richman711 10 Posted June 26, 2015 Hi guys Was accelerating in the g60 hard this morning was at like 5k rpm in 4th when suddenly the car hiccuped and my boost dropped from about 14-psi to 10. I let off and drove sensibly for a few miles(car felt fine). Then opened her up again and in 3rd flooring it from 2.5k or felt normal but as soon as I hit 3.5k it goes flat, didn't rev it past that point. Any have any suggestions? Kyle Quote Share this post Link to post Share on other sites
Gti_Jamo 10 Posted June 26, 2015 Hi, Possible the belt slipping after a certain rpm. Weak tensioner maybe. Jamie Quote Share this post Link to post Share on other sites
richman711 10 Posted June 26, 2015 Cheers for the help Strangely on my way home it drove mine, pulled hard through the cars and hit 14 psi, so must be electrical. One thing I did think was that i was just below 1/4 tank of fuel going up a hill with my fitted down when it happened so maybe the fuel all slopped to the back of the tank? Quote Share this post Link to post Share on other sites
Album56 0 Posted June 28, 2015 (edited) Hi guys Was accelerating in the g60 hard this morning was at like 5k rpm in 4th when suddenly the car hiccuped and my boost dropped from about 14-psi to 10. I let off and drove sensibly for a few miles(car felt fine). Then opened her up again and in 3rd flooring it from 2.5k or felt normal but as soon as I hit 3.5k it goes flat, didn't rev it past that point. Any have any suggestions? Kyle What fuel are you using? Although the G60 runs on normal unleaded ok most of the time, it runs better on V power or other higher octane fuel, if there is any knocking/pinking the knock sensor will signal the ECU to dump boost via the ISV. Edited July 7, 2015 by Album56 Quote Share this post Link to post Share on other sites
JMC 0 Posted June 29, 2015 As Album says, it sounds like an ISV issue to me. Do you have a normal intercooler, and was it a hot day? Is the car running a standard chip or an aftermarket one? Also, as mentioned if you are not using V power, run the the fuel you have down (without flooring it) and only use V power. Normal fuel, high outside temps, and too much advance on the timing (could be a problem with an aftermarket chip) can lead to pinking and the ISV will vent and ECU with retard the timing leading to the symptoms you have. Try fresh good fuel, and a run in the cold weather (or middle of the night given the heat wave we are heading for) take it gently up in the revs and see what happens. Quote Share this post Link to post Share on other sites
Yandards 0 Posted June 29, 2015 Also go with a knock detection causing the ISV to dump all the boost back to return. If you could provide some more details of the car in terms of mods etc then it makes it easier to work out what is going on. Quote Share this post Link to post Share on other sites
richman711 10 Posted June 29, 2015 Cheers guys Heard about the isv bleeding boost, I normally run v-power but that tank full I think was actually BP ultimate (still gd fuel). Touch wood it's been fine since, so hopefully it was just the isv. Oh and it's running a standard intercooler but has been chipped Quote Share this post Link to post Share on other sites