slpstream4

Ok, I'm losing my mind with this thing. I'm running a MSPNP on a 1.6L with a Greddy turbo intercooled @ 8psi and an Innovate LC-1. I had it tuned pretty well, but recently added a BOV, and GM IAT sensor and reflashed the MSPNP firmware (thanks to brain's assistance) for the calibration. I tracked down a fuel pump relay transistor that was blown and replaced it, and removed the hated AFM.

So, after a few days of tweaking the idle and fuel maps, it's running pretty well. I have been using VE autotune to get the maps dialed in, but when I go WOT, and it reaches +5psi the car starts to lunge and hiccup. It's as if the fuel has been cut momentarily. Sometimes, depending on the rpm range, it will make it "through" the hiccup area and continue into boost. I replaced spark plugs, smoothed the map (fairly well?), and have checked out the BOV (thinking maybe it could be boost leak? - maybe it still is?). I'm at a loss. I feel pretty sure it's something simple, but it's making me wish I had left the AFM in and not re-tuned.

Please help!

slpstream4

added pic of megalogviewer and a tune file of the issue. The vertical line marks the start of the "hesitation"

messiahx

iTrader: (2)

Your fuel IS being cut completely. You can see the duty cycle drop to 0. What is your boost/MAP cutoff at? RPM limit?

Also, it would be more helpful to you and us if you put other variables on that MLV screenie other than MAP, AFR, and Duty Cycle 3 times. Add TP, RPM, etc.

slpstream4

Well, I updated the chart, and added my maps. I have no TPS, so I didn't put that on the chart. As for boost / MAP, are you referring to the VE map? It goes well above my 8psi levels. If not, you'll have to forgive my newness to MS. I added a shot of the RPM limits, but my max was only ~5500 on the chart. The hiccups seem to start as low as 3900 at 151kpa....


Well... as I type this, I find the "Over Boost Protection" menu.... was it really that easy all along???

messiahx

iTrader: (2)

Bingo! Don't feel too bad, I made plenty of silly mistakes learning. Killed a motor, too.

slpstream4

Thanks so much for the help!!! This forum is great.

slpstream4

So, I updated the Over Boost Protection to 170kpa last night. It was too late to take my loud car out after the update. I checked my oil, and noticed it was very low, so I added a quart or so, and installed another smaller air filter, so that I could get the air coming in from behind the headlight. Those were the ONLY changes I made last night. When I drove in to work this morning, I now barely make 5psi. What the heck? I was making 8psi (hence the 152kpa limit hit) all night long last night.

When I took the intake pipe off this evening, I noticed a slight amount of oil from the turbo, but found very little on the boost side. I'm stumped. Boost leak, maybe? But I can't find anything that's any different than it was last night.

Would the overboost protection change make it not make boost now? That would seem really odd, if so...

messiahx

iTrader: (2)

Changing overboost protection won't cause that. Something else has changed. I wouldn't be overly concerned with the oil, though if your turbo is ball bearing you will want to invest in a restrictor if you haven't already.

Start checking couplers. Are you running EBC? Easiest way to check for leaks is to let it idle and spray WD-40 or carb cleaner on all hose connections and it'll jump pretty quickly if any gets in.