500-2700 RPM only. Wide open it's fine. Idle is fine. Noise is same whether engine is cold or hot, so I don't suspect piston slap. I have only 2 days left on the 3yr/36K waranty (though I think the engine is covered under 5yr/60k) and I am wondering if I should take it to the dealer or if this is normal. My old 98 DOHC 2.5 phase 1 was noisy too, but I was hoping this was eliminated in this newer SOHC 2.5 phase 2 engine. Thanks for any info. Rich

Thanks, but it is fixed now. The problem was a bad IAC valve just like the diagnostic code suggested. I tried cleaning it well, and I also tested it electronically. Both opening and closing seemed to work perfectly. I even boiled it in a pot of water to make sure the temperature controlled mechanism closed as well. Everything looked good, but it was defective still. I found one at a junkyard and now it works perfect (good thing too, because this part lists for 328.00!). By the way, I purchased the entire intake setup including: (1998 Subaru 2.5L) Throttle body TPS sensor fuel injectors coil pack misc vacuum devices and hoses Intake manifold. All are for sale now for any reasonable offer. Rich

This morning my car was hard to start. When if finally did start, it appeared to be running fine, but 1 mile down the road it stalled. I restarted (check engine on now). Appears to be running on 1 or 2 cylinders and could just barely drive back home. Could not exceed more than about 10 MPH. Stalls with foot off gas. Only one engine code stored 1507. This problem came on suddenly. My car was running perfectly up till yesterday. I think the code indicates a problam with the idle control, but I think this is probably secondary to the problem. Something is causing some cylinders not to function. Thanks for any help Rich

From what I have heard, the potential danger in not adjusting valve clearance is not that the clearance will increase, but that it will decrease. An increase leads to noisy valves (tapping), but it won't kill you engine. A decrease, however, can be fatal. From what I understand from reading, as valve seats wear over time, the valve rises higher and higher in the head when it closes, and this means there is less and less clearance between the lifter shim and the cam lobe. This can begin to reduce the amount of time the valve spends closed in direct contact with the head. The problem is that this is the valves method of staying cool. It must conduct heat into the seat when closed. If your clearance ever gets to zero, the valve will not touch the head firmly at all and it will burn up. I hear this is particularly an issue for exhaust valves. I guess this is why they get .25 mm setting while intakes get .20. I would be happy to hear from anyone more experienced with this. Thanks. By the way, my 98 outback is running fine now with its new shims, timing belt, tensioner, and water pump. But it is still a noisy engine. Maybe I'll pull it out next year and rebuild completely (get those *()&(*&*&^ slapping pistons out!) Rich

Steve: Most of the clearances were smaller than spec, but 1 or 2 were larger. I think this engine must be in very good condition. The worst shim was off by about .002 inches (5 shim sizes). The engine has 114K miles. The worst exhaust valve had decreased from its ideal .010 to .008. I suppose it was a waste of time to do this job given how little the clearances were off, but you never know until you look, and it is recommended at 100K. I'll check again at 250K RIch

It is not a difficult job, but it requires patience and the ability to really embrace your vehicle in many interesting positions.. Yes, the dealer had all the shims I needed in stock. Basically here is what you do: (1) Remove the valve covers (and all the stuff in the way) (2) Remove the right side timing belt cover. (if you want to use this to aid in positioning of the valves according to the Haynes book. Saves a little time, but probably not worth it, yoiu can simply observe the valves directly. (3) Turn the crank pully until some valves are at the lowest point on a cam. (4) Measure the clearance between the cam bottom and lifter shim with a flat feeler gauge. (5) Repeat steps 3 and 4 untill you have measured all 16 valves. (6) The desired clearances are .20 mm intake and .25 mm exhaust. Any gap that differs by more than about .02 mm should be reshimed. Go through your list and see which ones exceed this. (7) Remove the shims on the lifters for these valves only. I did this by using a large screwdriver to piviot against a rough part of the cam and push the lifter bucket down by its edge with a twisting motion. The spring tension is not too strong this way. While holding the bucket is down, pop out the shim by pushing a very small screwdrived in the little side gap designed for this. Push it out of the way to make it fall to the ground, or grab it with needle nose pliers. This method seems to work very well. You need to use a stubby screwdriver for the intakes to work from under the cam. The exhausts are a little easier to remove. (If there is more interest in this I will post greater details). (8) Identify each shim by writing the valve number it came from on the back in marker. (9) Go inside and make coffee. Measure the thickness of each shim with a micrometer, and based on this, calculate the desired thickness of the new shim that would be required to bring the clearance to desired clearance (either .20mm or .25mm). (10) See if you can reuse any of the existing shims you are removing, and go buy the rest at the dealer (6.38 each). To make things easier, I suggest converting feeler gauge measurements to mm right away and working entirely in mm rather than inches. You need resolution better than 0.001 inches idealy, so measure carefully even to the point of saying the clearance is in between guage sizes, i.e., 0.0095, etc. Remember that a single thousandth of an inch (0.001) is 2.5 shim sizes! There are 60 shims available in increments of 0.01mm. Good luck Rich

Well, I didn't get any replies, but as an FYI, yesterday I did the job without the special compressor tool and it worked out fine. It taks a little longer, but it is definately possible. I replaced 9 of my shims. I only needed a few screwdrivers and needle nose pliers to replace valve shims with engine in vehicle. Rich

RodA2003 (or anyone): Can you please explain how you were able to change the valve shims without the "special tool" as described in this thread? I would like to do the same. Thanks Rich

Hi. I have a 98 Outback, 114K, and I am presently changing the timing belt and tensioner. I am thinking this would also be a good time to adjust the valve clearance. (Solid lifters, DOHC.) I have heard that some people have been able to accomplish this with the engine in the car and without using the special Subaru tool 498187100 to compress the spring to get the shims out. If anyone has done this, could you please explain how it can be done. Thanks very much Rich