Car suddenly running rough and stalling
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- dbrick
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Re: Car suddenly running rough and stalling
I defer to Tom on testing, he has all my stuff!! , and yes, we all use the same basic set up. BTW, did you notice if the tachometer start waving around just BEFORE it runs badly? Car I was discussing above did that, tack flopped up and down for a few seconds, then the stalling and missing started. If it happens again and you know somebody with an oscilloscope, it may point you in a direction. Lets hope for the cap.
It's odd, a properly running engine and a properly beating human heart have a very similar waveform on a scope.
It's odd, a properly running engine and a properly beating human heart have a very similar waveform on a scope.
Dave Brisco
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- Skyman
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Re: Car suddenly running rough and stalling
Yes, tach swing, just as it starts to go bad. Since I replaced the cap and rotor, things are good so far. I just don't think it will be that simple though.dbrick wrote:I defer to Tom on testing, he has all my stuff!! , and yes, we all use the same basic set up. BTW, did you notice if the tachometer start waving around just BEFORE it runs badly? Car I was discussing above did that, tack flopped up and down for a few seconds, then the stalling and missing started. If it happens again and you know somebody with an oscilloscope, it may point you in a direction. Lets hope for the cap.
It's odd, a properly running engine and a properly beating human heart have a very similar waveform on a scope.
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- tjp
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Re: Car suddenly running rough and stalling
Although my issues were different, a new cap and rotor solved one of my rough running issues so it actually can be that simple. My other issue was a slightly broken wire coming off the coil that was totally un-noticable to the naked eye last summer on the way back from Mid-Ohio. It wasn't until the break was almost all the way through that we could actually see it.
Tim
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71 Jeep Gladiator. Restored w/#s matching engine. My WeeBeasty
70 1600 legit 2nd owner. Stroked and bored
Several salvaged w access to a barn full of parts, part cars & whole cars
......What's in the barn is for sale. What do you need?
- spl310
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Re: Car suddenly running rough and stalling
I suspect a loose wire somewhere. I would judiciously check all connections.
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- Linda
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Re: Car suddenly running rough and stalling
I had a bad connector on a MSD wire recently, it broke. So check all that too.
Linda
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- Skyman
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Re: Car suddenly running rough and stalling
spl310 wrote:I suspect a loose wire somewhere. I would judiciously check all connections.
I have checked the resistance of every wire from the coil to the distributor. If it were prior to that, the tach would just drop along with the power. If, per se, it were coming from a bad connection on the ignition switch or something then it would all just fail. It is the wild tach swings associated with the misfiring that tells me it is between the coil and distributor. I'll be more prepared to test if it occurs again. I really appreciate all the ideas.Linda wrote:I had a bad connector on a MSD wire recently, it broke. So check all that too.
Linda
I was kind of saying that in hopeful jest. I really do hope it is that simple. Thanks for your support.tputland wrote:Although my issues were different, a new cap and rotor solved one of my rough running issues so it actually can be that simple. My other issue was a slightly broken wire coming off the coil that was totally un-noticable to the naked eye last summer on the way back from Mid-Ohio. It wasn't until the break was almost all the way through that we could actually see it.
Tim
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- Skyman
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Re: Car suddenly running rough and stalling
Over 200 miles now, and no issues. Maybe it was just the cap & rotor?
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- notoptoy
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Re: Car suddenly running rough and stalling
I have seen a crack in the cap cause all sorts of weird running issues, especially if there is high humidity - it'll "rain" inside the cap.
My typical test for that is to simply watch the car run at night, as dark as you can get it, to see the arcing.
My typical test for that is to simply watch the car run at night, as dark as you can get it, to see the arcing.
"When all else fails, force prevails!" Ummm, we're gonna need a bigger hammer here.
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- dbrick
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Re: Car suddenly running rough and stalling
I agree, bad cap will make you crazy. BTW, did you see the cool wheels in SLC in the forum classifieds? http://www.311s.org/phpBB3/viewtopic.php?f=6&t=14467Skyman wrote:Over 200 miles now, and no issues. Maybe it was just the cap & rotor?
Dave Brisco
Take my advice, I'm not using it"
66 2000 The Bobster
64 1500 in pieces for sale
1980 Fiat X1/9
2009 Volvo C-70
08 Expedition EL, STUPID huge but comfy
1962 Thompson Sea Lancer, possible money pit
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Re: Car suddenly running rough and stalling
I put a new coil on mine. Same symptoms. The old ones get hot and stop working
- redroadster
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Re: Car suddenly running rough and stalling
How many miles now 12 yrs later ?
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Mitsubishi tech 9 yrs
Volvo, Kia, Toyota too
6 month - Rolls Royce
ASE MASTER TECH 96. - 11
70 SPL 86 Z31 T , Sportster