3800 rpm haywire
#1
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Got the miata running again after being down for new everything. Got it out for its new tune and i have one of the problems i was suffering from ever since i turbo'd the car. it started up un noticeable and has gotton worse and worse. i am getting a big time sensor issue at 3800 rpm and only at this rpm. as long as i am out of boost or not getting on it hard i can go right thru the rev range fine, but when i am at 5 inches of merc or in any boost it bucks like a mother ******. after looking at the datalogs right at that rpm on my tuning pulls it shows huuuuge fluxuation in the coolant temp sensor going to straight cold to full hot wildly and same with my intake air temp sensor and now its moving into my map sensor showing some changes too. and my injector pulse width is going thru the roof too. its only at 3800 rpm under load. i am thinking something is throwing some rf but i am not sure, any ideas on this?
(shows up at the coolant temp sensor first, then the injectors, then the iat and then the map)
(shows up at the coolant temp sensor first, then the injectors, then the iat and then the map)
#15
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Full logs, and an MSQ, would be helpful.
So would an explanation of your TPS reading. Granted, the RPM and MAP look funky as hell, but the TPS just looks downright impossible.
So would an explanation of your TPS reading. Granted, the RPM and MAP look funky as hell, but the TPS just looks downright impossible.
#18
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The flutter in the RPM signal is what bothers me. Not sure if it's the cause or a symptom, but something ain't right about that. MAP and PW can go all to hell and back without violating any laws of physics, but RPM just can't do what the log says it's doing.
The timescale is just too damn wide in that screenshot to see any detail.
The timescale is just too damn wide in that screenshot to see any detail.