Installed new motor mounts; bad noise at accel. start
10-13-2012, 02:54 PM
#1
Installed new motor mounts; bad noise at accel. start
So I just installed some of the RX8 performance motor mounts in my 2005 RX8. I also did an oil change while I was at it because I had a bad oil leak. Turns out, if advanced auto parts tells you they have 1 that fits thats not OEM... dont take it, because thats what I did, and it leaked until I put an oem plug and washer in.
Anyways, I put in the mounts and this is my problem. I noticed right away that when I'd put it into first, and step on the gas and try to go, i felt a lot of vibration on the gas pedal, and a bit more than usual of transmission noises.
I drove it around for a bit thinking maybe everything had to "reseat" itself after being lifted a bit. It did get better as I drove on, but this 1 problem still persists when you first hit the gas pedal.
Well when I got home, I put the car in neutral and realized that even when the car is in neutral, when you step on the gas, the first fraction of a second that the RPMs are about to go up at, you hear a weird noise. I dont really know how to describe it other than its like something catching on something. Once you get above that small blip, it sounds ok but i can tell its not 100% normal. I feel like theres resistance on the car, its not as fast as it was, and I can feel vibration in my foot when I'm pushing down the gas pedal.
I know I didn't lift the engine too far up because I literally only lifted it up high enough to barely get the OEM mounts off. And the idle and everything is actually much smoother than it was; so it feels like the mounts are working.
I'm not sure if it's unrelated or not, but when I got in, there was a bit of a strange smell coming from the passengers side under the hood. Around the part of the engine that I think is the fuel injection/mixing with air portion.
What's up with this?
Anyways, I put in the mounts and this is my problem. I noticed right away that when I'd put it into first, and step on the gas and try to go, i felt a lot of vibration on the gas pedal, and a bit more than usual of transmission noises.
I drove it around for a bit thinking maybe everything had to "reseat" itself after being lifted a bit. It did get better as I drove on, but this 1 problem still persists when you first hit the gas pedal.
Well when I got home, I put the car in neutral and realized that even when the car is in neutral, when you step on the gas, the first fraction of a second that the RPMs are about to go up at, you hear a weird noise. I dont really know how to describe it other than its like something catching on something. Once you get above that small blip, it sounds ok but i can tell its not 100% normal. I feel like theres resistance on the car, its not as fast as it was, and I can feel vibration in my foot when I'm pushing down the gas pedal.
I know I didn't lift the engine too far up because I literally only lifted it up high enough to barely get the OEM mounts off. And the idle and everything is actually much smoother than it was; so it feels like the mounts are working.
I'm not sure if it's unrelated or not, but when I got in, there was a bit of a strange smell coming from the passengers side under the hood. Around the part of the engine that I think is the fuel injection/mixing with air portion.
What's up with this?
10-13-2012, 03:24 PM
#2
Zoom Frickin Zoom
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are you 100% sure you tightened the bolt/nut that holds the mount to the mount arm? you have to have an Allen wrench in the bottom of the mount and tighten the nut on top BEFORE you bolt it to the frame rail. It sounds like something is not tightened down right, or you dont have the washers in correctly. There should be one on either side of the urethane bushing.
10-13-2012, 03:57 PM
#4
so I put them in, and there is 1 small washer inbetween the nut and the arm, and then 1 bigger washer inbetween the mount and the bar.
I actually re-lifted it this morning because I was worried about having the bolt that goes on the arm too lose.
I put an allen wrench on the bottom of the mount in that opening, and used a socket wrench on the nut. I got it tight enough to the point where if you used your hand, you can still decently twist it left or right but there is some good resistance. If you grab the nut, you can still spin the whole bolt though. Is it supposed to be even tighter than that?
My worry was that I damaged a connection between the engine and the crankshaft (by jacking the motor up) which is why its making that weird noise when starting to accelerate.
I guess I can try the process over again. But it is pretty snug.
I actually re-lifted it this morning because I was worried about having the bolt that goes on the arm too lose.
I put an allen wrench on the bottom of the mount in that opening, and used a socket wrench on the nut. I got it tight enough to the point where if you used your hand, you can still decently twist it left or right but there is some good resistance. If you grab the nut, you can still spin the whole bolt though. Is it supposed to be even tighter than that?
My worry was that I damaged a connection between the engine and the crankshaft (by jacking the motor up) which is why its making that weird noise when starting to accelerate.
I guess I can try the process over again. But it is pretty snug.
10-13-2012, 05:21 PM
#6
I'm not sure, I will check tomorrow. I may try relifting it and tightening the nuts more. If you look at the nuts at a perfectly straight plain, you can see 2 rings/threads of the screw coming out the top of the nylock nut.
You deffinitely can spin it freely. Maybe I didnt tighten it down all the way?
Whats weird though is every time I drive it, it seems to get less noticeable. I just drove it, and I can only tell when I am in first gear trying to creep. Its the 800-1000 RPM range where it just vibrates and makes a weird metal on metal sound. But still, driving it I feel like theres just vibration in the gas pedal.
I'll try reseating it tomorrow and see what happens. I know you'd think I'm an idiot, but where can I locate the drive shaft? and how could I possibly remedy that situation? That'd be a new area for me.
You deffinitely can spin it freely. Maybe I didnt tighten it down all the way?
Whats weird though is every time I drive it, it seems to get less noticeable. I just drove it, and I can only tell when I am in first gear trying to creep. Its the 800-1000 RPM range where it just vibrates and makes a weird metal on metal sound. But still, driving it I feel like theres just vibration in the gas pedal.
I'll try reseating it tomorrow and see what happens. I know you'd think I'm an idiot, but where can I locate the drive shaft? and how could I possibly remedy that situation? That'd be a new area for me.
10-13-2012, 05:41 PM
#7
If the nuts are tight.....Take the car out and turn it hard side to side a couple of times to seat the engine/tranny into a stable position. Then see if you can still hear the noise.
If you can...look at the back of the transmission and see if there is any sign of things rubbing that will cause the noise....look for any thing that rubs on any of the heat sheilds
Check to see that this isn't a belt or an engine noise as well...not sure what to say other than that..
Maybe make sure the stock alum brackets are secured to the engine block as well??
If you can...look at the back of the transmission and see if there is any sign of things rubbing that will cause the noise....look for any thing that rubs on any of the heat sheilds
Check to see that this isn't a belt or an engine noise as well...not sure what to say other than that..
Maybe make sure the stock alum brackets are secured to the engine block as well??
10-13-2012, 06:46 PM
#8
I'm not sure, I will check tomorrow. I may try relifting it and tightening the nuts more. If you look at the nuts at a perfectly straight plain, you can see 2 rings/threads of the screw coming out the top of the nylock nut.
You deffinitely can spin it freely. Maybe I didnt tighten it down all the way?
You deffinitely can spin it freely. Maybe I didnt tighten it down all the way?
10-14-2012, 12:20 PM
#10
Small washer on top of arm, large one below. The point is to get some compression on the delrin, but not too much. If the noise is starting to go away, perhaps the long bolt is not centered in the hole through the arm and there is an aluminum/steel rub. The pic shows the washers. Also note, I had to sand away a bit of the base near the lower bolt to get things to center "naturally". There is some variation between cars in exactly how the engine sits.
Last edited by HiFlite999; 10-14-2012 at 12:26 PM.
10-14-2012, 06:59 PM
#11
Ok, so today I relifted it up. I didnt take them out, but I tightened both of the nuts until it was quite difficult to rotate the mount, but not impossible either. I dropped the motor down, tightened everything up, and took it for a spin. The result? Issue was even worse. It's very strange. When the car is warmed up, my RPMS drop to about 700-800 for idle. Its super smooth. But for some reason, 1.1 RPMs is where the problem is. And i literally mean, THAT RPM.
If you rev the motor up, and let it drop, it stops for a second at 1.1 RPMs and does the vibration thing, and then drops to a smooth idle.
When I push in the gas slightly, it does the same thing. If I try to hold the pedal at 1.1k RPMs, I can hear that I think its coming from the passengers side of the car. It vibrates and my glove box makes a god awful rattle. When I accelerate above that, I can tell that the intense vibration/catching isnt there, but there is resistance. I know this because my car isnt accelerating as fast as it used to. I'm starting to think maybe its something else.
What's kind of funny is though, the first time I had the issue; I went out and drove it this morning before redoing everything, and it was 50% better. It wasnt nearly as much vibration as yesterday, and I didnt feel the resistance as much. I only relifted and started over because I wanted to do it right.
If you rev the motor up, and let it drop, it stops for a second at 1.1 RPMs and does the vibration thing, and then drops to a smooth idle.
When I push in the gas slightly, it does the same thing. If I try to hold the pedal at 1.1k RPMs, I can hear that I think its coming from the passengers side of the car. It vibrates and my glove box makes a god awful rattle. When I accelerate above that, I can tell that the intense vibration/catching isnt there, but there is resistance. I know this because my car isnt accelerating as fast as it used to. I'm starting to think maybe its something else.
What's kind of funny is though, the first time I had the issue; I went out and drove it this morning before redoing everything, and it was 50% better. It wasnt nearly as much vibration as yesterday, and I didnt feel the resistance as much. I only relifted and started over because I wanted to do it right.
10-14-2012, 08:02 PM
#12
The mounts are definitely stiffer than stock. There is more noticeable vibration at low rpm, requiring more finesse with the clutch when taking off. What's going on may fall into the "no free lunch" category. You can't get stiffer mounts without somewhat more vibration coming into the cabin. If that's causing sympathetic rattles somewhere, it's not too surprising. If the acceleration is less than before, it's hard to see how that could be due to engine mounts.
10-15-2012, 09:16 AM
#14
@Hifilite9999:
Yeah. I'm beginning to think maybe thats possibly a bit of whats going on. Reason is, is because with the OEM mounts it would be semi-smooth and then be like a nickel in a tin can once it got warm. Now super smooth while cool, and then that issue I'm having gets worse as the motor warms up. I'll drive it for a few days and see how it feels. But maybe you're right. Maybe I just was expecting something different from the mounts.
@dannobre:
I put the front up on the highest setting on my jack stands (because atm thats all I have as far as jacking goes), and I really cant see crap. From what I can see, I can't see anything damaged/rubbing. If the problem persists and I feel like it isnt normal, I'll bring it to a mechanic to check out.
Thanksfor the advice all. You know what is kind of depressing though? after all of this, I was hoping it would solve the annoying problem I was looking to fix; My shifter **** vibrating. Still vibrates quite a bit. oh well lol.
Yeah. I'm beginning to think maybe thats possibly a bit of whats going on. Reason is, is because with the OEM mounts it would be semi-smooth and then be like a nickel in a tin can once it got warm. Now super smooth while cool, and then that issue I'm having gets worse as the motor warms up. I'll drive it for a few days and see how it feels. But maybe you're right. Maybe I just was expecting something different from the mounts.
@dannobre:
I put the front up on the highest setting on my jack stands (because atm thats all I have as far as jacking goes), and I really cant see crap. From what I can see, I can't see anything damaged/rubbing. If the problem persists and I feel like it isnt normal, I'll bring it to a mechanic to check out.
Thanksfor the advice all. You know what is kind of depressing though? after all of this, I was hoping it would solve the annoying problem I was looking to fix; My shifter **** vibrating. Still vibrates quite a bit. oh well lol.
10-15-2012, 11:52 AM
#16
. Not a huge deal, just one of those things. Cant have your cake and eat it too. I think what I may do is when I get home Ill make a short video. Ill show the shifter, Ill also put the camera next to the passenger side and everything. Maybe you can get a better idea. My explanation isnt doing you any good i think.
10-16-2012, 09:44 AM
#18
So a small update on the issue. I believe that it is just a matter of breaking the mounts in or letting everything seat itself back.
This morning when I drove to work, it drove perfectly normal while cold, and I started experiencing the vibrate problem once the engine got warm (still only at 1.1k RPMs). It wasnt as bad though. I will drive it for a few more days and hopefully the issue will go away.
One thing that I find that is strange and I will one day take a video of it is, when my car is cold, my Tach doesnt really even go down to 1.1k rpms. It stays a bit above it until the engine warms up on idle. If I were to rev the needle up to 4k RPMS or so, cold I would see a slow drop to around 1.2-1.3 or wherever the idle point is at that time. No vibration/weird noises. Once it gets hot, If I rev it to 6-7k at idle, You'll see the needle drop quite quickly to 1.1k and then it will vibrate horribly, and you'll see the needle bounce back up to around 1.2k-1.3.K RPMS, like it just hit an invisible bouncy ball, and then drop back down to like 700-800RPMS and be super smooth.
Isnt that strange?
Well, hopefully it will keep improving like it has been.
Now my issue will be my passenger side front tire. I keep having to pump it up. Loses about 4-5PSI every 3-4 days as its getting cold here. Must have a small leak
. I keep pumping it to 30 and 3 days later my sensor goes off and its at 25-26.
Anyways, thanks for the advice guys Ill keep letting you know.
Cheers
This morning when I drove to work, it drove perfectly normal while cold, and I started experiencing the vibrate problem once the engine got warm (still only at 1.1k RPMs). It wasnt as bad though. I will drive it for a few more days and hopefully the issue will go away.
One thing that I find that is strange and I will one day take a video of it is, when my car is cold, my Tach doesnt really even go down to 1.1k rpms. It stays a bit above it until the engine warms up on idle. If I were to rev the needle up to 4k RPMS or so, cold I would see a slow drop to around 1.2-1.3 or wherever the idle point is at that time. No vibration/weird noises. Once it gets hot, If I rev it to 6-7k at idle, You'll see the needle drop quite quickly to 1.1k and then it will vibrate horribly, and you'll see the needle bounce back up to around 1.2k-1.3.K RPMS, like it just hit an invisible bouncy ball, and then drop back down to like 700-800RPMS and be super smooth.
Isnt that strange?
Well, hopefully it will keep improving like it has been.
Now my issue will be my passenger side front tire. I keep having to pump it up. Loses about 4-5PSI every 3-4 days as its getting cold here. Must have a small leak
. I keep pumping it to 30 and 3 days later my sensor goes off and its at 25-26. Anyways, thanks for the advice guys Ill keep letting you know.
Cheers
10-16-2012, 05:33 PM
#19
Your idle speed issue is normal....when the engine is hot it idles faster to make sure it stays running. When the motor is cold it will also limit your RPM so that the engine won't be damaged till it warms up.
What isn't normal is the "hiccup" you are getting.
You should take it out and drive it hard for a while to let it heat things up well...and then see if it idles better.
When did you replace plugs, coils, wires last? This car is hard on the ignition components
What isn't normal is the "hiccup" you are getting.
You should take it out and drive it hard for a while to let it heat things up well...and then see if it idles better.
When did you replace plugs, coils, wires last? This car is hard on the ignition components
10-16-2012, 08:24 PM
#20
Your idle speed issue is normal....when the engine is hot it idles faster to make sure it stays running. When the motor is cold it will also limit your RPM so that the engine won't be damaged till it warms up.
What isn't normal is the "hiccup" you are getting.
You should take it out and drive it hard for a while to let it heat things up well...and then see if it idles better.
When did you replace plugs, coils, wires last? This car is hard on the ignition components
What isn't normal is the "hiccup" you are getting.
You should take it out and drive it hard for a while to let it heat things up well...and then see if it idles better.
When did you replace plugs, coils, wires last? This car is hard on the ignition components
I replaced all 3 at the same time about 4-5 months ago. I cant say that the plugs arent worn because of the not-starting issue i had when that bolt was loose on the starter. It was flooded pretty good until I did the de-flood.
Regardless it's not right that the ignition would "suddenly" cause this problem after changing the motor mounts.
Here are 2 quick videos I took. I realized once I uploaded them that it just doesnt do it justice. You can hear the hiccup and see the TAC. But thats about it. In the second video I just wanted to show you the motor mount as I was giving it gas so you can see that it is bolted down tight and not shaking all over the place. In the first video its just a few seconds of my tach inside the cabin and then next to the front passenger side wheel where I could hear the sound coming from inside the cabin.
Vid 1
Vid 2
10-17-2012, 10:44 AM
#21
Scott from rx8 performance where I bought the mounts actually gave me a courtesy call this morning and said that the vibrating I am feeling on the mounts may be due to an adjustable portion between the rear differential and transmission. I'm at work right now so I cant really look up exactly what the name of it is, but he thinks that will fix the mild vibration.
However that does not fix my hiccup I am having when the car gets hot. I drove it cold today and it was fine. No issues. Once it gets warm though, its just that 1 spot, 1.1k RPMs.
I didnt know if I should mention this before or not because I didnt want posters' minds fixed on this because I had music playing in the background while doing this process. The first time I jacked my motor up, I heard a loud crack from where I was jacking the motor up. I figured it was the 2x4 because the 2x4 I was using was bigger than the oil pan and got caught inbetween the crossmember and another piece.
Maybe I damaged something? It just seems strange though. I did it correctly and went very slowly and did NOT overraise the motor. So I really didnt think much of it. Any ideas on possible pieces of equipment that are connected to the motor that may have cracked? Could a crack to motor possibly have happened causing this issue?
I tried looking underneath and I really just cant see anything damaged. and it boggles my mind that this issue only happens when the car is warm enough to idle under 1000 RPMS and it is super smooth until I just inch the gas, and it has the issue until you get above 1.1k
However that does not fix my hiccup I am having when the car gets hot. I drove it cold today and it was fine. No issues. Once it gets warm though, its just that 1 spot, 1.1k RPMs.
I didnt know if I should mention this before or not because I didnt want posters' minds fixed on this because I had music playing in the background while doing this process. The first time I jacked my motor up, I heard a loud crack from where I was jacking the motor up. I figured it was the 2x4 because the 2x4 I was using was bigger than the oil pan and got caught inbetween the crossmember and another piece.
Maybe I damaged something? It just seems strange though. I did it correctly and went very slowly and did NOT overraise the motor. So I really didnt think much of it. Any ideas on possible pieces of equipment that are connected to the motor that may have cracked? Could a crack to motor possibly have happened causing this issue?
I tried looking underneath and I really just cant see anything damaged. and it boggles my mind that this issue only happens when the car is warm enough to idle under 1000 RPMS and it is super smooth until I just inch the gas, and it has the issue until you get above 1.1k
10-17-2012, 11:23 AM
#22
Zoom Frickin Zoom
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Scott from rx8 performance where I bought the mounts actually gave me a courtesy call this morning and said that the vibrating I am feeling on the mounts may be due to an adjustable portion between the rear differential and transmission. I'm at work right now so I cant really look up exactly what the name of it is, but he thinks that will fix the mild vibration.
However that does not fix my hiccup I am having when the car gets hot. I drove it cold today and it was fine. No issues. Once it gets warm though, its just that 1 spot, 1.1k RPMs.
I didnt know if I should mention this before or not because I didnt want posters' minds fixed on this because I had music playing in the background while doing this process. The first time I jacked my motor up, I heard a loud crack from where I was jacking the motor up. I figured it was the 2x4 because the 2x4 I was using was bigger than the oil pan and got caught inbetween the crossmember and another piece.
Maybe I damaged something? It just seems strange though. I did it correctly and went very slowly and did NOT overraise the motor. So I really didnt think much of it. Any ideas on possible pieces of equipment that are connected to the motor that may have cracked? Could a crack to motor possibly have happened causing this issue?
I tried looking underneath and I really just cant see anything damaged. and it boggles my mind that this issue only happens when the car is warm enough to idle under 1000 RPMS and it is super smooth until I just inch the gas, and it has the issue until you get above 1.1k
However that does not fix my hiccup I am having when the car gets hot. I drove it cold today and it was fine. No issues. Once it gets warm though, its just that 1 spot, 1.1k RPMs.
I didnt know if I should mention this before or not because I didnt want posters' minds fixed on this because I had music playing in the background while doing this process. The first time I jacked my motor up, I heard a loud crack from where I was jacking the motor up. I figured it was the 2x4 because the 2x4 I was using was bigger than the oil pan and got caught inbetween the crossmember and another piece.
Maybe I damaged something? It just seems strange though. I did it correctly and went very slowly and did NOT overraise the motor. So I really didnt think much of it. Any ideas on possible pieces of equipment that are connected to the motor that may have cracked? Could a crack to motor possibly have happened causing this issue?
I tried looking underneath and I really just cant see anything damaged. and it boggles my mind that this issue only happens when the car is warm enough to idle under 1000 RPMS and it is super smooth until I just inch the gas, and it has the issue until you get above 1.1k
On the cracking noise, I would check the air pump tube and brackets, basically the whole air pump system. I havent had that system in years but if I recall the pump is connected to the exhaust manifold by a metal tube, that could be what you heard.
On your tyre issue, if you dont have anything in it, (like a nail) your air valve on the tps may be leaking. They need to be rebuilt every now any then; a tyre shop SHOULD offer this when you get new tyres.
10-17-2012, 01:52 PM
#23
on the idle, You can always try cleaning your throttle body, sometimes if it gets gunked up it could cause something similar..
On the cracking noise, I would check the air pump tube and brackets, basically the whole air pump system. I havent had that system in years but if I recall the pump is connected to the exhaust manifold by a metal tube, that could be what you heard.
On your tyre issue, if you dont have anything in it, (like a nail) your air valve on the tps may be leaking. They need to be rebuilt every now any then; a tyre shop SHOULD offer this when you get new tyres.
On the cracking noise, I would check the air pump tube and brackets, basically the whole air pump system. I havent had that system in years but if I recall the pump is connected to the exhaust manifold by a metal tube, that could be what you heard.
On your tyre issue, if you dont have anything in it, (like a nail) your air valve on the tps may be leaking. They need to be rebuilt every now any then; a tyre shop SHOULD offer this when you get new tyres.
Thank you for the advice. I will check all of these. I'm actually almost tempted to put back in my old motor mounts to see if the issue is still there you know? But I will check all of those components tomorrow.
That way I know that it was just something I broke while jacking up the motor. I do want to stress though, it is not literally "idle" which is the issue. It's very hard to describe but it is "right above" idle. idle is super smooth. It's only when you hit the gas a slight bit does it vibrate/buzz/knock/ whatever you want to call it.
10-19-2012, 07:06 AM
#24
So I put my car on a hoist, had my wife consistently lightly press the gas where I ran around and poked my head in everywhere. the only thing I could see that seemed like it could be causing this issue, is the (and i dont know the exact name) pipe that seems to be the beginning of the exhaust system. It runs inbetween the passenger motor and the mount, and the bracket that connects the 2 over it. So basically its surrounded on 3 sides, and its tight.
The motor mount on the passenger side has a pretty dramatic lean in towards the motor. I cant really do much about it though seeing as everything is bolted down very tight.
What I'm thinking though is that the pipe is vibrating, and hitting/rubbing on whats surrounding it.
Any ideas from any one on how to correct this issue? (Also, I'm not even sure if this is whats causing it. A local mechanic said it deffinitely sounds like a rubbing noise). He said if I cant find the source he'll put it on a lift and help me look.
Any thoughts?
The motor mount on the passenger side has a pretty dramatic lean in towards the motor. I cant really do much about it though seeing as everything is bolted down very tight.
What I'm thinking though is that the pipe is vibrating, and hitting/rubbing on whats surrounding it.
Any ideas from any one on how to correct this issue? (Also, I'm not even sure if this is whats causing it. A local mechanic said it deffinitely sounds like a rubbing noise). He said if I cant find the source he'll put it on a lift and help me look.
Any thoughts?