bradgalbraith 218 Report post Posted September 7, 2020 Hi all, Need some input from those in the know when it comes to S50B32s. I've currently got an issue with the following symptoms which all happen sporadically: -Rough idle -High idle from cold at approx 3k rpm -Hesitation on partial throttle but revs clean when not under load. Also pulls hard at WOT. Also worth noting that the car idles sporadically at about 1500rpm when the car is in gear. I know that there's a gear position switch by the clutch line but not sure why its affecting the idle.. I've checked and replaced the following: -Checked ICV and cleaned with carb cleaner. Valve was moving freely. INPA confirms that the ICV is functioning as it should. -Checked vacuum lines and nothing appeared perished -Beisan system vanos rebuild by Kayne Barrie. -Replaced TPS -Replaced throttle cable I've had the car on @M3AN's diagnostic and also BM workshop and all was showing as ok. I've checked the plugs and they look ok but I'm thinking it's not a coil or plug issue anyway since it revs hard under WOT or free revving. Could it be a crank or cam sensor? Maybe I'll check the vanos solenoid wires again? Trying to be efficient in finding the issue without replacing every part one by one $$$. Thanks in advance Brad Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted September 8, 2020 How are the o2 sensors, do they read and test OK? Quote Share this post Link to post Share on other sites
bradgalbraith 218 Report post Posted September 8, 2020 15 hours ago, KwS said: How are the o2 sensors, do they read and test OK? I believe they're ok. Didn't throw a code when tested but could be worth looking into. Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted September 8, 2020 Yeah it was the most common culprit I came across when trying to sort the idle issue with my S50b30 (though mine didn't have o2 sensors). Be worth checking Quote Share this post Link to post Share on other sites
euroriffic 609 Report post Posted September 9, 2020 I’m also still chasing the issue with mine with the odd hiccup on idle and that weird miss/flat spot on WOT around 2-3k. I Need to do a vacuum leak test first, but the exhaust camshaft sensor, or knock sensors can cause issues without a fault being brought up. So that’s my next step to replace all knock, cam and crank sensors since O2, TPS and MAF have been tried. 1 Quote Share this post Link to post Share on other sites
Funkyflynz 151 Report post Posted June 1, 2021 Any update on how things are going mate? Quote Share this post Link to post Share on other sites
