C20LET Issue Help Please...

[*Adz*]

Right... Were to start....

I had a missfire.... Was really bad on idle.. seemed like was only kinda running on 2 cylinders as i put new plugs in...

1&2 come out black (sooty) 3&4 come out pretty much like new...

After changing the dizzy cap & rota arm for brand new ones, along with new NGK Cossie plugs gapped @ .6mm

Changing coil & MAF of my mates engine which are working fine on his engine...

I took one lead of at a time... and it changed note everytime... All leads are sparking as well...

Recently putting a new fuel pump in..... A Walbro GSS340 and Adjustable FPR which was previously on Paul Robinsons LET.... On standard yellow Injectors.

Sometimes it pulls like a train... then out of say every 5 times of pulling good.. it bogs down.. (no power) and then just back fires.. and its ok again...

Oh ive put a Ph2 ecu in there... but as far as im aware... it was working fine.

Also have no EML on either....

Im lead to belive from what ive changed etc.. that 3&4 injectors are naff? But i want some other opinions...

It was running ruff on idle but its sorted its self now.. and only does it under load.

Anything else you want to know.. Please ask....

Thanks in advance, id really like to get the car to PVS as well as ive spent so much money on it and wanna show it of!

[swedge]

have you tried swapping the injectors round then checking the plugs again?

[*Adz*]

have you tried swapping the injectors round then checking the plugs again?

Not yet... but the plugs are still like new at the moment... I have a set of saab reds here that i was going to put init.. but didnt want to do that and the adjustable fpr. Maybe just put them in it and see if it still does it then?

Ive got another ECU here im gonna stick init tomorrow... so i can see if its that or not.

[*Adz*]

Ive also done a compression test which come back @ 11,10,10,10 bar.

[Jeff16v]

Are all three earths around the fuel rail good or have you painted the inlet like me and forgot to clean the paint off where the earths mount.

[*Adz*]

Are all three earths around the fuel rail good or have you painted the inlet like me and forgot to clean the paint off where the earths mount.

Na inlet isnt painted mate... just normal colour... and yeh the earths are fine.. no frayed wires and all on the bolts correctly..

[Jeff16v]

Keith Robinson had a similar problem when he put his in the road, it turned out to be throttle position sensor, he ended up running bridging wires direct from the ecu to the switch as one of the wires had a break.

[*Adz*]

to be honest mate, i have no idea if its that.. im gonna put original fuel pump back on tomorrow and try that.. see what happens... then thats that problem written of as such... maybe try a different ecu if i get time inbetween jobs.

Thanks