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Discussion Starter #1
I'm really getting sick of fixing this car. I can't even complain about the car, because it's old, and sh*t happens.

Let's set the scene - new plug wires Wednesday. Took it out Thursday morning and it ran better than it has since I bought it 3 1/2 years ago. Everything was smooth. Perfect.

Driving home from school on Friday and we get into the second stop-and-go spot of traffic. Stop. Go. Stop. Go. You get it. Fine, normal. Start to go again, and the car shakes, VIOLENTLY halfway through first gear. It's hard to describe but I'll try. It feel like I had wheel-hop, except I wasn't going anywhere. It just shook real hard til about halfway through first gear. Every other gear was fine, every shift was alright.

I was still 5 hours from home at this point and 2 people in the car with me, so I figured I'd get it home as long as it cruised fine in 5th. Long ride, more traffic, more shaking.

I figured I may have snapped a bolt in a motor mount, judging by the symptoms. It pulled fine when the motor wasn't torqued over, and shook in first, when starting to accelerate. Ok so yesterday I jack the car up, unbolt all the mounts one by one, and they're fine.

Weird thing is, drove it around yesterday trying to duplicate it so my friend and I could try and figure out where the noise was coming from, but I couldn't. Seems like it just did it when the car was completely warmed up.

Also, since I've been home it's been doing the same stuff as before I filled my mounts. (Bouncy idle, idle dives when i hit the clutch to decelerate, clunky shifting)

I have no idea what is wrong, so if anyone's got ideas, I would be VERY appreciative.

Keep in mind - new plug wires. Nothing else has changed recently. And it happened out of nowhere. No gradual buildup. Car's fine, then it's not.

Could it be electrical? Plug wires? And it only happens in 1/2 a gear, with the rest fine, but the car is now running like crap.

PLEASE PLEASE PLEASE help me out here fellas.
 

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Did you check the usual suspect - TB boot? Just throwing it out there. Will definitely cause some bad shaking if there's a crack opening up when the engine moves in its mounts (i.e. starting from a stop).
 

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Discussion Starter #3
ah, good call. yea im goin out right now to reset the ecu (doubt that will do anything) and check a few more things. if there's a crack, wouldnt it cause problems other times as well?
 

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Discussion Starter #6 (Edited)
max said:
I would suggest double-checking the connection of your leads.
which ones?

MX-6Babe said:
What about the clutch plate? My boyfriends car did that and he found out it was a bad clutch plate. Only did it in first.
i was hoping not to hear something like that. clutch is <10k miles old, and was broken in properly (suppose it could be defective...?)

what's stumping me is that it did it out of nowhere, which would lead me to believe that something broke, or changed


problem is, i'm at home so the most im driving is 15-20min here and there, so i havent been able to duplicate it yet. as painful as it sounds and feels when it happens, i kinda wish it would do it again so i could try and diagnose it. im sure it'll return after 2 hours on the highway when i get stuck in traffic and then i'll really be screwed.

magik - TB boot is fine. i checked for leaks/cracks in all my hoses and what-not. honestly, do the boots crack that often that it's like the first answer to any kind of question about your car running like crap? i mean i knew someone was gonna suggest that, and i hear it all the time.
 

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i guess you doublechecked fireing at all 4 plugs.


once i replaced my plug wires and their boots.
the next day i got a miss, obvious one wire had come off. sure enough, on checking a new boot had slipped off causing the misfire. new boots sometimes have silicon on them and slip off.

i try to avoid confronting a new problem until i have eliminated causing that problem from my most recent work-if that is clear.
 

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dweigand said:
honestly, do the boots crack that often that it's like the first answer to any kind of question about your car running like crap? .
One word: YES. All TB boots need to be replaced at this age. If they are original they are likely dry-rotted and ready to crack at any moment. It sounds like that may not be the problem in your case though..was worth checknig anyhow.

At this point I would agree with others to double-check your plug wires ("leads").
 

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Discussion Starter #10 (Edited)
yea thats the first thing i did was check the wires b/c its the most recent thing i did to the car (gotcha jamin! good call...)

hotassgt - you may be right. overheated b/c it was ridin at 80ish for 2 hours by the point, and then sittin in traffic stop go stop go would probably do that. also, since the mounts were filled, i really cant slip the clutch that much as you gotta have pretty precise pedal-play to make the car go, otherwise it shakes b/c of the mounts. (if that makes sense)

i wasnt "riding" the clutch, but it may have just been slipping (clutch chatter?) b/c it was hot and overworked at the time. weird thing is, its pretty new (as i said) and it didnt do it in the summer or anything when it was much warmer in the first place (although i suppose the trans./clutch gets just as hot in the winter anyway)

well i reset the ecu and replugged all the wires, so i guess i wont know if that fixed anything until i'm on the highway in traffic again...baaahhh

if it is in fact "clutch chatter" is the only way to fix that to replace it? what a bummer...


"• Chattering and Grabbing — If the clutch chatters or grabs instead of engaging smoothly, the most likely cause is oil or grease on the clutch linings. A leaky crankshaft rear main oil seal may be the source of the unwanted oil. There could also be a leaky transmission or transaxle input shaft seal, a manifold or valve cover oil leak on the engine, binding in the clutch linkage or a broken powertrain mount. Other causes of this condition include binding or rust on the input shaft splines, broken or damaged clutch facings or pressure plate assembly, a warped clutch disc, damaged or broken damper springs in the clutch disc hub, or a collapsed marcel spring in the clutch disc"

Any way to check for a leak without unbolting the trans.? How would an input shaft seal leak or valve cover leak cause this?

This article also attributed grinding gears and sloppy shifting to "insufficient linkage travel" in the clutch linkage. How do I adjust the clutch on this car?
 

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no way to adjust linkage, since we have a hydraulic clutch. insufficient linkage travel would be the same as the clutch slave cylinder piston not travelling far enough to disengage the clutch disc. input shaft seal, is just that. the input shaft that drives the gears in the transmission, same area as rear main seals...just on the transmission side. as for the valve cover, this would be in the case is there was an actual clutch assembly (cable, linkage, etc).

but more than likely, it's the chatter caused by heat. that can happen on clutches just from being in stop and go traffic.
 

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Discussion Starter #12
so you think it may just be a fluke even? so maybe if i wasnt continually stopping and going i might be alright? b/c back and forth to school i hit a lot of accidents (retarded college kids mostly) and this is kinda an unavoidable situation. i would think clutches should be made to handle this kind of treatment...
 

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sometimes they can get a little cranky...i haven't had it happen yet with my 6...but with Z car, all the damn time. the clutch was fine, it just got hot from the stop and go traffic and city driving that seattle is so famous for. it can happen more if you have a clutch that's more performance orientated than OEM replacement.
 

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dweigand said:
How do I adjust the clutch on this car?
Under the dash loosen the jam nut on the clutch's push rod. Then turn the pushrod clockwise. Tighten jam nut. This will affect your clutch to engage earlier when releasing.
 

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bad advice

HotAss6GT said:
no way to adjust linkage, since we have a hydraulic clutch.
Wrong.

Absolutely, unequivocally wrong.
 

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SleepCounter said:
Wrong.

Absolutely, unequivocally wrong.
how so? he's asking for linkage...and in a hydraulic system...there is NO LINKAGE, only a pushrod. only in cable systems is linkage needed.

only adjustments would be to the clutch pedal assembly to change the engagement height of pedal just like max suggested above....but whatever, you may think of the pedal assembly as linkage.
 

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Discussion Starter #17
max said:
Under the dash loosen the jam nut on the clutch's push rod. Then turn the pushrod clockwise. Tighten jam nut. This will affect your clutch to engage earlier when releasing.
sweet well when its not 33.5 degrees and raining (so when it stops raining) i will try and play with that. i'm assuming its a good idea to note the original location of the push rod somehow incase i dont like the results.

how much turning is needed for it to make a difference? like a 1/2 turn will yield like a "sh*t i cant even drive my car now!" or what. i mean i'll trial and error it, but itd be nice to know beforehand.

hotass - sorry thats just what it mentioned on that website so it was stuck in my mind. i guess i was asking anywhere between my foot and the throwout bearing as the "linkage" b/c i knew there was a way
 

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werd up D...no worries :) I believe the pushrod is threaded, so it would be how much you unthread the pushrod, is how much sooner you want the clutch disengaged, i would say a good 2, maybe three turns? I'm not sure how it's threaded (i'm thinking a fine thread). If the thread isn't fine, maybe one turn will do. Maybe I'll shut up now, because I've never done it before nor had to...so yeah, I'll do that...:lol:
 

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facile/fog

HotAss6GT said:
there is NO LINKAGE, only a pushrod.
An adjustable pushrod.

tr said:
only adjustments would be to the clutch pedal assembly to change the engagement height of pedal just like max suggested above....
Isn't that what dweigand wanted? You know, when he asked "How do I adjust the clutch on this car?".

tr said:
but whatever, you may think of the pedal assembly as linkage.
Nope, I think of the clevis and pushrod as linkage. The pedal is a lever.

They link the pedal to the master cylinder. And they are adjustable.

Nice "thick" attempt to dodge, though.

tr said:
I believe the pushrod is threaded,
The end that threads into the clevis is threaded. It also has a jam nut.

tr said:
Maybe I'll shut up now, because I've never done it before nor had to...so yeah, I'll do that...
One wonders how you could state so unequivocally "no way to adjust linkage" in light of your lack of experience.

dweigand said:
How do I adjust the clutch on this car?
In the manner outlined above by max. What you need to achieve is about 3/4" to 1" of "free pedal play".

That is, there's a stage in the pedal travel where it presents much greater resistance. For the first little bit, you are just moving a spring near the pedal pivot, but once the real resistance starts (moving the pressure plate spring fingers), the pedal will be nioticeably more resistent to pushing.

That point should be about an inch into the travel -- the book says ½", but mine is about 1½" (in order for the clutch to engage earlier for better reaction times).

If you do not have any free play, clutch will slip. If you have too much free play, clutch will drag, even with the pedal on the floor, making shifts difficult and killing synchros.
 
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