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Discussion Starter #1
Hey guys, got an odd problem and seeing if anyone has ideas. I've got an 01 ZX3 that has recently developed a miss under acceleration, but only around 3-4k RPM. Only when warm, the problem isn't there when I first start the car. No noob light. I've swapped the coil, replaced wires & plugs with no improvement. Also I've changed the fuel filter just in case, but nothing. At this point I'm thinking it may be the crank sensor. I pulled it and, externally at least, it looks ok. I would normally think fuel since ignition has all been swapped but the interesting thing is, if I have enough power I can 'punch through' and once I get over that RPM range it runs fine again. It just sucks because I can't do it with a 350k motor in fifth gear, and it's pretty jarring/annoying accelerating with a stutter.

 

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Have you checked the coil harness? Well known for developing tiny cracks right at the plug where they're hard to see. Mine ran weird for a few weeks before ever throwing a code, and like yours it would only do it under load.
 

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What on earth are you doing at 4000 rpm and in 5th gear? Thinking you are speeding a bit there.
 

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What on earth are you doing at 4000 rpm and in 5th gear? Thinking you are speeding a bit there.
That wasn't fifth gear. You can clearly see the upshift indicator light at the bottom of the tach. lol
 

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Did not watch the link, only read the post, he clearly states it.

lol back atcha...............
 

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Discussion Starter #6
Thanks for the suggestion Leora, I'm planning to check into that as well. I mentioned fifth because I can't really get past it in fifth, but can in 3rd and 4th, and videoed that just to help show that it's not a fuel delivery problem in 3rd iirc. I just get to that speed in fifth (~85) when I'm cruising the interstate...in Mexico of course, but it irks me in other gears knowing that something isn't right
 

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The fact that you can get past it in any gear suggests it's likely not the coil harness, but it's an easy enough check and a known problem area on these cars.

Did you scan it for pending codes?
 

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Discussion Starter #8
Fixed. There were no pending codes, I swapped the crank sensor for a spare used one and it's not been stupid since, including the 7-hour trip to the OBX I took this week :)
 
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