System 2d fault. Constantly Injecting. Help please....

[ChrisMR2]

Hi all,
Newbie on here :D I have been using this system for a few years now and so far it has been excellent! Always run a 50/50 methanol/water mix. Anyways, over the last few days I have noticed my car knocking on cold start, fine when been running for a few minutes. I have noticed my system is constantly injecting! I can find no other fault with my car so presume it must be this causing the knock from cold. I used a gallon in a day :shock: Is this a boost switch fault? Is there a way of testing the componant? Are they available seperately?

Many Thanks in advance :D

Chris

[JohnA]

Why don't you disconnect the high pressure hose from the nozzle and see if it injects when it shouldn't (point it into a suitable container obviously)
If it starts injecting when the ignition power is on, then I guess the boost switch is knackered and you'd have to take off the pump fuse until it's changed for a good one.

[ChrisMR2]

It has an inline injector on it, and a small control unit to control it. It is constantly injecting at any engine speed with no boost. I have unplugged it, done a cold start and the knock has gone :D Just hope it has not damaged anything. Can I short the 2 wires to the boost pressure sensor to see if this stops it? Asking as when unplugged it still injects, and don't want to short them and damage the control unit.

Thanks,

Chris.