If it's not the AFM,CAS, ECU or something related to the charging system, I'd check for things like a blocked exhaust system (e.g. blocked Cat or muffler) or blocked air filter. I had this annoying problem lately with my VY SS Commodore where the check engine symbol would come up on the dash. I know I damaged the left hand Cat when I hit a rock where Westrac were making me park my Commodore and that stuffed a brand new unit up, the muffler bloke only welded a standard 2.5 inch cat (I was in a hurry to get it fitted for rego) on the left hand side whereas I got them to weld a hi flow unit on the drivers side (I bought that myself over the net) , I'll get them to weld the same one on the passenger side. I did a bad thing (for the environment) by gutting the left hand cat out (I'm not working at the moment so I can't afford to buy a new one ) to isolate the fault because I was getting a lean reading from the left hand o2 sensor on my scan tool (0.1 volts, it fluctuates around 0.4 - 0.6 on average now, I think that's because there's less back pressure there now on the left hand side. The right hand o2 sensor failed to put out the right voltage (wasn't really working) so I fitted a spare one I had, that swings from 0.1 - 0.8 volts so I know that's working o.k. After I fitted that, the check engine symbol stopped coming up,it was amazing that because no fault codes were been set, they appear to be working because beforehand the ECU was stuck in open loop mode which was causing the check engine symbol to come up, when I fitted the other sensor, the ECU entered closed loop mode and started subtracting the both LTFT's & STFT's (short term & long term fuel trims) so I know that's working now. What has got me buggered is both the sensors are only 6 months old and I've had to replace one already.

Quote: Originally Posted by wkdvlt [View Post] Na dosnt get a chance to come onto boost, I might have to trailer it somewhere it's been at the auto elec for 3 days already . The strange thing is its only under load and moving its strange how old are the leads and what brand try another set of good leads the rb30 are very hard on leads which is 1 of the reasons for them blowing the cas up also what plugs are in it should have read further down

Quote: Originally Posted by RB30DEVL [View Post] If it's not the AFM,CAS, ECU or something related to the charging system, I'd check for things like a blocked exhaust system (e.g. blocked Cat or muffler) or blocked air filter. I had this annoying problem lately with my VY SS Commodore where the check engine symbol would come up on the dash. I know I damaged the left hand Cat when I hit a rock where Westrac were making me park my Commodore and that stuffed a brand new unit up, the muffler bloke only welded a standard 2.5 inch cat (I was in a hurry to get it fitted for rego) on the left hand side whereas I got them to weld a hi flow unit on the drivers side (I bought that myself over the net) , I'll get them to weld the same one on the passenger side. I did a bad thing (for the environment) by gutting the left hand cat out (I'm not working at the moment so I can't afford to buy a new one ) to isolate the fault because I was getting a lean reading from the left hand o2 sensor on my scan tool (0.1 volts, it fluctuates around 0.4 - 0.6 on average now, I think that's because there's less back pressure there now on the left hand side. The right hand o2 sensor failed to put out the right voltage (wasn't really working) so I fitted a spare one I had, that swings from 0.1 - 0.8 volts so I know that's working o.k. After I fitted that, the check engine symbol stopped coming up,it was amazing that because no fault codes were been set, they appear to be working because beforehand the ECU was stuck in open loop mode which was causing the check engine symbol to come up, when I fitted the other sensor, the ECU entered closed loop mode and started subtracting the both LTFT's & STFT's (short term & long term fuel trims) so I know that's working now. What has got me buggered is both the sensors are only 6 months old and I've had to replace one already. hahaha dude, your comments are always good for a laugh!