Hi guys,

Yesterday I took out the car to put the first few miles on my fresh rebuilt engine. Everything looks fine except that the knock value seems pretty high compared to my old engine. I'm breaking the engine so I'm not reving higher than 4k and I don't go into boost and the reading is really high.

Normally I don't trust the knock sensor reading that much but I'm a bit concerned of what kind of value I will see when I'll beat the car.

Should I be worried?

I have replaced the stock engine mounts with Noltec, if that may matter.

Thanks

 

Do you have a Datalogit? Can you post a log?

 

Mine was the same way and my tuner told me that knock is only important under boost. When your not boosting all it is doing is picking up noises

 

I received a datalogit when I bought the car but I never used it.

 

Its just noise.

thewird

 

What a waste!

 

Do you want to donate it? heheheheh
it will be put to good use :P

now seriously, i have been trying to buy one...
but its not been easy so far

 

I never needed it until now and I have not paid for it. But I will get into it.

 

Have you experienced that kind of problem?

 

its the same **** with my car. i have knock at idle and cruise on an new rebuild, now i have 3500 km on the engine and started to introduce boost, like a 2-4 psi and the knock is going low when it boost, i'm also using the base map of brian cain. i just need a tune, but i have no money now since i'm at school in toronto for 7 more weeks

 

All the time. You have to keep in mind our sensors are 20 years old and parts on our cars are loose which could be causing false readings. Also, its a very simple sensor, it just picks up a frequency range and generates a voltage, modern knock sensors are more advanced. Some cars will read no knock, others will have random knock in vacuum areas, and even on occasion i've had sensors read some level of knock 100% of the time. On most cars though, usually knock stabilizes at WOT and full boost and then you can look at your average knock to see if its actually knocking. However, I don't rely on the knock sensor when tuning and neither should you. It is not a reliable point of data. You can have zero knock and easily blow a motor to hell.

Just and FYI, your not gonna hurt a motor in vacuum or at least, its very difficult. Just use the stock timing in vacuum, change it to zero split if you want and make sure the fueling is right and not studdering, you'll be fine. A nice lean cruise of 15-16 AFR and richening up approaching boost.

3,500 km? That's a lot of breakin mileage LOL, anymore then 1,000 is overkill. Your in Toronto? Dude, pass by, we'll go eat somewhere or something.

thewird

 

3,500 km? That's a lot of breakin mileage LOL, anymore then 1,000 is overkill. Your in Toronto? Dude, pass by, we'll go eat somewhere or something.

thewird[/QUOTE]

thats good to know bro. i didnt want to take a chance.lol. i'm in etobicoke right now, school its from monday to thursday. 730 am to about 2pm ( depends how the teacher feels) PM me your info and we'll meet up for sure

 

Thanks. Great info.

In my case I was concern because I didn't see knock that high with the old engine and I'm using the same PFC and the same knock sensor. I agree with you that it's hard to hurt the engine in vacuum and low load.