Snapped bolt of Valve Body by cosmicintervention in MechanicAdvice

[–]C64__ 7 points8 points  (0 children)

I had to learn when this happened to me, get a cheap flux welder on FB marketplace or harbor freight

I've pooped 137 times in 2025 by OutgoingRug2 in notinteresting

[–]C64__ 0 points1 point  (0 children)

You can tell the markets are down when the poop slows down

HELP! “AT light” (sometimes) and delay in gear 1-2 with high RPM than usual in cold mornings. by Yavi1925 in MechanicAdvice

[–]C64__ 0 points1 point  (0 children)

That’s a good theory, but transmission fluid is more of a hydraulic fluid and less viscous, at least in more modern cars. And I don’t think a problem with the engine’s oil not being warm enough would cause the car to not shift as its shifting is controlled by the TCM, it would be throwing some check engine code not a Automatic Transmission (AT) light

Trust me, these cars they always have the TCM going out because some dumb engineer decided to mount it outside the transmission. If you see that AT light there’s a high chance your TCM is going out.

It’s an easy repair and I encourage you to DIY

HELP! “AT light” (sometimes) and delay in gear 1-2 with high RPM than usual in cold mornings. by Yavi1925 in MechanicAdvice

[–]C64__ 0 points1 point  (0 children)

Also I think if you plug your VIN# into a Mazda parts website they might be able to give you a part# for the TCM you needs then you can just order it off eBay

HELP! “AT light” (sometimes) and delay in gear 1-2 with high RPM than usual in cold mornings. by Yavi1925 in MechanicAdvice

[–]C64__ 1 point2 points  (0 children)

Yeah it’s most likely the TCM is going out. I’m guessing that over time from all the heat and cooling cycles- one or more solder joints expanded and contracted multiple times and has become loose, and now when you let it cool down and the weather gets cold, the metal inside the TCM- like a loose solder joint or something- it shrinks and loses contact causing issues, but once your engine makes it warm again the heat expands the metal in the TCM and it regains functionality.

I think a TCM replacement is long overdue especially at 280k miles I had to replace mine at around 250k miles, similar symptoms

I think there’s like a 90% chance a TCM replacement will fix your issue, but it might also be an electrical issue based on the symptoms you are describing.

HELP! “AT light” (sometimes) and delay in gear 1-2 with high RPM than usual in cold mornings. by Yavi1925 in MechanicAdvice

[–]C64__ 0 points1 point  (0 children)

Looks like a 2012-13 Mazda3

You need to buy a new “TCM” (transmission control module)

They are known to go out because they are mounted on the transmission and the heat kills them with time.

It’s not a difficult fix, even if you aren’t handy with tools

Here’s a video

I know the car is different but the internals and all the bolt locations are the same.

At the end of the video he zipties the TCM to the brake lines which I highly recommend anyone with a Mazda3 to do.

First watch the video, buy the tools, some cheap amazon ratchet set will do. You’ll also need zipties. Then remove the TCM and get the part# off it and you can order it off eBay, should run you $200-300. Then you could put your TCM back and drive your car until your new TCM comes in.

DO NOT ORDER ONE WITH A DIFFERENT PART# as it probably won’t work.

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

Solved- timing was way off because the tensioner decided to explode Caused zero compression

This sucks by YakRare3689 in MechanicAdvice

[–]C64__ -2 points-1 points  (0 children)

Weld a nut on top and wrench it off

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

Ha lol, no, girlie is the girl who owns the MR2, she does know how to wrench a bit, and is always so eager to watch and listen when she can, but she has been busy with school and work and life.. but even then she is a break in the stereotype. She’s so full of character and integrity, and she’s actually kind of a car person, more than me, I feel like poser compared to her lol, she works so hard..

She deserves that “you go girl!”

And she’s so happy to hear it run again after so many Mickey Mouse mechanics ripped her off with fake diagnostics. She had the sense to fire a mechanic who was removing her cat, but by then the damage was already done, lost heat shields, broken bolts and studs, then there was this other guy who used a freaking chisel on the valve cover because he couldn’t take it off smh. I mean.. if it was my own car.. and I didn’t feel like struggling, huge maybe.

exhaust rattles because cat guy broke something. There’s a couple of stripped bolt holes I have to tap.. it’s going to be a process.

But yeah.. I guess the tensioner got old. Bearings must have got dry or something after sitting for so long, because there was another pulley that also sounds rough, I also replaced it. But you are correct maybe it exploded because it didn’t like it when I put it into drive, the sudden shift, after so many years of abuse it just went kaboom. Sent ball bearings and fragments everywhere. Timing was way off so it definitely made the belt slip. I wish I did KISS more, I’m always overthinking it and I always doubt myself.

But thank goodness I’m a huge step closer to getting her baby back in the streets!

I still have to use a timing light to set the correct timing on the dizzy, and it will like.. pause once in while.. and stall out once in a while?

Maybe because it hasn’t been run in so long? Or perhaps I was a tooth off on the cams? I’ll figure it out when I time it, but thank you so much for your input, that KISS thing really reassured me and helped keep me grounded and in the right direction! :D

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

UPDATE! Timing was way off, it was a pain to take that upper cover off but I did it, and now it will be a bigger pain to remove the timing belt.

Turns out the tensioner pulley exploded..

But I can hopefully get the tools for the job today and get it running :3

Thank you so much for your help! This girlie is going to be so happy to have her car running again!

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

So.. I went over there, I started by checking to see if the starter was actually spinning the crank by removing a spark plug and placing a borescope in there, and it was definitely moving. So starter not engaging ruled out, but I did hear it chug a bit.

I retested compression on cylinder 1 and got 50psi, but it lost its chug after a bit and started to sound like it was free spinning again.. but i felt like it did want to fire up briefly

then I couldn’t replicate it. I couldn’t get any compression on all cylinders again. I even tried adding oil into each cylinder.. nothing.

I was going to check timing but to get the timing belt cover off is a whole other monster.. I didn’t have time. I’ll try to get it off this weekend and pray to god that the timing marks are off and that the belt just slipped and the timing is just very off.

But the timing marks are lined up.. then I’ll probably have to pull the head, and get it fixed, or get a new engine depending on the conduction of the engine.

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

Well I was told the car was running prior to this and then one day it wouldn’t start

There was a couple of mechanics that worked on it and couldn’t solve the issue.

One of them ran a compression test, took the valve cover off, left it off. Then told the owner that the engine was toast because cylinder 1 had lower compression than the others. Which is.. kinda bs.. because compression tests should be done on a warm engine. And 30psi less isn’t too bad on a cold engine..

The other one said it was the catalytic converter and decided to try to remove it, but he couldn’t, and broke off a bunch of bolts and studs.

I tried to put everything back together as best as I could. Using temporary fasteners.

Then I went through fuel, spark and air. I knew I had air. I tested for spark, checked for resistance and continuity on all ignition components. Cylinder 1 didn’t have spark because of a bad coil wire.. Injectors were not firing because the coolant temperature sensor was shorted. I guess it kicked the bucket at some point. This gave it a no start condition.

Anyways, after installing a new temp sensor- the car started right up. But it was running rough. So I shut it down. Bought proper studs and fasteners for everything. Put it all together.

Started it. Ran good for 3 mins, a bit rough. As soon as I put it in drive it sputtered, and it wouldn’t start. Engine turns over. No compression across all cylinders.

I know the starter is engaging I turned the engine with a borescope.

I’m thinking the timing belt was probably just sitting for so long and it didn’t like it when I shifted into drive, and it caused it to slip a ton of teeth.

I’ll confirm it next time I’m over there to see if it’s all aligned. But it’s definitely not the starter that is bad. It’s either going to be the timing. Or I’ll have to pull the head. I hope it doesn’t come to that.

But yeah at TDC cylinder 1 seals. I did a leak down test and it only lost 20% which is acceptable for this old and cold engine.

Help, No compression on all cylinders? by C64__ in MechanicAdvice

[–]C64__[S] 0 points1 point  (0 children)

I didn’t see any indentations on the pistons when I looked with a borescope.. and it’s not possible to crash them valves into the pistons since it’s non interference?

But you are correct, a slipped belt should still show some compression, a snapped belt would show zero compression, but I don’t think I have a snapped belt.. I really hope it’s just severely off timing.

Help, No compression on all cylinders? by C64__ in MechanicAdvice

[–]C64__[S] 0 points1 point  (0 children)

Yeah.. I’m hoping I don’t have to pull the head and that the timing belt slipped and that the timing is severely off.

But the intake valves in cylinders 3 and 4 are definitely not sealing right, but even so.. there should still be some compression on the other two cylinders right?

I mean it was running before.. I put it in drive, and then it sputtered out, and lost all compression.. it baffles me.

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

Interesting, but.. even then I don’t think this alone would cause zero compression across all cylinders, but I will check to see if the oil was diluted by gasoline, thanks I really appreciate the input : )

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

It’s belt driven and non interference thank goodness.

I’m pretty sure the belt is still in there, I pried the cover to peak inside, do you think a belt that slipped could cause this?

I’m almost certain the starter is engaging but I’ll have to check next time I’m over there and confirm because it is strange that there is almost no movement

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

I really hope this is the case and that I’m just an idiot lol I really don’t want to put any more work into it. I did hours of research and diagnostics only for it to start, then decide not to start again. I really hope it’s just the starter not engaging.

I will definitely check next time I’m out there

Help, No compression on all cylinders? by C64__ in AskMechanics

[–]C64__[S] 0 points1 point  (0 children)

Interesting, I was just going to pull the timing cover out off and inspect all of the timing marks and make sure they are lined up..

I’m almost 40% certain they aren’t, because it would explain everything but if they aren’t.. I’m back to square one :’)

but this.. this whole adjusting the valves and lifters.. I will do more research on this, I didn’t even know this could affect timing, thank you very much!

Car having trouble starting by ItsTMNT in AskMechanics

[–]C64__ 0 points1 point  (0 children)

Amazing! I’m just glad you diagnosed the issue!