dthack03

iTrader: (6)

Recently the car has started idling rough and surging after its warmed up and when coming to a stop, occasionally will even stall out. Sometimes when setting back off if rpms remain below 2k will remain to surge slightly, but generally drives well after moving. Fresh maf and iacv, no apparent leaks or loose connections. No CEL, no problem starting, no hesitation. Was thinking maybe a less obvious vacuum leak or front o2? Thanks for any help or insight

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iTrader: (1)

What BOV do you have on your car?

dthack03

iTrader: (6)

Factory recirc (was thinking about getting a Cobb BPV), just went through and checked/tightened down all vacuum/boost connections I could get at. Cleaned up TB, then used CRC electrical contact cleaner to clean up some of the electrical connections, reattached IC-turbo and IC-TB. After this it appeared to help, but did not cure things (also didn't drive so no load after work, just start/idle/rev) Mainly when I turned the A/C on while idling (engine warm), idle dropped down as if the compressor pulled nearly all the power from the engine, then the engine caught itself and searched for a minute before settling back down to normal idle. A similar but much less intense event occurs when engine speed is raised and allowed to fall back to idle, no issue gaining rpm but when falling back to idle it dips down, searches, then finds idle. I'm starting to run out of ideas other than boost leak+comp test (don't have equipment for) and checking injectors/plugs/coilpacks/front o2 (a/f)? While engine idle drops if headlights are on they dim, I'm assuming this is from the engine speed/crank pulley slowing and thus alternator not creating as much e- current

Mods (tune related)- vf34, dw fuelpump and injectors, spearco IC, amr inlet, perrin short ram, tbe, protune. engine- mahle2.1 stroker pistons, sti crank-rods, king bearings (rod/main) and 03 wrx parts (head studs would have to double-check). Have bp numbers if relevant
Currently road tuned but do not have tactrix or windows to log, do have ap and extra ecu if it came to that (unfortunately do not have complete confidence in previous tuner, long story)

mistaanime

iTrader: (12)

Tried to clean the iavc yet?

I found that over the years. The iavc get clucked up and just removed it from the tb, took off the other sensors around it, sprayed wd 40 in it and cleaned it out until it was spinning freely. Doing this job will also have to replace the gasket between the iavc and the tb. Good luck.

dthack03

iTrader: (6)

Brand new iacv stated in first post, replaced gasket at same time.
Thank you