Trouble after MAFT install....

[brtmsx]

Okay, so I got done with my MAFT install yesterday and started tuning it using DSMLink. After just driving around for a bit and tuning it for highway cruising I decided it was time for some partial throttle runs, so I ease into the throttle and as soon as I hit about 50% throttle and get into boost the car starts bucking and my AFR goes crazy lean, which I assume is fuel cut, however I have mode 3 turned on my MAFT. Well after trying playing with the fuel and timing I decided it had to be fuel cut. And also on my way home I also noticed that my idle started surging from 850-1500 rpm. I have my idle set at 950 on DSMlink.

So with all of this taken into consideration the only thing I think could be wrong is a vac/boost leak. What do you guys think?

I dont know if it helps or not but heres a list of mods.
2g pistons, 1g rods, balance shaft removed, arp head studs/main studs and rod connecting bolts, crower titanium springs and retainers, revised lifters, comp 101300 cams, SBR g50 50-trim, DNP SS exhaust mani and O2 housing 38mm wg, DP back 3" thermal exhaust, SBR intake manifold, HKS bov, HKS turbo timer, SBR manual bc, FMIC, 720cc injectors, 255 pump, aeromotive FPR, maft, 3.5'' maf, aem eugo wideband

 

[bane3d]

+1 Boost leak test.

d

 

[architechnik]

What do you have the max rpm set at on DSMLink?

Honestly, it sounds like an incorrect reading from the MAF. Getting a boost leak would only show if that leak were between the engine and the MAF - manifold, throttle body, etc. The common stutter at idle is the ISC, although this should not effect the performance of the 50% throttle unless it is actually your pivot seals (I don't know if that's what they're called, but the seals that are along the pivot bar for your throttle plate).

The 50% mark is about where it swaps maps, though... entering into open loop operation. Could you have incorrect fuel maps loaded into it right now? What about dead time, pulse width, etc for those 720's?

 

[brtmsx]

What do you have the max rpm set at on DSMLink?

Honestly, it sounds like an incorrect reading from the MAF. Getting a boost leak would only show if that leak were between the engine and the MAF - manifold, throttle body, etc. The common stutter at idle is the ISC, although this should not effect the performance of the 50% throttle unless it is actually your pivot seals (I don't know if that's what they're called, but the seals that are along the pivot bar for your throttle plate).

The 50% mark is about where it swaps maps, though... entering into open loop operation. Could you have incorrect fuel maps loaded into it right now? What about dead time, pulse width, etc for those 720's?

Max rpm is set at 7250 I think. But no, I set the fuel/timing maps back to where they were when I still had my factory MAF after we had no results last night. I'll have to get back to you on the deadtime and all for the injectors.

 

[brtmsx]

okay so the deadtime is set to 405 and global adjustment at -38% with 44psi of fuel pressure.

after failing with dsmlink again tonight i tried just disconnecting my maf and the car ran fine. it was running rich as hell but even so i was able to go WOT with no problem whatsoever.

could it be my maf that is messed up?

another thing i couldnt figure out was when i was trying to tune the car my LTFT (lo and hi) and STFT wouldnt do anything whatsoever they both sat at 0.0 the entire time. so i had to tune off of my wideband. im having alot of trouble figuring all of this out

 

[Avionixx]

If your STFT or LTFTs aren't moving after driving for a bit, then your car isn't getting into closed loop. Either your ECT sensor is acting up or you're cooling your engine a little too efficiently.

 

[brtmsx]

Isnt there a way to force it into closed loop? and after the car is warmed up it runs at about 180 degrees.

 

[Avionixx]

I'm not sure if the coolant offset option works for the 1Gs, but other than that, there's no other way to force closed loop operation. You can force open loop though, so make sure you don't have that option enabled.

1G ECUs need to see 190F before it gets into closed loop operation, this is according to the DSMLink wiki.

 

[brtmsx]

okay, ill give it a shot. thanks!