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6 hours from home, intermittent popping coming from feet area

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Hey folks,

 

 So I finished my EJ22 swap into my '92 Loyale, and hit the road. Thankfully for me, I'm on my way back...  Just have to say, for a motor that had 230k miles, power is great. But I think the rings are bad, being that I'm having to replace oil if I travel at rpm's above 3k...

 

But, my DILEMA! While driving at sustained interstate speeds, there is an intermittent popping/thudding coming from the floor near the gas pedal and the passenger's left foot. You can hear it, and if you put your hand as far up under the dash by the gas pedal, and also by the passenger's left foot.. You can feel the thumping. It feels like something his flapping around and hitting the shell of the car... 

 

 I have already gotten under it. There's nothing hanging/loose. I started trying to move everything/anything I could get my hands on. Everything feels fine. Nothing wiggly/jiggly.

 

 The noise reminds me of the first few corn kernels that start to pop when making your own popcorn. Just kinda sporadic. 

 

 The vehicle is performing well. No error codes. Fuel economy is in the low 30's right now. No problem accelerating up a hill, All gears work, although I think that the synchronizing gear for third is beginning to ware.

 

 I've been trying to trigger/kill the sound. I hear it after sustaining speeds, then if I downshift it'll stay through each gear until I'm about ready to come to a complete stop/put transmission in neutral. I tried taking it out of gear and coasting for a while. Makes it go away for about ten-20 minutes of high speed . BUT, at the same time, I experimented with a coast-to-stop as soon as I heard it next. Well I kept it in neutral, and revved it up and down while coasting. The sound/thump/pop would start and fade.

 

 Doesn't happen in City traffic. 

 

Also noticed that my speedometer has to catch up sometimes while hitting interstate speeds..

 

 

 I was wondering if the coolant lines could be popping? I feel like it's in the same area as the heater core as well? Could there be an air bubble in the system? I've had to replace about 3oz of coolant every so often since putting the motor in. No white smoke.

 

Any advice or help would be greatly appreciated.

 

 

Greg

 

 

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I get a shudder from my clutch sometimes when it slips, the speedo does what you describe at the same time.  not a poping noise, more of a deep vibration but it does have some noise and vibrates by the firewall.  its mostly solid but if I give it a little too much gas it will shudder and slip a bit.

 

I have also had that feeling and noise come from a CV axle.  Mine was under acceleration but maybe yours is worn different.

 

if your 4wd check drivelines and ujoints.

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Makes me think of a couple of things.

Coolant, as you said, but I've heard it make more of a whooshing noise, and something you couldn't feel.

Speedometer cable. Might want to check that out.

And the input shaft on the transmission and/or throwout bearing. Do you feel it in the shifter when it does it?
 

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You think maybe a transmission crossmember bolt is loose and the rocking of the trans under decel/accel is jiggling it around? You said you checked for loose stuff but even if you grabbed it and tried to wobble it, it probably wouldn't move...

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Makes me think of a couple of things.

 

Coolant, as you said, but I've heard it make more of a whooshing noise, and something you couldn't feel.

 

Speedometer cable. Might want to check that out.

 

And the input shaft on the transmission and/or throwout bearing. Do you feel it in the shifter when it does it?

 

I can only feel it coming from the firewall/shell area.

 

Thanks for the help!

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Alright, I made it home.

 

 First I'd like to thank all that are giving advice! Thank you.

 

Here is a "sound clip" of what I'm witnessing.   

 

I went from interstate to hilly-highway driving at the end of the trip yesterday. Went from somewhat constant, to very very sporadic. Although, I noticed that it'd feel/sound like there was more force in it while going up a hill in 5th. It (the sound) would lose some energy when I downshifted into 4th. It would stay, then completely vanish. Same thing with coasting in neutral. No noise/thumping. I even tried to coast and rev the motor. Couldn't produce it again. I'll be crawling under it again today. .

 

What are the chances that there is a piece of metal floating around in the tranny/diff? The revolutions of the gears cause the gear oil to swirl it around? Maybe it hits a gear in motion, and gets flung to the inner wall of the transmission? Would I still be

feeling that on the firewall though?

 

I was trying to remember back before the EJ swap... I do remember the speedometer lagging while accelerating during interstate speeds. Not a new symptom.

 

some folks mentioned to me that I wouldn't be able to detect bad mounts just by hand. Do I need to try and jack up the transmission?

 

Also of note, I have the "Group N" Impreza motor mounts, and a pitch stopper installed. All three points are secure.

 

Again, Thank you guys!

 

 

Greg

Edited by suprunner

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Perhaps you discovered the hard way, why not to go to the expense of installing a used engine with 230K miles on it.  And perhaps why the previous owner was finished with the car with that engine in it.  My limit would have been 100K, for an engine replacement. 

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Perhaps you discovered the hard way, why not to go to the expense of installing a used engine with 230K miles on it.  And perhaps why the previous owner was finished with the car with that engine in it.  My limit would have been 100K, for an engine replacement. 

 

 Valid point. But, I'm pretty impressed with this swap. More so than my 7MGE-into-4Runner swap. The compression numbers for this donor car were just fine. Plus, I changed all the gaskets. A couple were not OEM specific. I could be losing the oil there. Haven't noticed any puddles. That could be the sustained 3K+ rpm's causing a small leak? Or the rings have had it.  Plus, the cost that I put into it was pretty minimal to what I'm used to. I'll be moving to Boulder, CO in the next couple days. I know for sure that I can pick up a lower mileage motor and pop it in now for next to nothing. I don't think I'd even need a hoist. The previous owner had hit a deer, and thought the dented fender was too much to deal with.

 

Thanks!

 

Greg

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Mileage on the engine has nothing to do with popping noises. I have an ej22 here with well over 300k on it and it runs great. One of the most resilient EJ22's I used came out of a postal legacy which had been in service delivering mail on a rural route for 16 years.

 

Binding speedometer cable could be it. More likely it's a CV joint. I have had them start binding and making snap-crackle-pop noises on the highway, then once they cool off they work fine again. I would carefully check all the cv boots to look for small punctures where the grease could have gotten out

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If it's none of the above, maybe check the mudflaps/guards, plastic firewall bits, antenna, etc. They may be snug, but if there is a wee bit of play, perhaps a constant vibration builds up at a given speed, eventually causing the piece to wiggle just a bit. Like a tuning fork, it will only make noise at a given frequency. In your case the frequency would be made at a certain speed, or set of speeds. Just a thought!

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Mileage on the engine has nothing to do with popping noises. I have an ej22 here with well over 300k on it and it runs great. One of the most resilient EJ22's I used came out of a postal legacy which had been in service delivering mail on a rural route for 16 years.

 

Binding speedometer cable could be it. More likely it's a CV joint. I have had them start binding and making snap-crackle-pop noises on the highway, then once they cool off they work fine again. I would carefully check all the cv boots to look for small punctures where the grease could have gotten out

Would the speedometer cable be ruled out if the noise stops while coasting? I just did another canyon run (I live in boulder, co now), and the popping only happens in gear. But I still get a speed reading on the dash. . . If it dries out tomorrow, I'll be under it inspecting the cv though. The driver side cv is less than 4000 miles old. The passenger side is a bit older. I don't get any of the common knocking noises when I lock out the steering though. Is that always a consistent test?

 

Thanks,

 

Greg

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Everything you've described indicates the noise occurs most predictably when the car is in gear and generally disappears when out of gear.    It might be worth the effort to do some further investigation into the transmission. 

Edited by Dee2

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one side of the CV generally clicks when turning, and the other under straight acceleration, but that is only in "general".  lots of times CVs will cause vibrations or other noises if they arent completely F'd.  ours are just so bad so often that they fail big time and knock around.  if you have one that is just a little out of whack it could make all kinds of smaller issues like your describing.

 

not saying it is a CV for sure, but they can cause all kinds of wierd behavior.  

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Hey folks,

 

 So I finished my EJ22 swap into my '92 Loyale, and hit the road. Thankfully for me, I'm on my way back...  Just have to say, for a motor that had 230k miles, power is great. But I think the rings are bad, being that I'm having to replace oil if I travel at rpm's above 3k...

 

But, my DILEMA! While driving at sustained interstate speeds, there is an intermittent popping/thudding coming from the floor near the gas pedal and the passenger's left foot. You can hear it, and if you put your hand as far up under the dash by the gas pedal, and also by the passenger's left foot.. You can feel the thumping. It feels like something his flapping around and hitting the shell of the car... 

 

 I have already gotten under it. There's nothing hanging/loose. I started trying to move everything/anything I could get my hands on. Everything feels fine. Nothing wiggly/jiggly.

 

 The noise reminds me of the first few corn kernels that start to pop when making your own popcorn. Just kinda sporadic. 

 

 The vehicle is performing well. No error codes. Fuel economy is in the low 30's right now. No problem accelerating up a hill, All gears work, although I think that the synchronizing gear for third is beginning to ware.

 

 I've been trying to trigger/kill the sound. I hear it after sustaining speeds, then if I downshift it'll stay through each gear until I'm about ready to come to a complete stop/put transmission in neutral. I tried taking it out of gear and coasting for a while. Makes it go away for about ten-20 minutes of high speed . BUT, at the same time, I experimented with a coast-to-stop as soon as I heard it next. Well I kept it in neutral, and revved it up and down while coasting. The sound/thump/pop would start and fade.

 

 Doesn't happen in City traffic. 

 

Also noticed that my speedometer has to catch up sometimes while hitting interstate speeds..

 

 

 I was wondering if the coolant lines could be popping? I feel like it's in the same area as the heater core as well? Could there be an air bubble in the system? I've had to replace about 3oz of coolant every so often since putting the motor in. No white smoke.

 

Any advice or help would be greatly appreciated.

 

 

Greg

 

Get a louder sound system?

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Get a louder sound system?

 

I've tried that... I think I have small bouts of an obsessive disorder... Mainly happens when there are noises in my vehicles. I just gotta get them.

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Everything you've described indicates the noise occurs most predictably when the car is in gear and generally disappears when out of gear.    It might be worth the effort to do some further investigation into the transmission. 

I'm with you. What is there that I can do for transmission investigation? Pull it out, and tear it apart?

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If it's none of the above, maybe check the mudflaps/guards, plastic firewall bits, antenna, etc. They may be snug, but if there is a wee bit of play, perhaps a constant vibration builds up at a given speed, eventually causing the piece to wiggle just a bit. Like a tuning fork, it will only make noise at a given frequency. In your case the frequency would be made at a certain speed, or set of speeds. Just a thought!

The symptoms are mainly sporadic, while in gear only. It doesn't have a preference for speed either.

 

Thanks for your help!

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I'd like to thank all that have been contributing advice! I haven't been able to make an update, since I've been working non-stop for the past couple weeks.

 

 I started noticing a thudding noise in the driver side front wheel.

 

     A bit of back history: When I first bought the car in 2008, the driver side CV axle was torn. I replaced it. This was probably my first "extensive" vehicle repair that I had ever performed. . . That being said, I didn't correctly torque the castle nut. Drove around with some squealing/whining for a couple of days before I figured out that it hadn't been torqued enough. Well, the bearings must've taken a beating. Las year, I had the Knuckle rebuilt (new bearings pressed in by a shop)... My friend finished the install while I was out for work. While he was installing, he tore the CV boot. Fortunately he purchased a new one and installed. BUT, he didn't torque the castle nut correctly either (I was too stupid, and didn't check is work). So, this culminated in some odd clicking, and wobble noise coming from that wheel. . . The Popping/thudding noises from the firewall area still persisted at this point.

 

 I gave a call to Retro Roo. I was under the suspicion that the spacer/cone under the castle nut were trashed. Also, that the hub was going. The very helpful fellow said that that could also be the culprit for the firewall phantom... I believe his theory was referencing a possible hub failure, and the popping was the differential quickly supplying power back/forth to the wheels...

 

 Well, I changed the spacer/cone/hub. No more noises from the wheel! BUT, the popping from the firewall area still persists.. .  Going back to my theory that something might be floating around in the transmission, I popped the plug and drained it hoping for a large tooth to drop out (Also of note, the last transmission oil change was about 15K miles ago... ).Nothing of the sort. The plug had maybe a 1/16" of shavings on it. The oil looked dark though, and after draining the collection pan, there were sediments in the bottom... (see attached files)

 

 Is it time for a transmission swap? 238k on it. What are my options? I have the push-button/On-demand style 4WD, but have always been envious of the dual range Hi/low option... Are there "better" transmissions? Would one from a Legacy work? Or would I forfeit the two wheel drive for AWD?

 

Again, Thank you for your help!

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I certainly wouldnt jump all the way to a faulty transmission if its only a random thunk noise and no other issues, vibrations, or indications of slipping/binding.

 

take a break and recheck everything.  Im betting your just missing something.

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I would take it to a transmission shop and have them test drive it just to see what their opinion is.  You don't have to buy their work but it sometimes helps to get an outside opinion..

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