Stu.H

ok, 50% of the time, the car would only boost to .8bar , sometimes the full 1.7.

if i held it to the floor in 3rd, it would stop on .8bar, then after a few seconds holding it, it would shoot round to full boost. sorta like a loose connection.

checked wiring to amal valve, all oily, cleaned all up, still same

multimeter on connections, 12v on one wire when ignition on, also connected amal valve straight to the battery, clicks on and off fine.

so ...

I left the 12v feed on one of the pins for the amal valve, and connected the other straight to negative on battery. took out for a spin, and MINT, all sorted, straight to 1.7 in all gears.

My question is, is this how it should be, always 12v on one of the pins and the other pin always earthed? so its always on?

thanks in advance

TIFF

Sounds like a dodgey wire somewhere Stu

Stu.H

yep, but is it ok to leave it like this, or does the ECU need to talk to it? ie switch it on and off at certain times?

TIFF

I wouldnt leave it like it mate....Get it looked at or replace the wiring

Turbo Zetec

iTrader: (1)

i had this... ended up being a dodgy connection the amal valve, you could wiggle the terminal on the actual valve and it would move about making and losing a connection. tried another amal valve and it had exactly the same problem, i got fed up in the end and fitted a blitz dual SBC!

davidreader5

HI,

check the wiring to the amal valve for continuity,
the valve is a safety device as well as bleeding air off to raise the boost
level, it can close to drop boost depending on operating conditions of the
engine air temp etc, so makes life easier on the engine.unlike a manual
bleed valve.

Dave R.

Rick

amal valves are unreliable. I always bin them and use a bleed valve. Better boost response, no reilability issues.

Stu.H

when people put a 2 stage boost switch on dash, that goes to the ecu, is it the live or the earth thats used?

Rick

u just put a live and earth across the amal valve, with an inline switch.

Stu.H

not what im getting at, i need to know what the pin on the ecu is that people put the switch on when its done properly.

if its the live for the amal valve then fine, i can just rewire the earth pin to the chassis, if its the earth then I need to pull apart the loom a bit more.

Jim Galbally

Rick

done properly? what u trying to do? The amal valve is normally open (a lot of chips dont ever disable it). It takes 12V from the fuel pump relay, and earths to the ecu. The ecu can cut this earth if it needs, but there is no need for it to.

Stu.H

hmmm

Rick

Jim, thats not how an RST item works - i assume thats what Stu means.

Jim Galbally

you know what rick, i was just looking at that and thinking "i'm sure thats not for an RST"

its just a random pic from my photobucket account.

anyway, just run a 2 way switch instead, JOB DONE

Stu.H

I dont want to run a switch, I took mine out because I had it setup for high boost, thus would massively overfuel at low boost.

I want to know:

1) Does the ECU need to control the power to the amal valve?

2) Is the amal valve permanently live + earthed, ie on all the time

3) Is the pin on the ecu that gets switched to a live or an earth


Cheers

Rick

1 - it doesn't, no.
2 - That does't make sense - if it was permanently live and earthed, then it would be open all the time.
3 - The pin on the ecu is normally earthed, but the ecu can break the circuit to earth, causing the amal valve to close.

Jim Galbally

massively overfuel on low boost?

erm, its not supposed to do that, thats what the metering head is for

Stu.H

so your answers to questions 1 and 3 totally contradict each other.

Jim Galbally

no they don't

1) the ECU does not NEED to control the amal at all.
2) i know what you mean, and the answer is yes, its either on or off, it desnt pulse
3)earth

Rick

The ecu doesn't need to control power - it does so indirectly via the fuel pump relay - ie when the fuel pump is running, the amal valve has power.

The ECU can BREAK the route to earth, which will close the valve.

Rick

u can try putting a 12v feed to the terminal that normally has the black wire going to it. the green/red wire goes to the ecu. If u earth that to chassis, u will be on high boost all the time.

vroooom ptssssh

If my anal valve/wiring/power to it buggered up, could this cause my car to boost to 12psi?