Knock Question
- Thread starter rmorrell
- Start date
Does this happen at part throttle, or wot?
If at wot, i suppose it's possible the knock sensor is bad or possibly torqued too high.
If at part throttle, i'd be interested to hear from some of the more experienced members. I'm unsure as to whether the SM will display KR outside of wot.
If at wot, i suppose it's possible the knock sensor is bad or possibly torqued too high.
If at part throttle, i'd be interested to hear from some of the more experienced members. I'm unsure as to whether the SM will display KR outside of wot.
An overtightened knock sensor would be overly sensitive and be more likely to sense knock.
The knock sensor will report knock whenever it senses it,at any load or degree of throttle opening.
Have you checked to see if it's hooked up?
- Joined
- May 28, 2001
Torque is 14#/ft, no thread sealer, etc.
Sounds like it's working correctly.
If you think the engine is knocking and the knock sensor isn't picking it up,you should,at least,make sure fuel pressure is rising as it should.
If you have a high BL number and a low IAC number,at an idle,you should look for a vacuum leak.
If you think the engine is knocking,a vacuum leak is one of the things you should look for any way.
The motor is less likely to knock in first gear because there is less of a load on the motor. If it were knocking in first,it should get worse in second and third because of the greater load put on the motor.
Here are some numbers from the scanmaster at idle:
AF - 04
L8 - 26
INT - 128
BL - 142
IAC - 00
CC - always changing.
BL is higher so this means I must have a vacuum leak somewhere? What are common areas too look? Thanks.
Along with an IAC number of zero,it's a certainty.
Follow the vacuum lines from the throttle body vacuum block. There is also a gasket under the vacuum block. Throttle body gasket and upper and lower intake gaskets are possible but less likely sources..
The vacuum block gasket and TB gasket are newer, along with the rubber hoses coming off of the vacuum block. The hoses are tight. I doubt the metal lines are cracked but I suppose that could be a possibility. I will check that again. Could the intake hoses be a problem if they are not 100% tight? Im talking about the up pipe hose, the hose off the turbo and also the IC. I have the original style hose clamps and they are worn and stripped..Ttype6 said:
They would,most likely have to be ripped or disconnected to be a problem.
Any place that air can enter the motor after the MAF. Continue following the lines past the metal portion.
Been doing the carb cleaner test on problem areas and I cant find anything. The metal vacuum lines seem good. Turned boost down today to 11 and did test run. Same situation as I described before. Can hear ping coming out of turn going wot. No reading on SM. Other times I saw 1.6 deg pulled. Could fuel pressure possibly be an issue Instead of the vacuum leak. It seems like if my pump was dying then this same thing could happen..?
Eric Stage I
TurboTweak Guy
- Joined
- May 25, 2001
My chip is designed to ignore knock at very low speeds (around 25mph or less), because it is normally false. If you have the boost down to 11psi and you hear it knock, there is definitely a problem somewhere.
What do the O2's look like at WOT? If it's lean, could be a fuel system problem, or MAF problem, among others. Your high BLM at idle could also be a MAF problem, if you can't find any vac leaks and the PCV is ok.
Eric
What do the O2's look like at WOT? If it's lean, could be a fuel system problem, or MAF problem, among others. Your high BLM at idle could also be a MAF problem, if you can't find any vac leaks and the PCV is ok.
Eric
Eric Stage I said:
Tonight I recorded a 760mv but usually it seems closer to 800. I would say it's usually in that range, sometimes over 800. Should that mixture be more precise than that? Like say a number right on the dot every time? I checked for leaks around the PCV valve and it looked fine. The valve is new from RJC.
I also took a AF reading at WOT, and got 223 for a high. Not sure if there is any solid proof that the MAF is bad but it is stock and most likely the original MAF.
As far as false knock, the only thing that I can see causing that is sometimes my exhaust will rattle, I still have to perfect that. That pinging sound though is quite distinct, so Im sure I can tell the difference.
I am going to trouble shoot the fuel system as my next step after I get a good gauge and test the fuel pressure. Is the idling pressure supposed to be low 40s with an increase of 1 to 1 with each psi?
Thanks.
