My 3B to RS2 project

[Error404]

What injectors are you running mate?

[newsh]

EV14s with adapters, I wanted to leave the option of going back to the Dekas but ultimately I should probably change to the correct connectors..

Incidentally they were bought as a flow matched set and engraved as 750s but appear to actually be 850s

[newsh]

Worried about why I seem to be getting more knock on cylinder 4 than the others so did a compression test. All came in at 160 - 165 PSI (10.5 - 11 Bar) so doesn't seem to be any problems there..

[andy10v]

How do you know you are getting knock on cylinder 4?

All plugs the same condition?

You could ghetto test the injectors and see if 4 has poor spray pattern on flows less?

[newsh]

I've got some logging SW running on it.

I swapped the injectors out for the old Deka 630s and it still knocks on the same cylinder.

Cyl 4 is maybe 2 or 3 PSI higher on the compression test than the others.

All plugs look the same.

[newsh]

You could ghetto test the injectors and see if 4 has poor spray pattern on flows less?

Pull the fuel rail off and use 5 jam jars?

[andy10v]

Pull the fuel rail off and use 5 jam jars?

Yup, that is what I have done in the past, just looking for major spray pattern differences, and difference in volume.

Obviously not a very health a safety test

[andy10v]

I've got some logging SW running on it.

I swapped the injectors out for the old Deka 630s and it still knocks on the same cylinder.

Cyl 4 is maybe 2 or 3 PSI higher on the compression test than the others.

All plugs look the same.

Fancy

Same with different injectors would rule out injectors one would think, could also swap injectors cylinder to cylinder to confirm 100%.

What about signal to injectors? You replaced the connectors.

A hot point inside the cylinder would cause det?

I would not have thought 2-3psi would be significant? Unless you are right at the knock limit and that cylinder has slightly higher compression?

[newsh]

I think I'll try that tomorrow, I can see a bit of insulation cracking in the wiring to one or 2 injectors but not to Number 4!

This car has been doing my head in since the 5 coil - Pin swap Ish told me to leave it alone

[andy10v]

Swap the plugs cylinder to cylinder? Also coil packs?

Just basic elimination suggestions.

[andy10v]

This car has been doing my head in since the 5 coil - Pin swap Ish told me to leave it alone

You are not filling me with confidence

[newsh]

Swap the plugs cylinder to cylinder? Also coil packs?

Just basic elimination suggestions.

I've changed the plugs to new NGKs and back again to Bosche, no change.

Not tried coil packs

[andy10v]

Ebay £20 borescope?

Seems like a reasonable excuse to get one.

[newsh]

Ebay £20 borescope?

Seems like a reasonable excuse to get one.

Just ordered one of those tiny usb cameras, 6 quid

[andy10v]

A carbon deposit could increase compression and cause detonation.