Found my fault hopefully

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pulsarmike

New Member
Hey guys,

As a few of you know i had a few problems.

Took car up to jonathon who put a few things in the right place, much better on fuel now ticks over a bit nicer.

However, it was still underpowered, it running the bar of boost loop ive found out from another member (thanks) so should be quick but wasnt.

Was getting irregular ecu light flashing. sometimes flashing fast when on throttle and sometimes just stuck on when off throttle.

Me and jonathon tried to do the fault code test by linking the 2 pins but couldnt get it to work, also the check engine light does not come on when you turn the ignition which is odd.

So anyhow, i bought nissan consult off ebay, cost me £20.00.

Plugged her in and ive got:

CODE 34: KNOCK SENSOR CIRCUIT (4 STARTS AGO) :doh:

ON TICKOVER IVE GOT;

m/r f/c MNT : RICH

RPM 1050

MAS AIR/FL 1.45V

THRTL POS 0.48V

IAC-AAC/V 10%

O2 SENSOR 1.17V

A/F ALPHA 100%

IGN TIMING 18 BTDC

Trying to put some pictures on aswell.

So now going to sort the knock sensor :doh:
 
bensmith907

bensmith907

New Member
I think you may have two faults here-

Firstly you could knock the timing forward a couple of notches to 20deg (maybe a tad more if you cant get the revs down) that'll help straight away (your thread says 18deg but the pic says 12deg @ 1050revs) either way that should be a fair bit higher at those revs.

Here's a guide

Also I think the flashing light your getting is because of a short on your self diagnosis wire which is accessing the 'Exhaust Gas sensor monitor' function when normal driving- I had a post on here before for the flashing light whilst accelerating which came down to this function being accessed accidently. If you can't find any problems with the wires try slaving in a known good ECU and see if it goes away.

MAF reads fine- should read 1.1V-1.5V- Try reving it to 2k and you should have 1.3V-1.8V (it will flag up a fault code if it leaves these parameters)

O2/Exhaust gas sensor reads fine- should read 0-1.5V (again it will flag up a fault code if it leaves these parameters)

Im liking the Consult program mate, already I know more about your car than I do mine :lol:
 
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pulsarmike

New Member
The btdp read 18 before it dropped a little.

I didnt think about that being another fault, i assumed the knock sensor retarted the igniton.

O well maybe another fault as you say lol
 
PobodY

PobodY

Moderators
Staff member
pulsarmike said:
The btdp read 18 before it dropped a little.

I didnt think about that being another fault, i assumed the knock sensor retarted the igniton.
Click to expand...
Yes. If you the ECU thinks you've got DET (even if that's because the sensor is playing-up) it will retard the ignition. - I don't know if it retards it that much at idle, but I'd recommend sorting that first then re-checking because it might sort its self out.
 
bensmith907

bensmith907

New Member
yea maybe your right, what about if you clear the fault code then observe the timing again otherwise you could spend ages chasing a knock sensor fault
 
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pulsarmike

New Member
The program doesnt give the option to clear the fault, all it gives is that box you can see above, the starts obviously mean how many starts ago the fault occurred.

The sensor is getting changed 2moro hopefully, so, will post back with results.
 
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pulsarmike

New Member
Update.

Fitted new knock sensor, still slow. Ecu light still flashing on and off when on throttle

Diagnostic reader still shows fault but from 24 starts ago.

Do i need to clear the fault for it to recognise theres a new knock sensor been fitted before it will UN-retart my ignition?

Guy who fitted it thinks its quicker than his standard one but his is in bits so i can have a go of his to see.

He's saying ive come from an evo so i shouldnt expect much, my evo was standard and this is running a bar of boost so really i think it should be slightly quicker than an evo.

One thing im not sure of however is what the timing should be at around 3-5k revs, the real time view thing on conzult is saying 50 btdc, this seems high but i dont know lol.

Tick over its between 16 and 20

Added another picture, its a slight bit blurred but you can make out whats what using the clearer pics above if your struggling.

Getting annoyed with this car now

 
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pulsarmike

New Member
By the way im assuming its running a bar of boost from what ive been told.

The standard boost controller has been removed.

The pipe is now just connected to the manifold.

The standard boost gauge in mmHg goes to just under +7 on full boost.

Does anyone live near me with one of these that works? Your more than welcome to have a go see what you think!
 
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geoff pine

Well-Known Member
Where in Manchester are you it,s the sort of thing we could sort out at a north west meet :doh: first thing buy your self an after market boost gauge :thumbsup:
 
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pulsarmike

New Member
Im in wigan mate.

Ok took battery off and its cleared the knock sensor fault.
Ecu light still comes on, the standard boost solenoid isnt fitted would this bring the light on?

Fitted aftermarket boost gauge and its reading between 0.5-0.6 bar boost.
Just lined it up with my friends scooby wrx estate and mines marginally quicker.

Looks like it was just down to running very little boost, although the knock sensor not working probably didnt help.
Still going to check the timing though as it may be out a little.
 
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geoff pine

Well-Known Member
SO no one bar loop then sounds like standard boost i have not seen that sort of consult you have . My Blatz brings up all the info on dials, my o2 used to flick back wards and forwards on the dial not read a constant signal which i thought was normal for a narrow band sensor.
 
PobodY

PobodY

Moderators
Staff member
Fast Guy said:
Sounds like you're in mode II

http://www.gtirworkshopmanual.com/default.aspx?v=857
Click to expand...
I think someone else suggested that too. - If you've tried to reset the ECU etc by disconnecting the battery, it might be that there's a short somewhere that keeps putting it back into mode II... or the ECU is playing-up. It might be worth checking a known-good one (which may also have already been suggested).

geoff pine said:
my o2 used to flick back wards and forwards on the dial not read a constant signal which i thought was normal for a narrow band sensor.
Click to expand...
That's how I understood it too: It just goes lean, rich, lean, rich, lean, rich... (which is effectively 1, 0, 1, 0, etc - hence the narrow part of narrow-band). When there are more "rich" than "leans" the ECU knocks the fuelling back, and when there's more "lean" than "rich" it throws more in.
 
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pulsarmike

New Member
Yeah it looks familiar.

Flashes on and off quite fast too fast to count really it does it after 2k rpm as stated.

when off throttle it just stays lit untill tickover were it isnt lit.

Why do you think this is happening and how do i get it out of this mode?
 
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pulsarmike

New Member
PobodY said:
I think someone else suggested that too. - If you've tried to reset the ECU etc by disconnecting the battery, it might be that there's a short somewhere that keeps putting it back into mode II... or the ECU is playing-up. It might be worth checking a known-good one (which may also have already been suggested).
Click to expand...
Yeah you may be right, the ecu used to have a piggyback and someone has twist and taped the connections back, i will heat shrink them 2moro and hopefully that will solve it.

If not i will have to borrow an ecu and try that, will being stuck in that mode affect the performance

Also big thanks for the help, im finally getting somewhere lol cheers
 
bensmith907

bensmith907

New Member
pulsarmike said:
Why do you think this is happening and how do i get it out of this mode?
Click to expand...
as said before I reckon you have a short on one or both of the fault diagnosis wires or the ecu has a short on it. disconnect the ECU then check resistance between the two wires and then both to earth. good luck mate

I don't think it effects performance being in mode two mate, its just really annoying I know- ha ha
 
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