bludgod

iTrader: (3)

have you actually datalogged your car to see what's happening? With the drop in fuel economy it's possibly a boost leak somewhere (smoke and pressure test needed) or maybe even a dodgy MAF sensor causing the car to overread (confirm AFR's with a wideband), or a dodgy fuel reg (again, wideband will show what the true AFR is). Lots of things it might be that can be narrowed down with a little work put in rather than blindly throwing parts at it because some guy somewheres next door neighbors mate was walking his dog and he was chatting to a guy in the shop that had a fiesta one time did something similar and he replaced his aircon switch and it was mint.

Ash Webster

so the guy has just spliced the new one onto the old one rather than do a proper connection and **** knows where this yellow wire is going?

should I go demand my money back?

bludgod

iTrader: (3)

that's something you'd have to talk to him about, what was discussed with you when you gave him instructions on what to do? Maybe he can offer to put it right for you and everyone can go on their happy way?

Ash Webster

He told me he’d done proper connections both ends and it was all sorted new connector blocks the lot obviously me being me just took his word for it.

am I ok to cut the yellow wire behind the splice ? It’s going nowhere right?

Ash Webster

Just cut the wire to the ecu and no change in cyclical knock count still rising to 256 constantly
How do I fix this now? Is it a shielded wire job or a new ecu job? Or both?

How does the shielded wire work? How is it supposed to be grounded?

ossett2k2

iTrader: (9)

From memory the green and white block in your pic are the grounds,the sensor ground is pin 13 b136 which is the same pin as your knock sensor shield pin.

iain710

I haven't got the software or lead to look.....
it was originally mapped by jgm before he passed away in 2014
its been absolutely fine up until a couple of weeks ago...
the reason I've replaced the vacuum lines is because it all started after replacing a leaky header tank.....
a few brittle,20 year old hoses behind it...

Ash Webster

Sorry if im asking too many questions but there is a blue wire coming from that b136 13 pin but no idea where it is going to.. is that redundant now I’ve pulled out all the knock sensor wiring ?

how should I tell an auto elec to wire it cos I’m mega confused with all this shielded grounding etc

ossett2k2

iTrader: (9)

Yeh I'm not brilliant at electrics but that's a poor job,give him the pinout and he should know what he's doing,if not take it to someone who does.

ossett2k2

iTrader: (9)

I've got a full wiring diagram on disc somewhere,I'll have a look tonight and email you a copy.
Would the blue wire from pin 13 not also go to the sensor,they're 2 pin aren't they?

Ash Webster

Cheers @ossett2k2 I’m currently searching for a decent auto elec. but I’m also half aware it could till just be an ECU issue. . And I don’t know - would be useful if someone else who has an v3 Sti could show me the wiring in their ecu and to their knock sensor

Ash Webster

no the sensor is 1 pin. (i think hence why i would like someone else with a v3 to show me their wiring). The wire 'should' be shielded with the shield going to ground.

I dont know for sure if this is the reason im getting a knock sensor error but all i can do is get the wiring done properly and then re-test.

if not itll be a new ECU job - and **** knows where to start with that.

ossett2k2

iTrader: (9)

I see what you mean ash,2 pin locations on the sensor but only 1 used if I'm looking at the pics right.
I can't get to my car until the weekend but I'll see if I can get some pics of mine if I get chance.
So your sensor might not be grounded and this could be the problem?

Ash Webster

i hope so. the count was still going up even tho the yellow wire was disconnected, i need to find the other end of the yellow wire..

however the ground wire (blue into 13) is a grouped ground for all the sensors. i also need to find where the other end of the blue wire is with regards to the knock sensor shield. doesnt help i cant find a wiring diagram for the shielding etc. (for my car anyway). the link you gave me is great for the B136 block but as far as the ground wire theres nothing....

hopefully a decent auto elec can get to the bottom of it...if i can find one!

ossett2k2

iTrader: (9)

If you fire over your email address I'll try get that wiring diagram over to you tonight,,there are a few on the Ken Gilbert site but not sure if they're what you need,you could also have a look on opposed forces,loads of diagrams etc on there but again not sure if they'll be any good?

Ash Webster

yeh ive been scouring ken gilbert etc but they dont seem to be the right ones... opposed forces wont load for me at work >.<

ashwebster1097@gmail.com

cheers again dude

currently trying to ring auto elecs who dont answer phones.....

The Rig

iTrader: (13)

It is a weird fault, i disconnected my knock sensor and cylic knock count didnt budge/count up like yours is. fire a message to andy stevens and ask what the knock count is actually counting, wether it be voltage, activation of knock etc.

bludgod

iTrader: (3)

knock count will be when the ecu has determined the noise from the sensor is greater than the current knock threshold value so the ECU must be seeing something coming in on the knock sensor signal. If the sensor input and sensor ground aren't connected anymore then I'd be looking to put the ESL board in another ECU and see what that does for it. Or put your ECU in someone elses car with a working knock sensor and see if the value continues to increment.

Ash Webster

Aye , i agree with both of you - i have fired ESL an email of my situation

In the mean time i need to find where the rest of the yellow wire went (even though it was cut off by me near the terminal), as well as trying to fathom out where the shielded ground component of the knock sensor should be, but i need a proper wiring diagram for that as the blue wire into 13 is a grouped ground so i dont want to be pulling that one out. either that or the yellow wire leads me to the shielded wire...

If im still getting knock readings after pulling out the shielded ground wire component of the knock sensor circuit (wherever it is) then it will be an ECU or ESL fault like you say bludgod. Is it just as simple as swapping them over (ECU not ESL) and they should work as normal?

Ash Webster

update:

Auto elec coming next weekend (sat) to re-wire the sensor properly. i have printed out loads of wiring diagrams (thanks to Don Clark and the diagram linked above) and done plenty of research so i know (ish) what he needs to do and tbh after speaking to him he seems pretty switched on. The good thing is he is coming to my house to do it so i can plug in the laptop when hes 'done' and test out the cyclical knock count instantly.

First task will be to pull out all the existing knock sensor wiring - it will be a task to locate the path of the previous shielded ground (as it groups into a block near the ECU) and remove that too.
Then check the connection into the ECU at B136 etc etc. before attempting to rewire with shielded wire.
Then continuity checks al lthe way up and down the circuit

Only a week to wait #impatient

The Rig

iTrader: (13)

Has/was it confirmed the original wiring was an issue ? what made you think wiring at fault , burnt out etc ?

Ive had some odd things with my ESL board in the past and it was theo Host ECU at fault, although the ESL isnt a piggy back ecu it isnt a true stand alone ecu it still relies on the host ECU for certain parameters.

you can easily remove the ESL board and refit the resistor to the host ecu and see what it runs like on standard ecu in the meantime ?

Ash Webster

I’ve has this problem for years (probably well before esl was installed but not 100%). So yes it’s either the wiring , the ecu connections or the host ecu

i don’t know how to remove the ESL board and/or where the resistor is to the host ecu. But that is something I will have to look at if the rewire doesn’t work - new ecus aren’t that expensive but I’ve no idea about the wiring or if it will just bolt in and I won’t need a remap again etc...

i can’t currently try anything as I have cut off the knock sensor wire that the bad elec did , so there’s no way I can get the 22 to go away 😂.

Ash Webster

Guy came today - agreed we needed shielded cable to wire it properly but didn’t have any on him so he’s coming back another day - plus was pouring down so didn’t help matters.

checked the voltage coming from pin 13 and it was only 1v.

can anyone confirm if this is too low (check on their own car) . The data sheet says 2.8v or am I missing something

if so so this is a new ecu job right? Regardless of the wiring which needs to be done also

ash

ossett2k2

iTrader: (9)

Pin 4 should be 2.8v pin 13 is 0v as it's a ground.

Ash Webster

Sorry I mean pin 4! Was half asleep

ossett2k2

iTrader: (9)

Is this with ign on and car not running?
I will try dig my car out after the weekend,I can test some stuff then,might be of some help.

I think with car running it should read 2.8v and any change in voltage(due to the frequency noise of det) would mean the ecu sees it as knock.

Ash Webster

Yeh , both cases (ign on and ign on car running) it read 1.0v. The wire out at pin 4 id already snipped off so could get an easy read out of output voltage from ecu. If yours reads 2.8v then I’m thinking I need a new ecu. Incoming new thread about ease of replacing an ecu with esl board kept ��

Ash Webster

Any luck with the voltage check @ossett2k2 ? just want to make sure its my ecu before i go to the next step which is the hassle of buying and installing one

ossett2k2

iTrader: (9)

Moving day Saturday Ash,fired it up yesterday got it ready to move but didn't have time to check,I'll try my hardest to have a look mate,it'll probably be Sunday.

Ash Webster

Thanks pal! hope all is fine with the move.

Elec coming back on sat to rewire the knock sensor properly so we'll double check the ecu pinout voltage see if its anything to do with connections etc or if it definitely is the ecu.

Have a few ecus on ebay watch list >.<