For the Winter, I removed my 2.8 and 60's and went back to the Stage 2 pulley and 42's.

My tuner, put the same tune that I had before the summer back on, and we found that it was knocking in 3rd 4th and 5th up to 6 degrees of knock. So we put the stage 2 tune back on, and the car was still knocking. We ended up chalking it up to bad gas.

Well I ran the tank to less then an 1/8th of a tank then filled it up with Shell, and now I am about a 1/4 tank down, I am still getting knock?

Knock happens at WOT or mostly WOT, and the car seems to be running well over all. When I am at WOT I sit around 10.8 to 11.0 AFR on GMS2. I don't have any check engine light, or codes. and the interceptor says there are no misfires.

Things I have changed since the last time I had this tune:
RAW intake
Option B and Dual Pass
OTTP Stage 1 Rotated Mount
1 Step Colder Plugs (.038 gap)

Anyone have any ideas?

 

Hmm..thats odd...my Interseptor tells me my car misfires all the time and i never see any knock on the guage or hear it knocking..just wanted to say that but as far as everything else..idk what that could be. happens at WOT soo idk could it be that your injectors are bad?..clogged?..making it knock not enough fuel?..but you would have a check for that

 

Put the stock plugs back in

 

OK I put the stock plugs back in last night, seems the problem is less, but not gone. The odd thing is that there is no consistancy with the problem. Sometimes its there, sometimes its not.

If I get hairy and go WOT through all the gears I get the usual tip-in, but after that nothing. But if I decide I want to pass someone on the highway I leave the car in 5th got wot, I can see the interceptor start counting up.

Something that I was able to figure out last night was that in all the times that I have been able to watch my interceptor it never ever goes past 5.9. Not once have I seen a 6.0 or higher.

Another odd thing is that I am getting some jerking when @ low RPMS in 1st and 2nd gear, just like when I had my 60's in. I don't remember this happening before I went with the 2.8.

With everything, I'm thinking that it probably has something to do with fuel. I have about 52000 KM (about 32000 Miles), so I am going to try replacing the fuel filter, see if that helps.

Any other ideas?

 

try running .32 gap that seems to help some people

 

might be false knock....

 

or . try .35 gap

 

K I will try the above this weekend. buddy and I are sitting down to figure this **** out. I will post the results.

 

could also be a bad knock sensor.... do u have poly mounts?

 

no, just ingalls and stage 1 rotated mounts.

 

Clean the throttle body while your at it. This will help with the hesitaiton in low RPM's

 

You could always be running too much timing lower it 1degree where you see the knock it will take care of it. Also lean it up a bit 11.0 is perty rich I run mine at 11.7 with with 18* timing and I dont see knock.

 

john i get the same thing when i go to pass someone on the highway without changing gears but it just tips in ( goes to 3 counts of knock then out right away so i dont worry about it as its gone within a second) Did you attempt some injector cleaner as i assume your old 42's have been sitting for a while?

 

play with the plug gaps....mine went away when I decreased my gap

 

Ok I need to mention a couple things. First off a few of you are stupid. Maybe I am being a *****, let me correct that, some of the things you guys do are stupid.

Never go wot in 5th gear, never. It's EXTREMELY hard on a motor to be wot in 5th gear, the load is ridiculous, don't do it. If you want to pass someone, down shift, pass, up shift. Plain and simple.

First thing the op should do is a compression test. There is a very good possibility that there is a cracked ring landing, broken piston, etc in one of the cyl's that is causing the knock. If your compression test comes back with high numbers on all 4 cyl's it could be a few other things. The gm stage 2 tune should NOT knock on decent 91-93 octane gas. There are CERTAIN times where you might see a quick degree but that is it.

If you are seeing that much knock, it's not false knock *unless something is rattling around in the engine bay*. When you first slam the gas down, the motor rocks back towards the windshield. When you let off the gas the motor rocks forward towards the headlights. This will cause a little bit of false knock. Also certain shifts will give .3 or 1 degree of knock at times. Shifting at a really low rpm is also hard on a motor. NEVER shift below 2k rpms, generally shift at 2-3k for city driving.

It really sounds to me like you either have something in the engine bay that is rattling around causing the knock sensor to be set off during wot, or you have a broken internal part. Your first step here is a compression test though. Granted your tune needs work, but before you even touch the tune, solve the knock issue. If the compression test is fine and there are no rattles, no codes, etc, feel free to change the knock sensor.

Hopefully this works out for you in the end, but for the love of god down shift. There is a reason why the gear ratios are different and that 5th is considered a CRUISING gear.

Good luck, have fun, stay safe.

 

Yeah I forgot to say that in my last post never kick it down in 5th its fine to give it a little gas but you dont want you tps at 100% caause u will knock all day no matter what you do.

Like zach said check see if there is anything rattling in your cars engine bay if not maybe something got changed on the tune you could always download another stage 2 tune and compare the files.

 

Put the copper plugs back in and gap them to .32. .38 is too big of a gap.

 

QFT! With my 2.8/60's setup I started seeing knock as it got colder, even with meth i could running like 20-21* of timing in order to not knock. I thought my plugs were gapped at .35 so I was going to drop them to .32. Well when I checked the other day they were at .38 Dropped them to .32 and am back to running 23* no problem even in 40-50 degree weather

 

Yah I never go wot in 5th, I always shift down to pass if i need major acceleration- a little throttle in 5th is nto goign to hurt anything. People on here are not idiots and know stuff about cars so some of your comments come off a little arogant. ( Speaking for myself and op).

 

OK, last night my friend re flashed the car with a write-entire and did a crank relearn to see if this would fix the issue. No dice. So when I got home, I put the stock intake back on and am running a bottle of fuel system cleaner through.

Tonight I am going to pull out all the injectors and re-seat them.

If those don't that I am going to replace the fuel filter. (Kinda want to leave this to last considering the price)

Awesome. I'm not taking your post as being a *****, I was just trying to explain one situation where I was getting knock, basically under load. I will look into these things and update again.

Something that I want to say though is that the car was fine when I had my 2.8 and 60's on there, no knock what so ever. its only since I put the stage 2 parts back on that this started happening. Seeing that the tune is basically eliminated (Stage 2 tune) the only thing that has changed now is the injectors. So this is where I am concentrating right now.

Next week, failing all the above, I will go and get a compression test.

 

I had a similar problem last year so this maybe a long shot but how is the intercooler pump working? Are the IAT2's at a reasonable level? about 40 degrees above IAT.

I found out my intercooler pump was intermitten, would only work occasionally. Since changing it out the knock problem for me was more manageable.

 

same exact thing happened to me....ingalls will give you phantom knock

 

Yeah, temps look good...

I ment to take this off last night too, but forgot. I have seen the type of knock that the ingalls generates, and this looks different.