spark knock

[Nismo20]

I have a s14 sr20det blacktop and i am getting a spark knock once the turbo starts boosting. and i pulled the plugs out and 2 and 3 are running real lean but 1 and 4 are are normal. What should i check to try and fix the problem?

[IanS]

by spark knock do you mean detonation? If it is detonation you are hearing you need to stop driving now, you are experiancing lean conditions that can lead to holes in pistons and all sorts of really bad stuff you dont want.

To really help diagnose the issue we are going to know a little bit more about your setup, what bolt ons are you running, what sort of engine managment, also what spark plugs, and things of that like.

[Nismo20]

Well i am have a FMIC, boost controller, full exhaust, stock ecu, stock injectors, and im running NGK bkr7es-11 plugs. T-28 turbo. but only cylinders 2 and 3 are running lean, cylinders 1 and 4 are running fine though

[IanS]

how do you know they are running lean, what condition are the plugs in, and what are they gapped to.

when was the last time you tested compression?

It could be that 2 of your fuel injectors are clogged

How much boost are you running?

are you using a stock fuel pump?

for quicker back and forth Q&A you can talk to me on AIM at Dr Nenappes03

[Nismo20]

i did a OHM test on all of the injectors and they all read 11.5. So what should i check now?