took my car to the mechanic today, i had a bad o2 sensor and didn't feel like changing it.

so they fixed it, and said it was still throwing codes : bad knock sensor.

is this something i can fix, or do i need a new one?

 

Check the wiring first. If the wiring is ok, then you usually just replace sensor. IIRC, it's not a cheap sensor.

 

It Is Pretty Easy To Get To And The Very Slightly Mechanically Inclined Can Do This Job.

Mahjik, How Are You? Havent Spoken In Awhile You Probably Do Not Remember Me But You Have Helped Me In The Past, Thanks. Hopefully Tonight If All Goes Well My Fuel Issues That I Have Had For Over A Year May Be Over....

 

why do people use the J&S vs the stock one?

 

Of course I remember you. Good luck with your rework of your fuel system.

Some aftermarket ECUs like the PFC do not retard programming based on knock readings like the stock ECU. For those people who still want knock protection, they need an aftermarket unit.

 

so since i have the stock ecu, i'm better off with a stock knock sensor?

 

"Some aftermarket ECUs like the PFC do not retard programming based on knock readings like the stock ECU."






Yes......

 

Stocker Should Be Fine...

 

Yes STock Knock Sensor is best for stock comp and stock settings.

 

If I have a bad stock knock sensor but I am going PFC tomorrow, do I need to replace it?

Does the PFC even use the factory knock sensor?

 

It can display the output if you use a dataloger like the FC Datalogit, and it can warn you via the "knock threshold setting" by flashing the check engine light. Aside from the safety of knowing its values, the PFC doesn't actually USE the value to make any corrections to timing etc to save your motor. So in effect, no you don't HAVE to fix it, but you might want to.

 

Well I have a wideband O2 that is my primary warning, so if it goes lean I know...I suppose it would probably be wise to buy another knock sensor but at this point I am getting pretty low on funds so I would like to eliminate things that I don't "need."

So in my case I think it is pretty redundant...of course I could be wrong. If anyone thinks I need it, and that it could save an engine (while running the PFC) then please post.

 

wideband doesnt tell you if you're getting knock due to over advanced spark timing...

 

I guess I will find a new one then...

Anyone have one for sale?

 

it's very coomon to find that the knock sensor and power steering plugs have been swapped over. check this too

 

Whoa...those connectors are the same? I just got my car back yesterday, and I've had very odd knock readings from the PFC where it's basically directly correlated with the RPMs of the engine, and it almost sounds like the power steering swap could explain that! In other words, when the engine RPMs go up, the knock readings go up, regardless of load, gear, or anything.

Does this sound like it could be caused by this swap?

 

The PowerFC knock readings vary from one vehicle to another. At idle I always see about 5-6 on the knock meter, and if I cruise around or rev my engine to 3k RPMs with no boost, I get like 150 on the knock readout. I wouldn't trust the stock knock sensor for anything IMO.

I plan to buy a J&S unit when I have the extra $$ available.