Originally posted by pmckechnie
True, CIS systems are always spraying fuel when they are running, but it takes 40-50 psi of pressure to make them open and spray. It should only let fuel through if the pressure is above its opening pressure. A leaking injector will let the fuel go through intil the pressure gets to 0 psi. So yes they can leak and put too much fuel in the cylender.
If one reads this thread carefully, the problem is at idle, that is to say the enigine IS running thus the injectors are presurrized therefore cannot leak. per say, if a CIS is leaking enough at idle to have an impact, then drivability would result and a intermentant rough idle would be the least of ones worries, see this link for an understanding of the KE jetronic system www.volvoclub.org.uk/k_jectronic2.htm