Wont rev at WOT

Engines, Transmissions & Final Drive questions and answers

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hks_kansei
Speed Racer
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Vehicle: NB8A
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Re: Wont rev at WOT

Postby hks_kansei » Fri Nov 25, 2016 2:54 pm

manga_blue wrote:(in NAs this means depressing the brake pedal just after disconnectng the battery, not sure about NBs)


Same for NB
Basically all you're doing is turning on some kind of electrical device (brake lights) to make sure the system isn't holding some small residual power.

Anything should work though, interior light, parkers, etc.
Brakes are just convenient since the brake lights are wired direct rather than through the ignition switch.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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jdm_wannabe
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Re: Wont rev at WOT

Postby jdm_wannabe » Fri Nov 25, 2016 5:06 pm

ManiacLachy wrote:OP, if it happens again find out what code is being thrown and investigate.

Will do., but hopefully it doesn't happen again.

manga_blue wrote:Maybe it's worth checking the ECU for moisture or corrosion?

Ok, I'll check it and if corroded I'll drench that bastard with circuit cleaner.

I see, but I didn't apply the brakes or any other electrical source, so the system still would've had residual power in it, strange.
So does this mean that the issue is only electrical, or could it still be mechanical?
Silver NB8B w/ matching hardtop. Want to turn it into a track monster :twisted:

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hks_kansei
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Re: Wont rev at WOT

Postby hks_kansei » Fri Nov 25, 2016 5:20 pm

jdm_wannabe wrote:
I see, but I didn't apply the brakes or any other electrical source, so the system still would've had residual power in it, strange.
So does this mean that the issue is only electrical, or could it still be mechanical?


It was probably fine, the system will lose power over time anyway, the brakes etc just speed it up.
If you left it for a while once unplugged it should be fine.



As for mechanical or electrical, still not really narrowed down.
It could have been a minor mechanical fault that caused the ecu to act weird, or the edu may have just done it itself.

Keep driving it, and if it comes back start hunting again.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

project.r.racing
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Re: Wont rev at WOT

Postby project.r.racing » Fri Nov 25, 2016 6:48 pm

spark leakage from the shaft between the spark plug and the coil. probably got a pin hole in it. should only happen under heavy load like you have described.

pull the coil out and lay the shaft across the engine head cover. if spark comes out anywhere other than the end of the shaft, you have found your issue.


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