Thread: Kr Blues

Hey guys im looking for some help. Im seeing Kr on my car when I never used have any.

Even after I added the 1.9's I didn't have any Kr untill recently. In addition the 1.9's the car currently has 3.4 and headers intense can tune 104 plugs zzp 10.5 wires.

I thought was maybe I got some bad gas. Here in Oregon you can't pump your own gas so the possibility that I got reg (87) instead of supreme (92) and didn't notice is possible. So I ran that tank through and made sure I got the right gas.. Still have Kr.. My scan gauge shows Kr up to 3.2 torque shows it up to 2.1.

The most current change to the car is the plug wires. Swapped the Taylor's (blue) for zzp's purely for the red wires. I would put the Taylor's back on to check but

If you have any tips I would greatly appreciate and will report back as always

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Okay, it knocks but that's not going to help much here.

What's everything else like?

How is real time fueling, does it match what you are commanding?

Is timing too high or too low?

When does it knock and how often?

All the time under load or just spikes here and there?

Data logs??



I ask this because this is how a tuner would look at things. I'd be referencing a data log and a wideband input to see the knock and determine if the problem is within the tune file or possibly false knock being picking up by the sensors for an unknown reason.

bad o2 sensor gave me kr out of the blue.

I had a loose IAT sensor wire and this gave me about a degree of knock car seemed to startup and run normal but there was a code showing. I assume you don't have any codes? if you do let us know

Originally Posted by tzerilli

I had a loose IAT sensor wire and this gave me about a degree of knock car seemed to startup and run normal but there was a code showing. I assume you don't have any codes? if you do let us know

No codes picked up or pending. When you say loose can you elaborate some? I inspected my IAT plug and I did notice the the wires do slide back and forth a tiny bit in the plug but so does all the others on the TB. Prolly because it's 22 years old now lol

Originally Posted by Scottydoggs

bad o2 sensor gave me kr out of the blue.

I have a few upstreams around my tuned out downstream now houses the wideband and the car is catless

Originally Posted by Fivefingerdeathpunch

Okay, it knocks but that's not going to help much here.

What's everything else like?

How is real time fueling, does it match what you are commanding?

Is timing too high or too low?

When does it knock and how often?

All the time under load or just spikes here and there?

Data logs??



I ask this because this is how a tuner would look at things. I'd be referencing a data log and a wideband input to see the knock and determine if the problem is within the tune file or possibly false knock being picking up by the sensors for an unknown reason.

Everything else seems fine.

Scan gauge shows Lt and St trims are good.

Timing unknown

Knocks under load only, 3500 rpms and higher

Commanded fuel seems good idle and cruzing wideband shows fluctuating 14.7 and 15.5ish on average and pinned to the floor 11

I wish I had logs but im still don't have a tuner yet

I had the thought that it could be false knock but I don't know how to diagnose that.

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what ya scanning with? t app? scan upstream o2 (mv) if they have that one in the t app. wot should be in the 930 range, if it drops to almost nothing thats the issue.

t app will also show timing advance.

I use to scan with T app but now I just use the aeroforce.

I'll look at that Scotty since I can watch that on the scan guage.

I did fail to mention that I do have more then one exhaust leak aswell

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if the leaks are at the headers and are new might be the cause, if in the cat back not a problem.

Ugh I would hate to have to replace the header gaskets lol.

Is there another way to check other then the seafoam deal?

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when its cold, fire it up and with your hand feel for air coming out. you dont have to long before things get hot so be careful.

Did some testing. I can't feel any air comming out around the header flanges nor do I see any carbon around them that would suggest a leak there.

At WoT upstream o2 reads 935
ignition adv. -14.5
stft 0 ltft-1.5

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that neg timing? you got a - there. if its just 14.5 is there kr at this time. thinking the timing would be higher, closer to 18 like most canned tunes are.

what about the flex on the down pipe to header it can leak. sea foam might be a good idea.

Some scanners read the timing in reverse, I know 1997's did it for whatever reason.

Originally Posted by Scottydoggs

that neg timing? you got a - there. if its just 14.5 is there kr at this time. thinking the timing would be higher, closer to 18 like most canned tunes are.

what about the flex on the down pipe to header it can leak. sea foam might be a good idea.

Yes defiantly negative idle is neg 22. I checked a few times to make sure it was accurate.

I have pace setter headers so I don't have a down pipe just a collector. The flex pipe is welded to the resonator.

Car is a 97 I didn't know it read timing backwards lol makes sense tho.. Another reason why no one likes 97's

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I am petty sure the flex leaks. I'll seafoam it but it's going to have to wait untill next weekend

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that flex looks pretty new.

It's got some frays in it. Kinda hard to see in the photo

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[QUOTE=wowitsfast;1496414]No codes picked up or pending. When you say loose can you elaborate some? I inspected my IAT plug and I did notice the the wires do slide back and forth a tiny bit in the plug but so does all the others on the TB. Prolly because it's 22 years old now lol

yea that should be fine loose in my case was with some wiggling some wires came disconnected and with a pull (same force used to shift) the whole harness came apart. haha still check for frays and everything else in the future looks like that flex pipe may be an issue though. I know when my header flange gasket was leaking it made a very distinct ticking noise mechanic that welded the header the rear exhaust noticed it immediately and without any diagnosis could tell it was a header flange leak.

Maybe it is a header leak. I only hear the leak under load.

Im running copper 104's on a 3.4 and 1.9's. is there a chance that the plugs are to cold and causing this knock? I have noticed that my sc runs a lot hotter now with the 1.9's like can't touch it hot. Before them I could lay my arm on it and not be bothered by it

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im gonna go out on a limb here, you never touched that thing after a wot pass. my blower with a ic could fry eggs after a 1/4 mile pass. added meth to the mix and you could give it a long slow kiss now, its warm at best after a 1/4 mile pass. even the gen 5 blower now with meth is only warm. water and meth cools the hell out of it damn good.

all the rockers do it let you move a bit more air through the engine. my rockers i put on as a first mod, i had 8º kr, rockers killed 5 of that off, U bend delete killed the last 3 off. stock pulley stock manifolds, no tune yet. a 3.4 will put you about 12 psi and with out a tune it can be to much for it.