What causes a boost spike at 17% throttle and 1200 RPMs?
Thats not in between shifts or anything either (That wouldnt show up on the map sensor)
Is that ~1.7 bar boost at 1200rpm??? First off, where from and how are you logging boost??? A small displacement engine like yours does not put out enough exhaust flow at 1200rpm and 17% load to spool a 28xxR turbo to 1.7Bar(tuned normally of course). I mean that’s basically just off idle, and you sure as shit don’t have anti-lag tuned into that car…Boost log/reference doesn’t seem right to me…I know you don’t have an active boost gauge to verify that reading.
Unless you’ve got some major-fucked timing and a wastegate issue…Was that pulled from the Hondata???
I mean shit seriously…I wish I could build a proper setup for my car that pushed 1.7 bar at 1200rpms with nothng more than a tip into the throttle! :ponder You’re lucky to get most decent compressors onto their map at that rpm, let alone pushing 25lbs worth of airflow…
something fishy a-foot here
Its not spooling that, something is happening. Those numbers are coming right from the MAP sensor and I am logging all this stuff with my management program (not hondata but similar).
If you notice, the timing drops down to zero to be safe. I would think that this would be similar to the 2step type of thing where the fuel combusts in the turbo. The thing is though, it dropped down to zero due to the boost, so its a paradox.
Also notice I started at 7% throttle. The car bogged like a mother and I started kicking the gas to dig it out, thats when it went up to 21% and only 4 more RPMs
Personally, I think it’s time to just gut the entire wiring from that car and go a complete standalone with one off harness. It’s not OBDII so that’s nothing to worry about(MS and EDIS :errr ) You’ve been pulling your hair out with electrical issues from day one and it seems something else may be awry here.
If it’s not producing 25lbs of boost at the plenum, but your logging says it is…bad MAP or MAP wiring maybe :shrug: Unfortunately I’m not adept at all with Honda’s wiring and typical gremlins and don’t know much of where to look into a fix for such problems but to me it just seems highly likely as to be the culprit, especially with your cars fantastic electrical history.
The wiring is pretty simple and with the map its separate and easy for me to check it over. My program says its getting 4v at that spike so its not like its shorting. Possibly a bad sensor?
If I had my damn boost solenoid I would know for sure. :idiots
first thing i would do is set a boost cut so that the motor cant generate that much boost. this should allow for safer testing.
second i would test a different map sensor, 17 percent throttle, 1200rpm, 25psi is doubtfull. like adam said do you have a mechanical gauge to confirm that the motor is actually generating 25psi, not just the map sensor.
do you have a log saved you can email me?
I have a 15psi Boost cut on there. The thing is it wont do shit at 1200 RPMs and 17% throttle because thats lower than the back off point.
After thinking about it a little bit more, there is no way that its spooling at all there, it MUST be an issue with the map sensor. I would have heard the turbo spool if there was anything near that pressure.
Ill have to check the connections and then the map sensor again.
With the number of excellent plug and play managements for Honda why in the world would you do that? If the harness has issues just replace it with a good clean used one. Getting Megasquirt to work with VTEC and Hondas finicky VR sensors sounds like a gigantic headache to me.