maff125

iTrader: (1)

Hi,

I have a knocklink installed on my 99 uk turbo, which also has a prodrive ecu fitted and supporting mods. When on full boost at WOT, the lights on the knocklink go from red through to amber green and stay on blue when at WOT, but just lately i have been using the car for work and have noticed that when on full throttle i am only getting an amber light on the knocklink?
Not to clued up on knocklinks but roughly know how they operate as in red means detonation and blue/green is all good.
So could anyone please tell me why i am getting an amber light? is it a sign of a maf failing or something else? also dont know whether im being paranoid but car does feel slightly slower with the amber light showing?
Also been using tesco 99 ron fuel

Any help would be much appreciated, cheers matt.

Splitpin

Alright, will ask the obvious silly question first:

Are you sure you're talking about a KnockLink, because the behaviour and colour of the lights you're describing sounds like one of JW Racing's narrowband AFR gauges, or maybe an old LambdaLink.

KnockLinks don't have a blue LED, they have two green, two yellow (or in the one below, a yellow and a small red) and a big bright red one and look like this:



...and are connected to a secondary knock sensor bolted to the engine. AFR gauges don't look like that, and are tied into the lambda sensor wiring, either under the bonnet or down by the ECU.

Is this what you have? If not we need to know before going further otherwise we could be wasting our time giving you advice built around the wrong assumptions.

maff125

iTrader: (1)

Ok,

What i have fitted does not look like your knocklink in picture, it is very basic as in a small black box showing four leds which illuminate red, amber, green and blue and is fixed by velcro below and to the left of the steering column,(very hard to see!)

So would this just be an air/fuel meter as red (running lean) and blue, (rich)

Sorry of my limited knowledge of these things but learning all the time!

So if i my engine was running lean then would this mean the MAF was failing or something else?

Cheers matt

Aztec Performance Ltd

iTrader: (234)

If the lights "disco" on idle, it will be an AFR gauge of some sort.

maff125

iTrader: (1)

No lights on idle , when the engines cold the lights disco a bit and when flooring throttle with warm engine the lights go from red, amber, green and stay on blue right round to red line, now im getting an amber light instead of blue?, ill have a ganders tomorrow to see if theres any branding on the actual box cause dont seem to be able to post pics up on here.

Thanks for all input, much appreciated

Turbotits

iTrader: (2)

I dont think its a knocklink you have fitted as the start green and finish red as above with no blue> sounds like an afr gauge of sorts

maff125

iTrader: (1)

Right so assuming ive got an afr gauge and my engine is running lean, what does this mean? as i used to get a blue light all the time but now an amber, would lean mean less fuel and more air mixture? and what would cause this, a failing maf or sparkplug issue, or am i just worrying about nothing!?

Splitpin

From what you've described it sounds like my first guess was close and you have a JW Racing AFR gauge.

What you're reporting is most likely caused by one of three things: A failing MAF sensor, a failing O2 sensor, or a drop in fuel pressure.

Without some corroborating information it's impossible to tell which of the three it is. It could be a combination of all the above, or something else besides. The best thing you could probably do at the moment is have your car checked out by a Subaru specialist, they'll be able to tell which, if any, of the components is failing.

If you're not going to do that, the next move is probably to start a process of elimination, by replacing the MAF sensor, resetting the ECU, and seeing if there's any change in the behaviour of the AFR meter. If there isn't, replace the O2 sensor, and so-on. You could end up spending a lot of money speculatively replacing stuff via that method, so a specialist is your best next move.

maff125

iTrader: (1)

Thanks for the info guys, the closest Subaru specialist to me is powerstation, so might give them a try, any good?, and maybe my fuel pump is struggling to cope because it's a standard one and a friend who had a 340bhp wrx doesn't get away from me by much so maybe I need an uprated pump?

Splitpin

If your friend has a newage WRX, he most likely can't get away from you because of all the extra weight in his car slowing it down. Powerstation know their stuff, let them take a look at it.

maff125

iTrader: (1)

Friend has an L reg classic wrx, which he has spent thousands on and know about the power to weight issues with the newage cars, he can only crawl away from me, thats why i thought the standard fuel pump might be struggling. Gotta get my car on a rolling road as sure its running more than 260bhp
Will give powerstation a try, thanks for all your input

dee052

iTrader: (1)

The colour of l.e.d.s and description is the same as my DAWES afr.