Trout

iTrader: (1)

Went to PE today to run the car on the rollers for the first time.

It was not all good news. STI V with HKS Induction Kit and HKS Hiper exhaust.

Run I - abandoned at below 7,000 rpm due to terrible detting - CO at 5%, as opposed to 8-10% - Power 295bhp

Run II - AFM, assumed to be guilty party, was cleaned - same again although detting a little further up the rev range - run abandoned - CO at around 5% AGAIN! - Power a staggering peak of 325bhp!!!

Run III - borrowed Paul Banham's AFM (Thanks Paul) as his car was OK - run abandoned at 6,000rpm as it was about to blow up!!!!!

The diagnosis is still unknown - although fuel pressure is a possible.

Lessons

Just because the car seems to be pulling like a train doesn't mean to say it is healthy.

Detting is not obvious to the untrained ear, especially when you are cacooned in the car with the cacophony of induction noise and big exhaust boom. Having said that it was pretty bl***y obvious on the third run.

STI Vs which are reputed to run rich - which I assumed mine did with all the black soot around the exhaust - may well not be at high revs.

I was pretty happy with the car until now I have had it on the rolling road which has exposed a potentially disastrous problem.


Finally I would have to say thank you to David and his team at PE who patiently tried a number of things - such as swapping the AFM - on a busy SIDC dyno day.

An unhappy Rannoch with a car which is still not diagnosed as healthy.

GavinP

Sorry to hear of your troubles

How many miles has your car done and when was the fuel filter last changed ?

Is the car standard apart from air filter and exhaust ?

Quoting verbatim from the "Training WRX" book, they say that the three(?) main factors in detonation are inlet and block temperature, fuel octane and boost level. How does this match to your car ?

From your posting above, it sounds as if you already suspect fuel pressure is the cause.

Possibly you would benefit from some additional gauges on your car to help identify potential problems - maybe some of the other members have some ideas ?
My initial thoughts were for an exhaust gas temperature and fuel pressure gauge ?

Taking further steps to reduce the oil and water temperature may also be prudent - if the boost and fuel readings are normal.

I hope your car gets well soon - a reliable 325bhp would be a great result

Thanks

Gavin

[This message has been edited by GavinP (edited 12-12-1999).]

Trout

iTrader: (1)

Car is standard other than mods described - so 325bhp is not realistic - perhaps somewhere between 290 and 310 on a cool day is better.

Car has done 12,500 miles.

Boost was peaking at 17lbs, holding 16 which is absolutely correct for a pretty standard STiV. Fuel was SUL with 1% Silkolene ProBoost.

Temperature per se should not have been a problem as other cars were running well - so my conclusion is that it is a physical fueling problem to, hopefully, be tested during the week.

There is no evidence that the car is overheating as generally on the road it is fine. The ECU reports no faults and two weeks ago a run through a Select/Detect did not pick anything up either.

Fueling at low levels is fine - very sooty exhaust, lots of pops and bangs on overrun (great in underground car parks!) - so I await arrival of man with Fuel Pressure Meter!

Cheers,

David

[This message has been edited by Rannoch (edited 12-12-1999).]

Stef

Hopefully you'll sort it before Feb 20th eh Dave?

Stef.

bob

Hi Rannoch
I was at PE when your car was detting, I had the same problem the day before. It did sound a lot louder on the rollers than It did in my car. If you are with IWOC you will have heard of my problem, Could this be the same as yours. My car is re,mapped to 95 Ron and been running on 95 Ron for 5 tankfulls with no problems. I put 98 Ron in for a hard run then reverted back to 95 Ron only to find the car was detting. So I refilled with 97-98 Ron to find the problem gone.
So the ECU learned to give extra with 98 Ron but was slow to learn to reduce with the 95 Ron. (or I had crap fuel.)
I have noted that you use Silkolene Proboost this increases the octane of fuel. Could you have put to much in at one time giving the fuel a high octane rating. The ECU will learn this, and when a slightly lower octane rating is used the car will det just like mine did, that's until it has learned to retard the ignition.
This is only what I have learned through my problems with detting.

GavinP

David,

As you say, your car seems to be happy - with the exception of fuelling at high revs.

When I imported my car (33,000 miles) and then took it into Roger Clark Motorsport for a service and check-over - they changed the fuel filter as a matter of course. Thinking about it, if the fuel filter is slightly clogged up - this would not be apparent until higher revs and maximum flow of fuel is required. Then it would become a bottleneck - if my thinking is correct.

When I mentioned temperature in my last post, I believe what the author of the book meant was if you add a larger oil cooler or water radiator then detonation is potentially reduced. This seems to be bourne out with PE recommending Aquamist water injection to reduce the inlet temperatures on the STI V. But it wasn't exactly humid on Saturday - so it's probably not relevant.

One further thought - if the fuel pressure is OK, it may be worth checking the spark plugs. I remember reading somewhere that octane boosters can foul the plugs.
Not very likely, I'm sure you'll agree but something to bear in mind if the fuel system is passed as fit.

I hope your STi gets well soon

Gavin

Trout

iTrader: (1)

Gavin - thanks for your sympathy...

...some thoughts on the comments made.

I have only been using octane booster for about a month - and mostly the car runs better. I have also reset the ECU a number of occasions recently relating to the cold start problem and I can understand your logic I am not sure that this is the cause.

I will eliminate fueling first as the car was running SO lean at higher revs, but appears to be very rich at lower revs. I am not sure that the ECU thinking about 1-2 points of RON will reduce CO output from 8-10% to 5% - but I am happy to be corrected.

Cheers,

David - whose car is running better today for some unknown reason!

robski

hi rannoch,

I was with you when you car was on the rollers, a damn shame, but at least you know its at high revs, so you should be ok on the road for now, and the potential seems massive.

we were discussing suspension mods, can you mail me what you said, it makes sense and I am thing of going that way

robski

Lee

Lets not forget one of the biggest problem with rolling roads...

If I remember rightly your car detted at high rpm. assuming it was done in 4th most likely at an equivalent 100MPH or more.

Imagine the cooling effect from oncoming 100MPH cold air into the engine bay, rads, intercooler etc and then think about the weedy fan that PE use.

As someone said, temperature has a lot to do with detting.

Someone had advised me to tune the car with half the intercooler blanked off to represent a rolling road !!!!

Bob Rawle

Lee, that won't make the difference, the rolling road soaks heat into everything, thats the main culprit.

I've seen 4 rolling road runs produce a 45 bhp difference from first to last. The Impreza only loses about 5 bhp from 1st to last at PE, they also fire the water spray (well mervyn does).

Bob

Branners

isnt detonation a very very bad thing, and by the time you get it its really too late and the damage is already done?

One of our Supras had a slight blockage in the fuel filter which caused it to run lean, detonate and lose 2 pistons (minor damage but enough to cause problems and require a rebuild).

Lee

Ah..quattro..already shown him the knocklink..

ben, where's my commission ??

Trout

iTrader: (1)

Sadly, I am more than concious of detting being a VERY, VERY BAD thing - I would prefer 280bhp safely than 325bhp and a blow up.

Car is being driven very carefully at the moment in the rich zone, until it is better - which is hopefully soon.

I don't think the PE set up can be even remotely to blame as other STI Vs and other cars ran fine - also the heat issue would not explain the very low CO readings.

To reflect - I posted this as a lesson learned in terms of looking after your car - many of us CANNOT be sure our cars are truly healthy without this type of test. I knew my car was not quite right in terms of running - but I did not realise how bad it could have been.

Cheers,

David

quattro

David,

I dare say that we CAN both have a nice indication and even know what is or is not happening if certain items which are suddenly pretty well known and coming into appreciation, are installed and used for a good cause. They happen to be called LambdaLink and (in particular for your situation) KnockLink. Simple to fit, inexpensive to acquire and telling a lot. You know who to talk about this more after you already did last Saturday.

Hope to hear your car is well again real soon.

regards
q.

Simon R

Lee / Quattro

Can the Knocklink be fitted to a car with the standard Subaru ECU or do you have to have to Possum fitted?

Simon

firefox

Howdy..

The Knock and Lamba kits are actually standalone units.. that connect into the original standard sensors...

Therefore you can run what ever ECU you wish, and can also run these kits....

Where's my commission Ben/Mike ?

J.

quattro

Of course it can. This is a monitoring device and is suitable for all Imprezas of any origin and vintage. As I have said many times, email Bob R. and a simple to understand but meaningful explanation will follow. The device is very cheap for what it does and invaluable. Do, however, bear in mind, that monitoring is not making it different. Lifting off throttle certainly is a 'removal of symptoms' but not also a remedy. For that you need other things which have also been discussed lately.

q.

Lonnie

Hey Rannoch
If you have toluene (methylbenzine) available in the UK
try adding 10 litres per tankfull of SUL. Usually it
can be purchased at one of the refineries in 20 litre drums.Hopefully this should stop detination if it was fuel quality and you should be able to run
a bit more boost if it's not leaning out.
hope this helps.
Lonnie

firefox

Howdy..

The LambaLink is the same as the others..

They all use the same 3417 (i think) chip... which is a simple voltage (or frequency) to bar graph driver... The circuit only requires about 6 other parts...

Some kits have extra components for filtering and transient supression, etc...

I know of about 5 other makes of the Lamba sensor... some have more LEDS than others (cascade the chips)...

Cheers,

J.

ps - Search the web.. there are no end of websites on EGO monitors.. and how to build them, etc...

Wreckleford

Is the lambda link any different from the millions of other air fuel ratio meters available? It seems like it is being presented here as something unique. If so what advantage does it have?

quattro

Lucky you, Wrekcleford. I was not aware there were 'millions of other' devices of the kind available. In any case, it is not better or worse (the world is not all about better or worse, you know) - it simply offers a visual display of constantly changing air/fuel mixture situation and shows you the air/fuel ratio as well as the CO percentage. Oh, and it is pretty cheap too. So, no miracles this time, I am afraid. If you have followed memebers' input on this subject recently, you will have noticed there are just a VERY few people around who can give you all the 'white paper technical knowledge' you need to have and also some who are eager to sell.

Hope this helps.

q.

Trout

iTrader: (1)

I have a HAPPY CAR!!!

And boy is it annoying.

Did a fuel pressure check today - 3 bar at idle, 4 bar on boost - so not the fuel pump, possibly a blocked filter.

Then I mentioned to my man that I had had problems with my HKS AFR - so he asked me some questions about how it was fitted and what type of connectors were used. He then showed my a knackered piston from a car utilising a repaired wiring loom which was not giving correct voltages - within the envelope, but not within the performance tolerance of the engine it was removed from...

...anyway we opened up the passeger footwell to reconnect the AFM circuit and a I was shown another sensor wire - don't know which one yet - that had been cut and then repaired with a wire bridge - not a single wire bridge - but two bits of wire which were then connected with a crappy pressure joint - you know the type that you clip on.

This was clearly aftermarket - but by whom and when!!!!!!!!

This has been removed, both the AFM circuit and this circuit have been resoldered - and lo and behold the car is running like a dream.

Humppphhhh!

I am taking the offending bit of wire to Park Lane who supplied the car - as for a decent connector I could have lost my engine. If I had run Donington as planned, I would have definately lost the engine.

But, for now, I am happy!

So a big lesson is that any compromise to the wiring circuit may not show up an ECU or sensor fault, but could well be fooling the ECU into doing the WRONG THING.

Don't compromise.

Cheers,

David

Trout

iTrader: (1)

Sorry, forgot to mention that my man is Mark at M.A. Developments - associated with ScoobyMania.

Cheers,

David

robski

Good news!

So, back to PE for a dyno run then!?

robski

DaveU

David - glad to hear the car's OK.
We'll have to put the cars on the rollers before the 'Pod next year.

Dave

PS Just had a completely new Blitz system fitted to replace the ill fitting one i had previously. If you thought that one was loud - wow! This one's a completely different exhaust.
PPS Got my induction kit & octane booster on order now

Trout

iTrader: (1)

Mr U,

we are having another North Hampshire meet soon - see ya there!

David

PS Blitz - spitz - I will have my Possum LINK by then, running 18lbs boost and no fueling problems!