h100vw 0 Posted November 28, 2003 All guess work-> That Vac pipe needs to be a metre long because it is a 'tuned length'. The pulses in the inlet manifold take time to make their way up the pipe to the MAP sensor in the ECU. If the pipe is shortened, the pulses get to the sensor quicker and confuse the ECU.(Cannot think of a better laymans explanation). It then cannot find and use, the correct fueling and timing requirements. You can shorten the pipe by a couple of cm and probably not create a problem. When you get to 5+cm short, thats when the poor running starts. Like Henny says it is cheap cheap and would be the first thing I'd check on any 10 year old G60. You can do the timimg easily but you need a timing light. If you don't know what one is, I'd recommend that you get it checked by a garage. Cheers Gavin Quote Share this post Link to post Share on other sites
