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-   -   Serious but random problem (https://www.miataturbo.net/megasquirt-18/serious-but-random-problem-41379/)

evank 11-22-2009 12:31 AM

Serious but random problem
 
Right now I'm incredibly frustrated with my car. There's an intermittent problem where it runs fine, then it runs incredibly bad.

When it goes bad, it happens suddenly, not gradually. The engine gets extremely rough, misfires galore, and the CEL blinks -- scary stuff!!!

When I had similar problems a year ago, it was a bad injector. But that time it wasn't intermittent -- it was constant.

Now, the car runs fine sometimes, and terrible other times. There's not even any warning that the problem is about to happen. It just happens. Sometimes it goes away just as quickly.

I assumed this was a symptom of my botched coil pack wiring. So, today I very carefully and very methodically re-wired the coil packs. Then I drove 45 minutes without and problems. I was so encouraged that tonight I decided to go datalog .... son of a bitch problem came back!!!!

Here's my datalog. It is quite obvious when/where the problem starts.
http://snarc.net/datalog200911220014.xls

What should I do??? I do not have another car to use so I'm really fucked until I can fix this.

BTW, I listened to all four injectors with a long screwdriver, and they sound normal.

WonTon 11-22-2009 12:50 AM

if its not your injectors. may be a problem with you ignition system, plug wires, coils, sparkplugs, ect ect! a good place to start trouble shooting!

evank 11-22-2009 12:55 AM

The CEL is usually for random/multiple misfires, or misfires on cylinders 1/4. I have an extra coil pack so I swapped it for the 1/4 pack (2004 shares them.) No change -- problem still comes and goes.

But, I also had a non-blinking CEL for the same codes long before this new problem started. So it's very strange -- I have a blinking CEL when the problem happens, but there's no new code when I read them. WTF ?????

Meanwhile I ordered the Boundary/WeaponX COPS recently. They're supposedly shipping on Monday, which means they won't be here until Wednesday or Thursday at the soonest. And no offense meant to Boundary, but they're promised me once or twice already of shipping dates for this product that were missed.

WonTon 11-22-2009 01:06 AM

damn that sucks! i know there is a huge difference between honda and mazda. but a friend of mine had the same problem you were having and we couldn't figure it out for the longest time. turned out that one of his plug wire tubes was cracked and was grounding out somewhere causing his misfires and hesitations!

y8s 11-22-2009 07:10 PM

pro tip: post a screen capture of the megalogviewer graph instead of the excel file... i'm too lazy to download some file and open it and analyze it myself.

could be a power or ground problem.


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