"wkiernan" (wkiernan)
01/05/2018 at 17:19 • Filed to: None
2
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"wkiernan" (wkiernan)
01/05/2018 at 17:19 • Filed to: None | 2
| 18 |
What you see above is a little bit of unvarnished flattery, because I need some car-oriented advice, and I’m sure the Oppo crowd is the world’s finest source for that (yet more flattery). To !!!error: Indecipherable SUB-paragraph formatting!!!
!!! UNKNOWN CONTENT TYPE !!!
I replied:
*****
My ‘04 Miata misfires horribly and won’t rev over 2000 RPM for the
first minute after I turn it on in any weather cooler than about 70° F.
This last week I’ve had to let it warm up for at least 120 seconds
before I try to take it down the driveway, and then it still misfires
some until the engine is all the way up to full heat.
It
never did anything like this until I took it to a mechanic to get the
timing belt changed. When I went to pick it up after the “repair” I
couldn’t even make it down the block. I took it back and they “fixed”
it some more so it was capable of starting and running, but only in warm
weather. What I’m saying is, it isn’t some part like bad coil packs
that has slowly, gradually become dysfunctional. No, this was a
pure-and-simple mechanic’s fuck-up, like the wire to a sensor wasn’t
connected right or some part got put in upside-down when they bolted
everything back on after changing the belt.
Let me ask you all
this. When a mechanic works on your car, wouldn’t you expect him to at
least check to see if it works at all? I’m not asking for uniformed
inspectors to flog it several miles at WOT around Weissbach looking for
barely-detectible vibrational anomalies, I’m asking for somebody to just
try to drive it around the block to make sure that when you pick it up
it will at least be able to make it down the road without bucking and
stalling. Is that too much to ask? Fuck fuck fuck.
This is bullshit, and friends told me I should take it back a third time and have the mechanic fix it properly, but I figured that if he fucked it up that bad I wasn’t about to let him ever lay a finger on it again.
Anybody got any suggestions? Anybody know a competent Miata mechanic in the Tampa Bay area? Fuck.
*****
Well that’s my problem, but I guess I should throw in a few more “fuck”s, so nobody will say “Oh that guy, he just doesn’t give a fuck.” Fuck. Fuck! Fuckity fuck.
Takuro Spirit
> wkiernan
01/05/2018 at 17:53 |
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No CEL? Almost sounds like a MAF issue, or a sensor that’s not reading right until going into closed loop mode.
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wkiernan
> Takuro Spirit
01/05/2018 at 18:12 |
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THANKS, going to pick up a can of MAF cleaner on the way home and give that a try.
crowmolly
> wkiernan
01/05/2018 at 18:14 |
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When did you have it worked on?
Not having worked on a Miata timing setup I can’t say for certain but it sure seems like he fucked up the timing belt installation outright. Somebody else needs to confirm, but if it’s possible to replace the belt/gears/etc a few teeth off I’d say that may be it.
Once it hits closed loop the engine can make adjustments to run better and again once it’s warm. But in open loop it’s ignoring sensors and will run poorly.
XJDano
> wkiernan
01/05/2018 at 18:17 |
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Yeah, I would expect them to test drive it. Not exactly 40-80 pulls on the highway or anything, but around the block.
Not necessarily for an oil change but for anything else or replacing parts.
Not sure on the weird start and warm up issue.
Die-Trying
> wkiernan
01/05/2018 at 18:20 |
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could be some sort of vacuum leak, or a sensor that got disconnected or bumped while trying to take off and put back all the parts that are covering the timing belt. all those hoses, and wires in that front area are where i would look at first...... might even be the intake tube is just shoved on there without being tightened, and letting in air...... it ought to be something fairly simple......
Ash78, voting early and often
> wkiernan
01/05/2018 at 18:23 |
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Well, the first fuckin problem was not fuckin bringing to Oppo directly.
I second the MAF suggestion.
First, unplug the MAF and see if the car runs crazy, but at least runs. Most cars will sense a missing MAF and revert to generic air/fuel ratios. If that’s the culprit, try some CRC MAF cleaner ($5 anywhere).
Worst case, get a new MAF for $50-$200. They’re almost plug & play, usually just a few screws.
Wrong Wheel Drive (41%)
> wkiernan
01/05/2018 at 18:37 |
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I have definitely seen this on miata.net as a proposed issue on an NB2 before, so it would do you much good to search there more thoroughly. I know I have read through threads about issues just like this. Most of the time Cam sensor ends up being the culprit! Or crank sensor. But anyways, you said this specifically came up after the timing belt change. My car is an ‘01 so its exactly the same motor 100%, I did the timing belt change myself so I kind of have an idea of what parts came on and off. There are VERY few things that could have been messed up on this car with that job. If its not misfiring ALL the time, I would seriously doubt timing was off. Aside from that it has to just be wiring issue, maybe something got buggered up pulling out a connector, something got crushed by a gorilla (mechanic), or spark plugs arent gapped right or something weird like that. You have to meticulously troubleshoot every part of the issue, forget the screwup mechanic. Cut your losses and learn the repair item yourself. Miatas are easy to work on so theres only so many things that could be wrong.
Cam sensor along with just about every other electrical sensor gets disconnected with this job. The VVT system gets removed from the cam, radiator comes out of the car, valve cover comes off, spark plugs come out (along with the coil on plugs and wires of course), and thats about it. Aside from the timing related components and waterpump of course.
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Wrong Wheel Drive (41%)
> crowmolly
01/05/2018 at 18:40 |
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If its off even a half of a tooth, it will run HORRIBLY immediately and forever. It wont just be a cold issue. Ask me how I know lol... I had to redo the entire job on my ‘01 Miata because of this problem...
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Wrong Wheel Drive (41%)
> Die-Trying
01/05/2018 at 18:42 |
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Also, vacuum hoses could have cracked or stretched just a little too much. Meaning they might not leak all of the time. And heating up could solve it. It sounds like an intermitten issue so if its not electrical, this would be my guess. There a few attached to the valve cover to look at. Along with a bunch on the passenger side of the engine (although those didnt need to come off for the job).
sony1492
> wkiernan
01/05/2018 at 18:52 |
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As others have said, turn the car off and unplug the maf. If the car runs the same or better that’s most likely your issue. I wouldn’t suggest maf cleaner, it’s been said that it can damage a maf and should be a last resort.
weasel the great (not actually all that great)
> wkiernan
01/05/2018 at 18:59 |
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It’s kind of hard to tell from the pic, but it looks like you may be missing a ground connection by your throttle body. The top right bolt under that vacuum elbow should be a 10mm with a ground strap and some wires coming off of it. I accidentally left that off when I replaced my intake gasket and it caused all kinds of weird behavior from the fuel injection system. I would post a picture of mine on my 2003, but I can never get pics to post here for whatever reason.
If that isn’t it, just go over all of your vacuum lines and sensor connectors to make sure one isn’t unplugged. They’re easy to miss, and it really sounds like that may be your problem. Good luck!
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Die-Trying
> Wrong Wheel Drive (41%)
01/05/2018 at 19:00 |
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and depending on how in a rush, or absent minded the guy was while putting it back together, might check the firing order to be certain. like crow said the outright belt instalation might of gotten muddled. found a picture after a quick bit of hunting....
the Es and Is on the pulleys need to line up with the metal plate behind them, and the tooth count between the timing marks on the topside is important too. link to picture....
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weasel the great (not actually all that great)
> XJDano
01/05/2018 at 19:01 |
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Mechanics do make mistakes from time to time, but not test driving it is pretty ridiculous. I’d be finding a new mechanic.
Kanaric
> wkiernan
01/05/2018 at 19:02 |
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I had this exact problem with a 89 Nissan Skyline which uses a MAF sensor. I thought it was the MAF the whole time, cleaned it and even went as far as to buy a new one, but it was the water temp sensor that was the problem. Once the car warmed up it ran well but if the water was at a low temperature it behaved like you say here.
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Wrong Wheel Drive (41%)
> Die-Trying
01/06/2018 at 00:30 |
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The BIG problem in that photo is that it isn’t of a car with VVT, meaning it is an ‘00 or older. His car has the VVT on the left (passenger side) cam so there are no marks to line up conveniently like this photo. You kind of have to look at it at a weird angle and it will look slightly off when it’s actually right. It was kinda tricky but if you get it wrong, the car will run but just barely. Same goes for firing order, there’s no way you are pulling out of the parking lot much less making it home. Also on this car it’s REALLY hard to mess up the firing order. The plug wires are each a specific length and you not be able to get all four in if you put on in the wrong place. I agree though that laziness by the mechanic is surely a factor here though.
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Wrong Wheel Drive (41%)
> weasel the great (not actually all that great)
01/06/2018 at 00:38 |
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I forgot about grounds! Yes this is very likely a cause of the problem. However, the issue only occurring when cold worries me with this prognosis. It could still be a factor with a faulty ground, just more likely a loose one than one not there at all. However, it’s certainly an easy one to cross off the list and try.
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Wrong Wheel Drive (41%)
> wkiernan
01/06/2018 at 00:41 |
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Also, I’m jealous of how clean your Miata engine bay is. Also that you have a non broken oil dipstick, both headlights have non broken mounting clips, and you’ve got the fancy smancy ABS
Rupert Palatipelen
> Takuro Spirit
09/29/2018 at 23:04 |
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had an 02 protege5 2.0 it did alot of the same with collapsed fuel strainer. ethanol caused it to rust something fierce.