I have about 6 months experience with HP Tuners, but have a good understanding of engines, computers and generally what to do here.. I have a L61 2.2 engine (2004 Cavalier) in a Miata that we road race. I have been working on the tune over the last 6 months, and got it pretty efficient, larger injectors, different air/exhaust/etc..
Anyway, just added a M62 supercharger, read though the fake bar threads, think I have implemented that, and got the engine running pretty well.
I have a wideband sensor into HPT, I know I have some work to do there on getting the fuel mixtures right, Once Im on the track I can do that, I find it?s impossible to do without real driving/dyno..
But I have some questions...
- How do I know if my spark timing is ok ?. What symptoms should I be looking for, what?s my goals with the timing advance @ different RPM ranges. Im using USA 91 Pump Gas.
- The IAT think?s it?s on Mars, reading 40-60c is this normal after rewiring it into a T-MAP after the supercharger - what should I expect here ?
- I don?t see anything on the knock sensor values, when does that actually kick in, if it's not registering, then I assume my spark's pretty good ?
I was able to take it about 500 ft down the alleyway tonight with Data logging, (Attached, with the tune), I never really got a chance for WOT
Any help or direction pointing is really appreciated, thank you !
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You definately want to fully finish fueling before ironing out spark. Fueling can cause knock to come on faster, more unexpectedly, and no system is there to reduce it. (like with knock sensors & spark) You should review the repository's supercharged tunes and for now just use timing simelar to what others are using with boosted applications, just remember you're using a "fake *BAR" tune and some of your table values have to be multiplied by 2, others by 0.5 or instead by whatever corosponding factor you've used to offset your injector & VE tables. That IAT sensor is actually an Air Charge Temperature sensor for the application on this car (and inside the GM parts catalog as well), and I don't think you can share it's circuit the way you're currently trying. That may be causing your funky readings, as well as preventing the PCM from beginning certain routines untill your temperature shows something normal. This may or may not affect Knock Learn/enable, Closed Loop enable, as well as others. I've also found the only way I can command any specific fueling AFR on theese cars with the available tables is in PE Mode while in Closed Loop and only after 1% Throttle Position. Any attempt to remove, disable, or disconnect sensors, as well as any sensor values being way too far out of range, or even the presence of certain DTC's will usually result in PCM not willing to enable Closed Loop. Because the o2 sensors have to be there, fuel trims will be playing with you the whole time. You can attempt to remedy this by using a wide band with simulated narrow band outputs, preventing the factory o2's from changing the trims, or you can use custom filters for your histograms that help to exclude the "bad" data. You should probably use at least one filter anyway, just for that spot below 1% TPS.
Dr. Nopps, thanks for the feedback, I will focus today on the fuel, it's getting pretty close, I may get some dyno time this week.
I have been going over the fake bar ecotec tunes, also the forum posts that are out there, that's how I got my first tune, then worked the fuel more.. im a tad ritch right now, but im ok with that, til I see the wideband while @ closed loop, I really don't know which way to go there.
Im looking for a data log from another one of these M62 on L61's so I can get an idea of their IAT values..
More to come as I discover & learn a little more !
I'm proudly a successfull stalker of an honor roll student!
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For that, simply go through the pages of this section untill you find posts from around 2007 or so and earlier. You will find a log from a 2.2 Ecotech build pretty easily, and it doesn't necessarily have to be a log from supercharged one. A user posted log of either style setup should generally include the PID for logging IAT which both would look within normal operating range, and nothing like the readings you're getting. Even though it is an Air Charge Temperature sensor, the PID for it is listed as IAT and you absolutely have to get those readings of yours figured out. Again it could be in the T-MAP way you're wiring it up, it could've gone bad, mabey even a short or ground issue just make sure you get that adressed.
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