Knocking? HELPPPPP!

[cixelsid]

Okay... I've read ninety ga-jillion posts tonight, hoping someone else had a similar problem and I could diagnose it from responses to another thread.... but alas, here I am - at the mercy of you fine fellows.


Just recently bought my 92 GSX - It WAS running great... for about a month or so
But now, the stinkin thing keeeeeeps BOGGGGING
I logged the last trip I made and it seems like the Knock Ret hits 15 whenever (or AND) my timing drops... If I stomp the gas for a moment - let it hit full boost & then let off quickly, when I ease back onto the accelerator it stops for a while. WTF?
Im wondering if perhaps I have a bad sensor or two? My A/F ratio NEVER used to get as rich as I've seen it recently. (It runs @ 14.6 when cruising and USUALLY only gets down to 13.1 or so when smashin the pedal - lately, it's been gettin down to 12.0!) Any ideas, comments or suggestions? I'm guessing from everyone elses posts that I should test for boost leaks first, right? I have always heard a whine and a whistle when the car is spooling up, it doesnt seem to have gotten any louder.

Here's a general overview of the car:

2.25" IC Piping (but not the IC )
K&N Cone
turboXS H34 racing bypass valve (Any Good?)
3" Turbo Back Exhaust
ShiftKit of some sort (it's an Auto )
AutoMeter EGT and Boost Gauge
Apex'i Pen style Turbo Timer
Some No Name A/F Ratio Gauge (like 7 or 8 LEDs lean to rich)
PalmN'Stein Datalogger (and palm of course)

-Is the Knock Ret display in PalmN'Stein the amount or instances of Knock?
-Is my car gonna DIE? Should I stop driving it till I diagnose it?
-Should I sell my soul to the devil for a nickel and a REAL turbo? (mine's a TD04)

Help a brotha out!!! Please!

 

[Quasimondo]

1. Unless you're using a true wideband o2 sensor/gauge, don't trust any of that blinking light crap. They all base their readings from the narrowband o2 sensor. The narrowband sensor has a voltage range of 0-1 volts. A wideband unit will have a range of 0-5 volts.

2. Does you get knock only at WOT, or does it happen at partial throttle as well? If it happens at partial throttle, then you're the victim of phantom knock, where various mechanical noises are picked up by the knock sensor and interpreted as spark knock.

3. How much boost are you running?

4. Are you still using the stock fuel pump?

If this is only occuring at WOT, I can think of a few scenarios:

1. You're running too much boost. If you're boosting more than 15 psi with the stock fuel setup, you'll get knock.

2. Your fuel pressure regulator is leaking and it's not raising fuel pressure under boost. To test that theory, get a set of vise grips and partially clamp the fuel return hose. That'll raise the fuel pressure, and if your knock count is reduced, then you need a new fuel pressure regulator.

Your car won't die, but you should ease up on the trottle until you get to the bottom of this problem. Your TDO4H is known as the 13G, which isn't a particularly large turbo, you could upgrade to a 14B (TDO5H) whis is the stock turbo for 5-speed dsm's, but track down your knock problems first.

 

[skinnyt]

wtf?what kind of knock low bangs or high pings.need more on that.

 

[cixelsid]

-Unless you're using a true wideband o2 sensor/gauge, don't trust any of that blinking light crap. They all base their readings from the narrowband o2 sensor......."

It's the OEM O2 sensor - Narrowband, but im getting the reading from the Apex'i TT and the data logged onto PalmN'Stein - Is that sufficient?

2. Do you get knock only at WOT, or does it happen at partial throttle as well? ......at partial throttle, then you're the victim of phantom knock, where various mechanical noises are picked up by the knock sensor and interpreted as spark knock.

It happens everywhere except when I let off the throttle. Could one of my valves tapping cause it to interpret spark knock? Lately, it sounds like I have a valve or lifter tapping rather loudly, of course, it increases in speed with the RPM's.

How much boost are you running?

My gauge says 10-11.5lbs - stock turbo with no MBC

Are you still using the stock fuel pump?

To the best of my knowledge, it has never been replaced.

Your fuel pressure regulator is leaking and it's not raising fuel pressure under boost. To test that theory, get.......

Thanks, I'll try that first thing tomorrow AM. Although... my O2 reading is ALL over the place and it tends to "Run Rich" (not only does that blinky light thing say so - it feels like iT)

wtf?what kind of knock low bangs or high pings.need more on that.

Whats the difference? I'm just going by what the datalogger is saying. the "Knock Ret" has a value between 0-15... It seems to climb up to 15 the further the accelerator is depressed.

 

[skinnyt]

my god it makes a big difference what the h*ll u thinkin man.a ping is good could be vavles.a bang or low nock is bad that means new motor.stop usin what ever your usin and use your ears man there more better than some palmpilot or dattalogger sounds like knock sensor anyway but damn use your ears forget that fancy crap you got.

 

[project94tsi]

carful boosting on a stock automatic fuel system they only have 390cc injectors compared to the 450cc that the manuals have, you say "not the intercooler" are you saying you dont have one or you just have a stock one, if you dont have one you would knock like crazy from the high intake temps.

 

[cixelsid]

my god it makes a big difference what the h*ll u thinkin man.a ping is good could be vavles.a bang or low nock is bad that means new motor.stop usin what ever your usin and use your ears man there more better than some palmpilot or dattalogger sounds like knock sensor anyway but damn use your ears forget that fancy crap you got.

Word. It sounds like I have a valve or lifter knocking, thats about it. Would the Knock Sensor picking up the valve tap cause it to run my car rich? If so, is there anyway to eliminate it without rebuilding my head?

 

[skinnyt]

hmmm back in the old days we used thicker oil like 20w-50 but u cant do that with turbo cars mine did the same thing but i rebuilt my motor.so i dont know what kind of oil you use so i recommend castrol syntic 10w-30.its about $30 for 5 qrts.how many miles on your car?

 

[skinnyt]

you know it could also be your oil filter better get oem oil filter

 

[cixelsid]

It does have an IC - the stock IC. The guy put the 2.25" upper IC piping on it, but left the IC stock.

I've been using the Penzoil 10w30 - can't afford the synthetic. Is there any other weight oil I can use to stop the tapping without adversely affecting the turbo?

Oh - it has 93k on the odo.

If I put a MBC on it - how much higher do you think I could boost with those 390cc injectors?

 

[Quasimondo]

if it is phantom knock then you're going to have to replace your lifters. In the meantime, you can use Lucas oil stabilizer, some have said that it works good. I've switched to using high mileage oil, which helped me out a bit. Of course there are those who will say that oil is oil and it won't help. Take it however you will.

The only thing that the knock sensor will do is affect your timing. I can't remember what the threshold is, but once your reach that limit, the ECU will pull your timing back one degree for every two additional counts above that threshold. Then after that, the BCS would kick in to cut your boost.

 

[cixelsid]

antom knock then you're going to have to replace your lifters. In the meantime, you can use Lucas oil stabilizer

Thanks man - I'll pick some of that up tomorrow.

The only thing that the knock sensor will do is affect your timing. I can't remember what the threshold is, but once your reach that limit, the ECU will pull your timing back one degree for every two additional counts above that threshold. Then after that, the BCS would kick in to cut your boost.

Can I reset the value by disconnx teh battery for a while?

 

[skinnyt]

93k isnt nothing.mine had 204000 when it started so u might whant to buy some new plugs i know sounds crazy but trust me.as for your oil it sounds good just might whant to change it just in case and oil filter.HOLD ON DO YOU HAVE AN INTERCOOLER ON THAT CAR?

 

[cixelsid]

....it just in case and oil filter.HOLD ON DO YOU HAVE AN INTERCOOLER ON THAT CAR?

Yes, yes, - it has the stock IC with 2.25" IC piping up top and stock piping on the bottom.

 

[cixelsid]

Hey guys, thanks for all your help

I changed my oil today and added some of that Lucas OT to it - I also used some Quaker State High Mileage oil. It sounded alot better at startup and ran a bit better. The tick is back though, albeit not as loud. It was pulling timing down to -3 with 15 counts of Knock Ret. Now, it seems to only pull it down to about 5. I guess i'll have to deal w it until I can afford a new set of lifters. Anyone have any suggestions as to where to obtain & what lifters to install/? 3g?