Troubling Engine Noise

Interesting thread.
I'm trying to keep my 03 Vivid Yellow P5 alive as long as I can.
Number 4 cylinder has low compression so I'm only managing 18-19 MPG in mixed driving.
Anyway, I believe you said your car is a manual.
I listened to the sound bite as best I could on my PC speakers at work. It sounds more like a grinding noise than a knock.
The first easy thing to do is start the car and push in the clutch to see if the sound goes away.
After that, I would pop off the belt and see if the sound stops. It could be the power steering pump, alternator or A/C compressor. I can't remember if we have belt tensioners or not...been awhile since I had a look under the hood.
Heck, could be a loose clamp rattling against something.
 
So try this.. get a wooden baseball bat and go start your car. Lol dont beat up the car. Put the bat against things like bell housing, ps pump, ac compressor, alt, and so on. With the bat against one of those put your ear against the other end of the bat. You will hear a bearing going bad in one of the accessories or in the bellhousing. Use it like a long stethoscope but be careful of belts and pulleys. Your open ear will help you identify the sound with the sounds from the bat. Easier than removing things and you can check multiple things pretty quick.
 
I hate to leave these responses unanswered. After all, this is exactly the kind of feedback I was hoping to receive. So thank you everyone. I'm just burnt out from being stressed about it.

Nonetheless, the Protege5 is still driving. It's been about 400 miles. The sounds have not gotten better. But, I don't have a reason to believe the car is going to suddenly quit on me without warning. I really don't believe the sounds could be anything other than an internal issue, but I am not completely sure that it is a bearing. I figure it would have already gone out by now if so.

To be fair, my driving style has become more mild. I don't rev the engine past 3k, which certainly dulls the driving experience and my enjoyment with the car.

I need to change the oil and send a sample for analysis. That should be a good way to tell what's going on. Also going to take a long hard look in the oil filter.

I've been thinking long and hard about my plan for this car if the engine does go. JDM engines are all well over $1k, and there aren't a ton of junkyard engines that I would want to risk, knowing that these engines are somewhat flawed and fragile if not taken care of. I don't think I've seen a good condition running engine for under $800 so far. I don't have the expertise to rebuild the engine myself, even if it could be most cost effective. I'm sort of left wondering if this car is worth saving if the engine goes. While I really enjoy it, I'm honestly just wishing I had bought a Honda Civic right now.
 
I've been thinking long and hard about my plan for this car if the engine does go. JDM engines are all well over $1k, and there aren't a ton of junkyard engines that I would want to risk, knowing that these engines are somewhat flawed and fragile if not taken care of. I don't think I've seen a good condition running engine for under $800 so far. I don't have the expertise to rebuild the engine myself, even if it could be most cost effective. I'm sort of left wondering if this car is worth saving if the engine goes.
I'm in the same boat...er, car.
03 P5 with leather and a rebuilt transmission from about three years ago.
Car now has 250,000 miles on it. Single stage Vivid Yellow is faded.
Number four cylinder has horrible compression.
Gas mileage is down to 18mpg.
They're starting to hit the junkyards now. Found a blue one Monday and grabbed the oil dipstick.
Found a sedan a couple rows later that had leather interior. Tried to get the driver's seat but one of the bolts was stripped. My back was killing me so I left it until maybe this weekend.
I love my P5. Bought her brand new. Gonna be tough saying goodbye.
 
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I'm in the same boat...er, car.
03 P5 with leather and a rebuilt transmission from about three years ago.
Car now has 250,000 miles on it. Single stage Vivid Yellow is faded.
Number four cylinder has horrible compression.
Gas mileage is down to 18mpg.
They're starting to hit the junkyards now. Found a blue one Monday and grabbed the oil dipstick.
Found a sedan a couple rows later that had leather interior. Tried to get the driver's seat but one of the bolts was stripped. My back was killing me so I left it until maybe this weekend.
I live my P5. Bought her brand new. Gonna be tough saying goodbye.
I feel ya, but I also feel like at 250k, your P5 has seen a good life. Being the original owner does make it a little tough though I'm sure. Hope you can keep it on the road, even if that inevitably means a new engine.

Mine only has 170k and while the paint is fine at best, it's also completely rust free and has no accidents and a clean title. It just seems like the car has life left to live, except for darn the engine. Thus my frustration.
 
I am continually confused by this engine. I'm really not sure what's wrong at this point.

Changed the oil today. Only 2k miles on it, but oil is cheap and if seemed appropriate. Took a sample that's getting sent to Blackstone on Monday. I will be interested to see the results.
Also added some Lucas oil stabilizer stuff this time, so we'll see what that does.

I'm still trying to figure out if what I was seeing on the dipstick was metal bits or something else. The filter looked clean inside but I didn't cut it open. Don't really know how to do that safely.

I tried a method of testing for bad rod bearings. If you take the spark plugs out, rest something like a socket extension on top of the piston, turn the engine by hand to just past TDC, the piston starts being pulled down by the crank. If in that position, you press down on the piston with your extension and it moves or clicks, that would indicate that there is play in the bearing. No movement in my case. Of course, there are other bearings that could go bad and cause noise too.

I got under the car and listened, and the noise I'm hearing at idle is much less audible from below than from above. It's most audible from the timing belt side. But the irregularity and low pitch makes it sound like it couldn't be a timing belt or accessory noise.

I guess I'll see what comes back on the lab results.
 
Benji,
I just listened to your sound file with headphones on.
It kind of sounds like something hitting a cover. Maybe the timing chain/belt tensioner is worn causing rubbing against the cover.
Our Guzzis make a similar noise when the tensioner wears out.
My P5 motor is about the only one I have that I don't know anything about.
Once I found out that there was really no way to get considerable power I lost interest and use it as a daily driver, lol.
 
I got the oil analysis report back from Blackstone today. Here it is.

p5_oil_analysis.jpg


I'm somewhat relieved, but still kind of confused.

This seems to indicate that there isn't major internal engine damage, so I don't need to be too concerned about doing more damage by driving it. But I'm still wondering what the sound actually is. It's definitely still there, but at this point it must be either timing related, accessory related, or something in the head.

I'm probably going to pull the valve cover off (since I already have a gasket and need to replace it anyways) to try and check the valve clearances and make sure everything looks good. The car has not had valves adjusted ever I believe.
 
So try this.. get a wooden baseball bat and go start your car. Lol dont beat up the car. Put the bat against things like bell housing, ps pump, ac compressor, alt, and so on. With the bat against one of those put your ear against the other end of the bat. You will hear a bearing going bad in one of the accessories or in the bellhousing. Use it like a long stethoscope but be careful of belts and pulleys. Your open ear will help you identify the sound with the sounds from the bat. Easier than removing things and you can check multiple things pretty quick.
I wonder if anybody has tried one of the $5 - $7 stethoscopes sold on eBay or Amazon?
 
I wonder if anybody has tried one of the $5 - $7 stethoscopes sold on eBay or Amazon?

Yes!!
I have!!
Super cheap and easy!!

Screenshot_20220308-205101_Amazon Shopping.jpg



You can also use a long screwdriver and press it between your ear and different parts of your car,

but you don't want to stick the screwdriver into a moving engine part while your head is turned sideways plugging the end of the screwdriver into your ear. lol

I've been there, I've done that.
lol
 
The baseball bat keeps your head further away from moving parts lol. I had an issue once with a honda where the timing cover either got hot or something and somehow warped itself and ended up rubbing on the timing belt ever so slightly making a strange sound. It took a while to get it tracked down but once that cover came off plain as day the 3" long mark and outer edge of the belt was chaffed up. Maybe have a look under yours? Or try the bat against the cover trick to hear any weird sounds?
 
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by god mine seems to make the same noise if I am correct on what sound I am picking out of that audio. it's the heat shield on the exhaust. I pressed a screwdriver to mine and it stopped. BRB gonna get a quick vid and see if that's the same noise you are asking about.
 
March 16, 2022

Let me know what you think. It's not the most composed of videos as I need both hands to do the test, in the shirt pocket video isn't the best 😂 but I definitely hear the same sound in mine and I can make it stop by pressing that extension onto the shield. I picked that sound off as it is close to the same sound that a 00's camry 4cyl makes when the timing belt isn't tensioned right so it worried me for a sec.
 
March 16, 2022

Let me know what you think. It's not the most composed of videos as I need both hands to do the test, in the shirt pocket video isn't the best 😂 but I definitely hear the same sound in mine and I can make it stop by pressing that extension onto the shield. I picked that sound off as it is close to the same sound that a 00's camry 4cyl makes when the timing belt isn't tensioned right so it worried me for a sec.
Okay I finally got around to listening to your audio clip...and gosh that rattle does sound exactly like mine when you rev it a bit and hold it at that particular RPM. Do you think that's the heatshield rattling?

That rattle is what primarily came through on my audio clip, but it's actually not what I'm most concerned about. It's very tinny and up top, so I kind of figured it was a benign rattle and at worst, it sounds like it's in the head and not the bottom end. Also...VICS? Was your engine cold when took the video? Mine doesn't really make that noise when it's warm I don't think.

The noise I'm hearing that concerns me is a lower pitched, lower frequency clacking kind of sound. You can specifically hear it at around 0:44 in the clip, and it's hard to pick up if you focus on the rattle, but it sounds like an uneven clacking of the cylinders. Like the firing is uneven, and half of the cylinders make a slightly different noise.

The sound is only audible at idle really but it seems like the car is running more and more rough at idle, and I'm especially noticing more vibrations. It's just so weird because it runs great while driving and doesn't make any noises that sound like a knock when revving or decelerating. Also just drove 3 hours and 200 miles and the car did great.

I spent some time a while back on youtube watching videos of Mazda engines and listening to stuff about solid lifter noises. I didn't think it could be valve noise because I'm used to ticky Honda engines and this doesn't sound like a tick but more like a clack. But it sounds like solid lifters can also be a bit clacky on Mazdas.

But anyways, I think the moral of the story here is that I need to take a better recording...I will try to get my Blue Yeti out to do a nice studio quality recording of the good ol FS-DE 🤓. Also going to take the valve cover off this week to inspect.
 
I pulled the valve cover to check valve clearance and the condition of the timing belt. I've never checked valve clearances or done a timing belt so this was a bit new to me. All valves seemed within spec (0.225-0.295mm cold) except for the #2 marked cap on the top left which would only fit a 0.179mm gauge at most with cyl #1 at TDC of compression stroke. This doesn't seem too concerning to me, though I would have expected it to have more slop rather than less.

There is a chance that my method for reaching TDC was not super accurate. I couldn't see the mark on the harmonic balancer easily so I just stuck a rod into the spark plug hole and turned the engine by hand until the rod stopped moving and stopped just before it started going downwards.

1648170380503.png


What intrigues me more is the condition of the timing belt. From the markings it seems to be a genuine OEM belt and it's definitely not new. For reference, 171k miles and no record of a timing belt job. I don't have enough experience to know whether this belt is original or not. It has printing and some lines on it but they are fading and there are small cracks on the side of the belt.

The thing that concerns me is the slop in the belt between the cam gears. I took a video of me pressing on it which I can attach if I can figure out a good way to do it. Does anyone know what is generally considered acceptable for timing belt "slop" or "give" between the gears? There is enough slop that I can slide the belt back and forth across the teeth.

I've attached some photos of the belt, but it's hard to see the details of it's condition.

I knew I would need to do a timing job eventually. If it was replaced around 100k miles, it could presumably be about time for a new one, but I'm a lot less concerned about ~71k miles on it than 171k miles. What do you guys think, based on the photos? Is there any way to know other than to disassemble further?

I don't know how exactly this plays into my sound, but I can imagine that if the belt is original, so are all of the tensioners and the water pump and who knows what else.

PXL_20220324_220608156.jpg
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I think it's entirely possible that your T-belt has never been changed.
A lot of people have no idea about the timing belt and many just sell their car when it's time to change the belt because they don't want to spend the money to replace it.

The slop on the gears is kinda normal, but your belt may be stretched as well.
The cams are kinda spring-loaded and want to sit at a spot that doesn't have the timing completely lined up.

The only pressure pulling the belt tight on the left is the pressure from the little spring on the Tensioner pulley and the pressure of the valve springs is much greater.

That's why you have to do this when you change your Timing-Belt.


Screenshot_20220325-132205_DuckDuckGo.jpg


The cams won't stay in alignment with the belt off.
One guy had a special cam tool to hold the cams still but it was made of plastic and there was enough pressure from the valve springs to bend the plastic tool.

If your Timing-Belt is stretched along with worn teeth, your valve timing may be lagging behind.
Your ignition timing should be OK though because the cam sensor let's the ECU know exactly where the cams are.
 
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Don't know if you saw it in the other thread "what did you do today" the harmonic balancer slipping and ruining the timing mark alignment but don't forget that part lol. and mine had the same belt on it at 228k so I am thinking maybe prev owner had it done at a dealer or used exact oem. also, the pic above, while I tried that the two wrenches fell off and I lost timing anyway. it was actually easy as cake to re align those up, just took some dexterity 😂. my problem came from the crank moving when getting the belt back on that one. but, hell, my timing may have been correct the first time as I noted low compression on one cyl until I gave up and just sent it after the fifth time setting timing.

As far as the slop, I observed the same on mine but noted that has a lot to do with how the engine lands when it stops, if you slowly rotate the engine the slop may go away as the belt pulls the E and I cam. at possibly 71k miles it is around the interval for a belt and if you see any cracking on the belt it's time. it's not a bad job and for me I could have done it in half a day if it weren't for the compression problems I got. prob a piece of rtv fell down into my spark plug tube. if you are lucky the prev owner also used a metal gasket for the water pump which saves time on prep for the new one. ooohh one more thing, DON'T crank the engine without the valve cover. even cranking is enough to make an oil fountain. I found out the hard way when checking for compression.
 
As far as the slop, I observed the same on mine but noted that has a lot to do with how the engine lands when it stops, if you slowly rotate the engine the slop may go away as the belt pulls the E and I cam
Yes, I did notice this, which curbed my concern a bit.

at possibly 71k miles it is around the interval for a belt and if you see any cracking on the belt it's time.
Yeah, the problem here is that I don't know if that's accurate. I will probably keep driving the car until summer when I can replace the timing belt while I'm also replacing the clutch and motor mounts. Still have no clue what that noise is though.

ooohh one more thing, DON'T crank the engine without the valve cover. even cranking is enough to make an oil fountain. I found out the hard way when checking for compression.
I'm really glad you mentioned this. I have heard of people running engines without the valve covers on, and while I would assume it would be messy, I didn't think it could be THAT messy. I was on the fence about it while I had the valve cover off but definitely glad I didn't and I know better now.

Anyways thanks for the feedback you guys, it's very helpful as always.
 
oh yeah, it shot up and got the hood with the oil, it wasn't a lot of volume just a good strong stream lol. I've def got good oil pressure 😆
 
I had an oil change done waaay back when I first got my car and they forgot to put the oil cap back on.

After less than 10 minutes of driving, there was smoke rising from under my hood.

I went back to the shop and they found the entire engine bay soaked in oil.

That was from just having the oil cap missing.
 
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