HELP! False Knock!

[DR. EVIL]

My car is getting false knock in the top end, usually in the mid to top of 3rd and on.... I had a full tank of 99 octane in with a 93 octane setup and still getting the knock....

Wierd thing is that it goes up and down while I'm still in WOT. It will accelerate fine, then get knock, go up higher, back to 0 kr then back up again... you can feel it retarding and then adding back in timing all during the same WOT pedal press.

Could this be the knock sensor? ECM? Chip? I've also had some backfiring after startup on acceleration, it runs really rich for a while, and eventually starts running correctly. it will stay in the 700+ O2 level at idle, and then just kinda click back to normal outta nowhere.....

Are these signs of something specific. Could the IAC have anything to do with my problems? I haven't set it since I put the new one in.....

 

[Kevin Turch]

Are your motor mounts good?
Im having the same problem, except i get knock whenever it feels like knocking

 

[DR. EVIL]

I checked the other day, doesn't look like the engine moves anymore than it should when you rev it. However, my tie down is bent from the motor constantly pulling on it I'll have to fix it or replace it.

I did notice a small dent in the bottom of my THDP when I was under the car the other day....... I wonder how often that hits something....

 

[Kevin Turch]

I had to dent mine pretty good to get it not to hit, i should of not been lazy and just did the MM first, now i have to do them after banging my pipe afterall
Kevin

 

[Richard Inglett]

Try Bypassing Timing Feature

First let me state that I think the Translator Plus is a very clever device and other than me, you may be the only other person whose timing feature has died. In my case, car backfires and will not run correctly if the timing feature is connected. Bypass the timing feature and everything is OK.

You should have been supplied a female bypass plug. Try it and see what happens. If it is bad, you have an excuse to upgrade your Translator and possibly your chip.

Good luck

 

[Russ Merritt]

That doesn't sound like false knock. It happens at the top of third @ 100mphish. That sounds like real knock. I have the mother of all false koncks, as soon as I floor it, on the way up the rpm road it pulls 30-40 deg. With a 3 sec delay in the chip no knock @ 18+ #, 94 oct through out the pull all the way to 5500rpm,110mph. Thats with NOTHING hitting anything! Yours sounds like the car is settled down making power, then towards the end of the pull it starts its knock, REAL knock. What kind of boost press? Is this on the street or track? Timing in the chip? How much knock retard?

 

[Fred 86 GN]

It is probably REAL knock.

Mine does the same thing -- couple degrees in the top of third gear. It will go away then come back sometimes during the same run. Mine got worse when I turned the boost up another psi...so I believe mine is real. Mine was less than 3° most of the time.

You need to reduce the boost or increase the octane, assuming your O2 numbers are in the high 700s or low 800s at WOT in third gear. Some cars, like mine, seem to need more detonation resistance than others.

If is walks like a duck and quacks like a duck...

HTH

 

[Russ Merritt]

3 degrees is nothing to worry about, your all set. Running on the edge, life is good.

 

[DR. EVIL]

Russ Merritt:
What kind of boost press? 15-16psi
Is this on the street or track? Street
Timing in the chip? 19 deg
How much knock retard? 17+

This was with 99 octane It isn't doing it every time, and sometimes the boost will go up at the same time 2psi... for instance today.. it was running good at WOT staying at 16psi, then it jumps to 18psi out of nowhere and starts knocking too. I used to run 18psi all the time with no knock, until I this BS started happening, I can even go partial throttle sometimes and at 10psi it will get KR and the boost will jump to 12psi out of no where..... that boost thing might be a unrelated occurance though.

Most of the time though, it will knock regardless of what the boost does....

Richard Inglett:
If I bypass the timing feature, I'll have to either throw my old Red Armstrong chip in, or put 99 octane in becuase it's a 98 octane chip that I turn the timing down on the Translator for.
I did try out the old chip, set the timing on the translator to no change and it still did the false knock thing.... could the Translator still be messing with the timing even with a different chip in?

 

[Russ Merritt]

Let me ask a stupid question, What do you have holding the wastegate actuator to the swing valve? I had a similar problem with my car last year, turned out to be the ATR DP swing valve binding up! Sometimes the "alligator" clips don't allow smooth operation of the wastegate, hence your problem. I am using the clip from the throttle linkage on my actuator/swing valve (junkyard) works pissa.

 

[DR. EVIL]

I have the stock clip on the wastegate....

I have a .63 Precision exhaust housing on the TA-51, I'm not sure if it's drilled out large enough for the puck, anyone know? Could that be a reason? Could the Wastegate just be bad?

I have a Manual ball/spring type boost controller, so I know it's not going to make the boost change during WOT, so that just leaves the wastegate.... not many other variables.....

 

[Russ Merritt]

Pull the vaccum line of the compressor housing, turn the shop air down to 15-20# and manually check operation of system. Just trying to help you, sounds like you have everything covered though. Wouldn't be any fun if it were easy, you'll get it.

 

[DR. EVIL]

Originally posted by Russ Merritt
Pull the vaccum line of the compressor housing, turn the shop air down to 15-20# and manually check operation of system. Just trying to help you, sounds like you have everything covered though. Wouldn't be any fun if it were easy, you'll get it.

Bare with me here.... what do you mean by the shop air?
And do you know if the Precision housing is "drilled out" for the puck on the THDP?

 

[Russ Merritt]

If you have a compressor (shop air) you can simulate boost press, just turn it down to 15-20# around what the car would be at, then watch the wastegate operation. Should be smooooooth, and when you let off the nozzle (in other words fill the system then let of to hold pressure) the wastegate should stay open if it closes you have a leak somewhere. The trick is to only use 20# max, if you use 90-100# it won't be an accurate test as the car only makes in your case 16#. First make sure there are no leaks in the system (wastegate holds once nozzle is released after system is filled with pressure) If it works you can then check for boost creep by unpluging the solenoid valve (wires) Low boost means the hole is big enough!

 

[DR. EVIL]

thats a good idea, I have a ball/spring manual boost controller, no more boost solenoid. No more computer controlling it, so it's a leak, wastegate is malfunctioning, or the puck hole is too small..... am I missing any other possiblilities?

 

[Russ Merritt]

So you can still test the whole system, go close the manual valve and try it. I also have a manual valve (won't go back to solenoids)good luck!

 

[DR. EVIL]

update

Today I was watching everything on the dash when I went WOT and noticed something wierd (I Think).

I floored it and it took off good, sometimes it would go normal until I let off the gas. however, sometimes it would get to almost 5,000rpms, then it would get "knock" and even though my foot was still to the floor, the rpms would go down several hundred.

Will KR cause the rpms to go down regardless of what your foot does on the pedal??

 

[DR. EVIL]

TTT

okay, today I decided to check some stuff out.

I disconnected the timing feature from the Trans+ and looped it back so the ECM does all the timing adjustments.

I threw my RA chip back in, and it's running like crap.
It's breaking up really bad, knocking (think it's real though) and the only good thing is that all the codes my ECM was throwing with the extender chip in are gone when I put this chip back in.

With the extender chip, it threw codes, wouldn't show the IAC numbers, or the 3rd/4th/TCC on/off

all that works now with the RA chip, but it's running bad.

very frustrating, I just want the car to run right, and it gets worse everytime I try something different.

So far, I haven't noticed the wierd "false knock" situation (where it pulls out rpms and timing both)....

Could I just have a bad coil/ coil module? What the hell is wrong with this car??

 

[Richard Inglett]

DR. EVIL,

Don't worry about the error codes your seeing with your extender chip. They are part of the special rapid update programming utilized by the Scanmaster. If I remember correctly, seven bad nasty codes appear when running the Extender chip. You can get an Extender chip that doesn't have the rapid update feature. However, it doesn't hurt anything.

The part that is confusing is not being able to see your IAC numbers. This is not part of the rapid update programming. Recommend calling Mike at Ramchargers to verify what codes are to be expected and which ones are not.

Good news is that the timing part of the Translator appears to be OK. Rules out one possibility but if it was the problem, problem would continue with any chip.

The inconsistant nature of your knock retard problem does make make it difficult to offer suggestions but I'll try.

- Maybe it's a bad knock sensor.
- Make sure your fuel injector wire is not rubbing the EGR.
- Try another Knock Retard Module (on the passenger side - approximately 3/4" x 3" x 3" dimensions).
- Try another coil pack/ignition module.
- Use some higher octane gas while testing and tuning to solve this problem. One bad boost spike can cause catastrophic damage.
- Like others are saying, make sure your vacuum hoses are not leaking.

 

[DR. EVIL]

okay, ran the car all day with the current chip, it's a "Street" chip from PTE that came with my 009 injectors (not exactly sure what kind of chip it is), all I know is that it's 20 degrees timing (a little high for 93 octane gas).

It seems to be running better, but only sometimes. When I'm in 3rd and it downshifts to 2nd, sometimes it will instantly knock and the KR won't go down until I hit 3rd.

At any rate, I think another tank of 99 octane is in order to see what knock is real and what isn't with a different chip in.