Okay I'm SICK of my code 52. PLEASE help me fix it.

[toml]

OK, So I had a code 52 for a while... I did the knock-sensor rewire since I figured my wires were shot. The code 52 disappeared for a while and the car was running nice.


...It's now come back. It's intermittent. I can't _make_ the car get a code 52 by revving hard or boosting lots, but _every_ time I drive it the C.E.L. comes on and the engine starts running like a pig. It only seems to come on once the engine has warmed up.

I've just bought two second-hand knock sensors and tried changing one at a time but that didn't fix it.

I got out the multimeter and both knock sensor cables are reporting about 0.1ohm resistance between the knock sensor and the ECU, and I tried jiggling about the connections with the multimeter connected to check whether there was any broken wires, but it stayed at a nice low consistent 0.1ohms.

What on earth else could be causing my code 52? What else can I try to resolve it? The engine runs _SO_ poorly when the CEL comes on - I assume its retarding the timing to some huge degree.

Please help me resolve this!

 

[toml]

I also hooked an osciliscope up to KNK1 and KNK2 terminals on the ECU, and saw a pretty consistent flicker up to almost 1 Volt. I'm not sure what I'm meant to be seeing there...

 

[pimptrizkit]

what kind of gas you running? what station? have you tried changin you fuels?

how much boost? air temp out side when cel comes on?

what is your base timming?

What on earth else could be causing my code 52? What else can I try to resolve it? The engine runs _SO_ poorly when the CEL comes on - I assume its retarding the timing to some huge degree.

yes the engine is retarding the timming.

do you know what your fuel pressure is? vaccume?

has the motor been freshend up at all?

and are you running an egr? an egr can help reduce cylinder temps which will help from pre detenation, which causes knock.

 

[chriso]

I had trouble with my rewire also. I found that the inner core had melted somewhat after the coax cable touched on the egr pipe. This was causing an intermittent ground.

 

[toml]

what kind of gas you running? what station? have you tried changin you fuels?

how much boost? air temp out side when cel comes on?

what is your base timming?



yes the engine is retarding the timming.

do you know what your fuel pressure is? vaccume?

has the motor been freshend up at all?

and are you running an egr? an egr can help reduce cylinder temps which will help from pre detenation, which causes knock.

I was under the impression more knocking in the engine won't cause a code 52, only a short circuit in the knock sensor wiring or a faulty knock sensor or ECU?


In relation to other questions: 98 octane premium unleaded. Haven't tried changing fuels. No I don't have an EGR system. I don't know what my fuel pressure is. The motor has been rebuilt about 10,000km ago (new bearings, pistons, rings, metal head gasket, studs, etc). Base timing is standard 10deg btdc.
Air temp outside when the CEL comes on ranges from 10C to 28C (50F to 82F). Running about 9psi boost with a manual boost controller (but hardly seem to boost that high, I think I have a boost leak).

 

[toml]

I had trouble with my rewire also. I found that the inner core had melted somewhat after the coax cable touched on the egr pipe. This was causing an intermittent ground.

I might rip it all out and make sure the cables are in good condition.

 

[cruzinbill]

You are correct. Code 52 does not indicate u have Knock it indicates a problem in the knock sensing system. Ex.-your sensors are bad or a wire is bad.... ill link the post with more info in a bit. I am having simalar problems. I have a Brandnew Eng Harness and 2 Brandnew sensors and i get it only when i drive. I got another set of sensors but cant install them till next month when i get home. So untill then i am researching it.

 

[toml]

So I've re-wired and got two new sensors... the only other thing that could be bad is the ECU.

I will confirm that my new wires are OK and then start complaining about the ECU

 

[toml]

Oooooooohhhhhhhh!!

My cables look perfect (of course, I made them! ).... but when I unclipped the connector from the front sensor, i discovered it was somewhat wet and slimey.

As far as I can tell, the coolant pipe on the bottom of the lower intake manifold is leaking coolant on to the knock sensor + connector! I'm going to rip the manifold off tomorrow and check it out.

I'm preying that the coolant leaking onto the connector is shorting it out intermittently!

 

[mkiiSupraMan18]

I saw the time as 4am and was like "Damn... that's dedication" then noticed you're from Oz.

Code 52 sucks, but I only had mine flash once or twice on my old car. I'm hoping for ya that it's an easy and cheap fix for you.

 

[toml]

Hehe, it's only 10pm here. What on earth are YOU doing up at 4am?!

Thanks, I hope its an easy fix too!

 

[mkiiSupraMan18]

it's almost 9 now,

I'm at work/school at the hospital, not exactly a busy place this early on Sat mornings. :icon_razz

Just drunk drivers for the most part. They ussually make it entertaining though.


And about your KS rewire, how hard was that to do and what kind of wire did you use?

 

[steve_mk3]

Code 52
Only 3 possible sources of the problem
1- Knock sensors
2- wireing from KS to ECU
3- ECU

The code is only generated when the ecu can not "hear" the KS. It DOES NOT OCCURE IF YOUR ENGINE IS KNOCKING!!

The knock sensors produce a wave form output that is very sensitive to electrical interferance. That is why the rewire is done with shielded coax cable.
Understanding the nature of the problem, it is extreamly important to ground the ecu side of the KS rewire.
I had a consistant %@ untill I grounded my reswire to a VERIFIED chassis ground.

IF you check your wireing and it is known to be good, check to make wure you have grounded the outer part(shielding) in the rewire. Use a meter, don't assume that you have a ground. Make sure that the center wire is not grounding to the exterior shielding.

It sounds to me like this is a wire problem, due to the intermittant nature. Again the ecu is listening for the sensors. The sensors would be either good or bad, I dont think they can be the source of an intermittant problem. Make sure the sensors are firmly screwed into the block. When you did the rewire, did you replace the plug on the end that attaches to the sensor?

Steve

 

[steve_mk3]

also
http://www.supramania.com/forums/showthread.php?t=26154

 

[pimptrizkit]

well thanks for the clarifaction guys, i was just tring to b as helpful as possible ,

looks like the coolent issue is the awsner tho
have a good one.

 

[toml]

Mwuhahah!

Ripped off the intake manifold yesterday and fixed up the leaking coolant hose (clamped that sucker down TIGHT!)... I drove the WHOLE way to work this morning without any sign of timing retardation or code 52 lights That's the first drive of the car in 3 weeks which hasn't resulted in code 52. Suffice to say i'm STOKED!

...only problem is that somehow I managed to make the gasket between upper&lower intake manifolds leak, so I have to replace that when I get home today.

 

[cruzinbill]

so what did u do to fix it... the clamp thing?

 

[suprahero]

coolant was leaking onto his knock sensor and causing it to short out. He fixed the leak and his code 52 went away. I haven't been so lucky. I think mine is in my ecu. I'll find out later, I hope. I rewired mine with a kit from Shaeff. Very good product if you need a rewire kit. First class...............lol

 

[cruzinbill]

lol if i need a rewire kit i will be really pissed off, since my harness is brandnew

 

[toml]

.... its back

Maybe I could set it on fire... ?