Well not really, only on 2 of the plugs and each pack had to run one other plug.
I did it again!
- Thread starter 6speed
- Start date
Well not really, only on 2 of the plugs and each pack had to run one other plug.
Today I had my rear wheel bearings replaced. The left one was starting to fail, which is rare for Miatas, and when they fail they tend to come with explanations such as "LS powered" or "over 2.0 lateral Gs regularly". My only guess is that the diff problem somehow overstressed it. It's not impossible. The fronts fail regularly for tracked Miatas, which is one reason i'm planning on blueprinted hub replacements next year. 20% more than OEM hubs for 3 times the durability.
I also rewired my LS ignition, as I was running into an ignition cut problem that wasn't commanded by the ECU. Periodic stumbles, and a few times recently complete ignition shut down for 5+ seconds while on the highway. AFR gauge showed I was still going rich or lean with throttle usage, which is what told me it was an ignition failure. Well, I ended up determining that it must have been because of cheap failing quick disconnects that I had used when I was testing the Fab9 coil on plug kit, to make swapping easier. I hadn't gone back and rewired everything, and I suspect that the quick disconnects were failing. So they are all gone now, everything properly soldered, heat shrunk, and shielded. Also remounted the coils, now bolted directly to the upper side of the wheel well bulge, rather than the vibration-prone tray i had fashioned. Less "pretty", but far more stable and secure. Test firing the engine showed a much faster start than I have been dealing with as well. I will find out tomorrow if I solved the problem.
Also going in for a clutch replacement next Tuesday. This one is nearing 50,000 miles (about the expected lifespan for it), and it is slipping at peak torque, 7psi, and high gear. With this cold, even the lowest MBC setting is giving me ~8psi.
I also rewired my LS ignition, as I was running into an ignition cut problem that wasn't commanded by the ECU. Periodic stumbles, and a few times recently complete ignition shut down for 5+ seconds while on the highway. AFR gauge showed I was still going rich or lean with throttle usage, which is what told me it was an ignition failure. Well, I ended up determining that it must have been because of cheap failing quick disconnects that I had used when I was testing the Fab9 coil on plug kit, to make swapping easier. I hadn't gone back and rewired everything, and I suspect that the quick disconnects were failing. So they are all gone now, everything properly soldered, heat shrunk, and shielded. Also remounted the coils, now bolted directly to the upper side of the wheel well bulge, rather than the vibration-prone tray i had fashioned. Less "pretty", but far more stable and secure. Test firing the engine showed a much faster start than I have been dealing with as well. I will find out tomorrow if I solved the problem.
Also going in for a clutch replacement next Tuesday. This one is nearing 50,000 miles (about the expected lifespan for it), and it is slipping at peak torque, 7psi, and high gear. With this cold, even the lowest MBC setting is giving me ~8psi.
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Fixed.
Not even a stumble on the way to work, so I migh thave gotten the problem. I've got ~17 hours of driving over the next 2 weeks (not counting another 8 in someone else's car) for family stuff all over the place, so that will definitely show if i solved it or not.
Not even a stumble on the way to work, so I migh thave gotten the problem. I've got ~17 hours of driving over the next 2 weeks (not counting another 8 in someone else's car) for family stuff all over the place, so that will definitely show if i solved it or not.
The MSM's engine may be wounded ...
It almost sounds like a very faint main bearing tap. Sound wasn't there 2 days ago, was there yesterday, still full on oil with 2,200 miles on it, no high lateral g that might indicate there was an oil starvation, and nothing above 6,000rpm or 8psi. Can't hear it from the engine bay or the top of the engine, can only slightly hear it from the driver's seat with the windows up and hard top on, and can only hear it under ~1,200rpm. In time with revs, sounds like one cylinder from the rate of the noise.
I've got about 8 hours of driving by Saturday, and the Celica still isn't inspected yet, as it has a voltage problem with one headlight that blew out the bulbs that i haven't found yet.
Did an oil change already, no noise change, no metal on the magnetic plug. Cutting open the oil filter today to see if there is any metal in there. Also going to do a compression test to see if there are any low cylinders that might suggest a bent rod.
I hope i'm worrying over nothing, but... that noise wasn't there before.
It almost sounds like a very faint main bearing tap. Sound wasn't there 2 days ago, was there yesterday, still full on oil with 2,200 miles on it, no high lateral g that might indicate there was an oil starvation, and nothing above 6,000rpm or 8psi. Can't hear it from the engine bay or the top of the engine, can only slightly hear it from the driver's seat with the windows up and hard top on, and can only hear it under ~1,200rpm. In time with revs, sounds like one cylinder from the rate of the noise.
I've got about 8 hours of driving by Saturday, and the Celica still isn't inspected yet, as it has a voltage problem with one headlight that blew out the bulbs that i haven't found yet.
Did an oil change already, no noise change, no metal on the magnetic plug. Cutting open the oil filter today to see if there is any metal in there. Also going to do a compression test to see if there are any low cylinders that might suggest a bent rod.
I hope i'm worrying over nothing, but... that noise wasn't there before.
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- 92 & 16 Meyatas
oh no, lets hope not after all you have invested, time and money? i wouldn't know a main bearing tap if i heard it...you have special skilz!! go slow dude!
No metal in the oil pan or in the oil filter, so I'm thinking not a bearing or oil related problem.
Still need to do the compression test to verify even compression on all cylinders (last test were all within 5psi if i recall correctly).
This might be related to my ignition rewiring, and might be an electrical tap instead of a mechanical one. It would be a relief if so.
Still need to do the compression test to verify even compression on all cylinders (last test were all within 5psi if i recall correctly).
This might be related to my ignition rewiring, and might be an electrical tap instead of a mechanical one. It would be a relief if so.
I think i figured out what it is. I mounted the LS2 coils directly to the fender, and I think one of them is transmitting a 'tap' from the internal arcing that they do. You can feel them all pulsing slightly when the engine is on and you touch them, and one of the coils is pulsing stronger than the other 3. Going to test the theory tomorrow by seeing if the sound goes away with them just laying on a mat above the engine instead of bolted anywhere.
7 hours of driving today and yesterday, zero problems.
Compression is within 3psi of each other on all 4 cylinders, ~123psi if I were to believe my cheap compression gauge. The stability of the numbers is the main point I concern myself with.
7 hours of driving today and yesterday, zero problems.
Compression is within 3psi of each other on all 4 cylinders, ~123psi if I were to believe my cheap compression gauge. The stability of the numbers is the main point I concern myself with.
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- 2016 GT ST 47A
I'm thinking the same thing. Mike should get a nice insurance policy on those ears!
How did you make out? I hope this was the issue, a nice easy fix. Like Mark said I'd hate to see it be something catastrophic given everything you've invested.
And moving?
I do have better hearing than most people I interact with, it's always been my strongest sense.
No, that wasn't it. However, I've driven 11 hours since first hearing it, and the sound hasn't changed, the engine hasn't blown up, and today my clutch was replaced and both of the shop's engine guys sat in the car and couldn't hear anything odd.
So while I know something changed and i'm not just hearing things (because I can hear it showing up about 10 seconds after starting, it isn't there then it is), it doesn't appear to be anything related to engine operation. Dunno. Zero symptoms other than the noise.
Realistically I just need it to last a few more months, and I would be plenty happy to pull the engine and have it built.
I'm not sure what you mean by this line?
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- 2016 GT ST 47A
Indeed it is! Up at LRP this year I saw that first hand as you were diagnosing the coil issue at the gas station. Uncanny!
Sux you haven't found the issue but at least she's running ok. Fingers crossed you get those next few months of the same.
A few posts back you mentioned your wife being in MD and not coming back and getting a truck to replace the Celica which would aid in moving.
Sux you haven't found the issue but at least she's running ok. Fingers crossed you get those next few months of the same.
A few posts back you mentioned your wife being in MD and not coming back and getting a truck to replace the Celica which would aid in moving.
Ah, staying in the area, just need to downsize interior space, upsize exterior space.
MSM had a left rear tire blowout on a highway road seam pothole Friday in MD, parked it at friends of the family that happened to be a couple miles away. Picking it up and repairing tomorrow. Busy week with family.
MSM had a left rear tire blowout on a highway road seam pothole Friday in MD, parked it at friends of the family that happened to be a couple miles away. Picking it up and repairing tomorrow. Busy week with family.
So I strongly suspect that there is something indeed going on inside my engine that is unhealthy. It probably isn't a massive critical problem yet, but I expect it will become so eventually.
I'm increasingly wary and unsure of how much I can rely on it, and I am getting very close to just parking it in long term storage until I can pull the engine and send it off for an FM rebuild. I'd rather do that then keep driving it until it finally blows spectacularly, stranding me and making me have to go find a core to use for a rebuild.
I still have to drive it right now, no choice, but trying to get the Celica's electrical issue figured out so I can get that on the road.
I'm increasingly wary and unsure of how much I can rely on it, and I am getting very close to just parking it in long term storage until I can pull the engine and send it off for an FM rebuild. I'd rather do that then keep driving it until it finally blows spectacularly, stranding me and making me have to go find a core to use for a rebuild.
I still have to drive it right now, no choice, but trying to get the Celica's electrical issue figured out so I can get that on the road.
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- 92 & 16 Meyatas
And what does "mikes super ear" think is going on? You know you want an 8! ��
I don't really know. I suspect a slight tolerance shift in a crank bearing, possibly as a result of an oiling problem that I wouldn't have an explanation for without a teardown. Something isn't as smooth as it was before, and I periodically hear a noise that I only previously heard with the oil filter relocation installed. Like a faint howling of forced liquid/air through a small hole. It was louder on 20w50 than it is on 0w40, suggesting that there may be an oil restriction somewhere, perhaps one of the passages got partially clogged with something. And then perhaps that is affecting whatever it is that I'm hearing from the crank.
Perhaps perhaps perhaps. Maybe maybe. If.
Dunno.
The engine is periodically slightly raspier than it is normally, with no explanation. No exhaust leaks found.
I have a very very slight coolant loss that only occurs while the engine is running. Every few trips I notice the level in the coolant bottle will drop by about a 3rd of the bottle. No leaks found, no puddles ever left, no residue coating anything. No evidence of a head gasket leak.
Idle control is slowly getting more and more pear shaped. I suspect a problem with the idle air control solenoid, caused by the cold, but I don't really know for sure.
The rear main seal was leaking, needing a clutch replacement as a result... and I suspect that they incorrectly replaced it, since the new clutch randomly slipped against yesterday after an hour of constant driving, which is what it did before when it became oil contaminated (450 miles on the clutch). If they gouged the crank, it probably means pulling the engine and breaking it down to repair (on them, yes, but if it's open anyway...)
So yeah. It may be nothing, but I am quickly losing confidence in the engine's ability to even last till spring.
Perhaps perhaps perhaps. Maybe maybe. If.
Dunno.
The engine is periodically slightly raspier than it is normally, with no explanation. No exhaust leaks found.
I have a very very slight coolant loss that only occurs while the engine is running. Every few trips I notice the level in the coolant bottle will drop by about a 3rd of the bottle. No leaks found, no puddles ever left, no residue coating anything. No evidence of a head gasket leak.
Idle control is slowly getting more and more pear shaped. I suspect a problem with the idle air control solenoid, caused by the cold, but I don't really know for sure.
The rear main seal was leaking, needing a clutch replacement as a result... and I suspect that they incorrectly replaced it, since the new clutch randomly slipped against yesterday after an hour of constant driving, which is what it did before when it became oil contaminated (450 miles on the clutch). If they gouged the crank, it probably means pulling the engine and breaking it down to repair (on them, yes, but if it's open anyway...)
So yeah. It may be nothing, but I am quickly losing confidence in the engine's ability to even last till spring.
PCV valve has failed. And probably has been failed for some time. It would produce at least 1 of the two noises I hear, and it could also cause the rear main seal failure from a pressurized crankcase that has no other venting option.
Professional testing of my engine (compression, leakdown, cylinder inspection through plug holes, stethescope) showed that the engine itself is still healthy, so crossing my fingers that it's really just a $20 part.
Professional testing of my engine (compression, leakdown, cylinder inspection through plug holes, stethescope) showed that the engine itself is still healthy, so crossing my fingers that it's really just a $20 part.
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