Engine misses and sputters in boost - Miata Turbo Forum - Boost cars, acquire cats.

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Old 02-01-2010, 11:20 AM   #1
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Default Engine misses and sputters in boost

When I hit boost, ill get some break up in the engine that I know isnt knock. ITs the ecu pulling timming most likely. I Set my knock threshold higher lastnight as I havent even played with it after I got the basemap from FM. It helped greatly but after I turned the car off, the problem comes back again. I did a hard save to the ecu and still the same problem. When I disconnect the TPS however, the issue goes away completely but then after restarting the car a few times its back. Im autotuning my Vac setting with the Nb02 which has yeilded me GREAT drivability in vac. Its set to tunr frmo 700-4500rpms.

Its not until the last 2 weeks that this started developing and its getting anoying as hell. I took a video scope of the pistons lastnight and there seems to be no detonation at all on the piston heads so thats a plus.

I havent gone into my voltage settings yet but I have a light feeling they are set to high as my immobilizer light for my alarm keeps flashing ever since i put the ecu in. This morning, I went to put the windows up and the raido cut out for the first time.

The other thing I need to look at is reducing my spark plug gap as of right now they are at 33. Gonna reduce em to 30. Im using NGK 6 heat range plugs.

If anyone has any input or has experienced this before, your help would be greatly appreciated.
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Old 02-01-2010, 12:42 PM   #2
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Stock coils? Reduce plug gap to 25...
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Old 02-02-2010, 10:22 AM   #3
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Yes, I think you need lower gap too.

Also, have you read FM's hydra tuning manual?

You need to set up your alternator settings. The radio will cut out when voltage is way too high or low. I don't know how much you're boosting but really, it's best to have stable current so you don't go lean when you have too little voltage.

The immobilizer will always flash. That's a "feature" that is just there for your enjoyment. No problems.
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Old 02-02-2010, 10:29 AM   #4
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I lowered the gap to 28 and everything is perfect now. Last night though I went into the alternator settings 2dpwm1 map. Only thing is, I saw nothing there that showed me actual voltage? My afrs are sitting perfect at 11.5-8
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Old 02-02-2010, 11:40 AM   #5
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Voltage is displayed on the main maps page. At least it used to be in 2.5
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Old 02-02-2010, 11:40 AM   #6
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Also download the hydra manual
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Old 02-02-2010, 11:45 AM   #7
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Did Hyper come over and fix it all for you?
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Old 02-02-2010, 11:57 AM   #8
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Quote:
Originally Posted by Splitime View Post
Did Hyper come over and fix it all for you?
lol...wonder how much that cost?
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Old 02-02-2010, 12:08 PM   #9
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You know the funny thing about Hyper is that he posted a genuinlly good write up on the fuel pump and voltage and converting everything to a return style setup. I couldnt refute much of what he had to say. Go figure the moron had the post removed.

Ill dl the manual now. I have to take a dump now
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Old 02-02-2010, 12:11 PM   #10
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I have it if you need it.
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