1G-GTEU rev problems?

[G0TR1C3?]

So my GX71 is still not playing nicely and now having a problem where after putting my foot down the revs will just completely drop to stall unless I constantly keep revving it

I have it set at 800rpm idle and just wondering if anyone here has had this problem before and would know what to look at?

So far I have been pointed to look at the idle speed control valve and recently saw someone with similar issue who was told to check AFM and possible dodgy O2 sensor? Are these also good points to look at?

If you haven't checked my build just replaced major electrics i.e. dizzy, leads, plugs, and drove home fine after that (apart from speedo cable snapping ) so those bases are covered. Just seems replace one part to have another fail atm which is starting to really shit me haha

Cheers for any help people

[king-szeitszam]

Had similar issues on my 2TGEU.
Could be about 50 different things. Things to check:

-ISCV is the first place to look, check your calibration and that it's operating correctly. Sometimes they get clogged up with shit and don't function correctly- although this generally leads to a fluctuating idle as opposed to what you're experiencing.
-AFM is another thing to look at as you've mentioned. O2 in my experience shouldn't have this impact as it's used as more of a fine tuning and calibration too to perfect the mixture- at least this is the case in my car.
-Check your FPR and make sure your pressures aren't fluctuating or rising- both at cold and hot- if it is you've most likely got a busted diaphragm.
-Another thing it could be is your TPS not calibrated correctly- i.e. there's a dead spot and when you press the peddle and throttle opens it doesn't register at the TPS correctly and the wrong input is sent to the ECU. Positioning of the TPS and the internal ECU settings in relation to it are both very important.
-Check your mapping and your A/F ratios at different throttle loads and RPM, could be an issue with how you've mapped it.
-Check your timing, especially if you've reset your ECU at some stage. It could be way off.
-If your cold start sensor is buggered then that will also explain your issues- try leaving the car to idle for 10 minutes and trying again. If it works hot then you've narrowed your problems down some more.
-Set the idle higher- when we did mine it was unstable at 800rpm so we started at 1500 and worked down until we reached the minimum stable idle.

Hope this helps.
Frank

[jondee86]

So my GX71 is still not playing nicely and now having a problem where after putting my foot down the revs will just completely drop to stall unless I constantly keep revving it

Checked fuel pressure and flow ??

Cheers... jondee86

[Z2TT]

Check TPS readings are in spec especially IDL circuit, then try another AFM, ....
Also Try running direct power to fuel pump aswell constantly to see if it changes anything.

[G0TR1C3?]

Cheers guys. Given me a few avenues to try hopefully will be sorted soon