david

hi guys,

Some time ago a friend (Mark) who owns a MY98 UK spec had his center section changed to the SS option (he also runs with a SS back box). When he next had his car serviced he mentioned this to the dealer, the dealer then told Mark that he would change some settings during the service using the Select Monitor to 'make the car run/respond better' with the new mods.

What can you change with a Select Monitor???

The reason I ask, is that I have the full SS sytem on my V, and after chatting to several people about a jerkyness in the engine when cold, the common response was that my engine could be running lean (very lean). Can this be changed with the Select Monitor (if so, who knows how to do it for me?) or was the dealer talking rubbish.

If the Select Moitor can't do it, do I have to see BRDevelopments and have to go through the process of checking the lambda readings when cold and fitting a gadget to fix it? This is not preferable, as Bob live miles away and my engine is at operating temperature when I arrive.

Cheers,

Dave

Trout

iTrader: (1)

Dave,

two things here I think.

First of all, if a UK car has been modified it is possible to reset the ECU (this can be done with the SELECT monitor) although it can also be done at home using the Diagnostic Connectors, or simply by disconnecting the battery for a couple of hours.

This will possibly enable the car to run better with the mods as the ECU will adapt to the new conditions (within limits).


With your car, I assume that you mean an Sti V, it is not that simple. If you improve the breathing with a straight through exhaust, or other modifications, you will go beyond the limit of the ECU to adapt. This is particularly a problem on the STi V as it already has a 'lean' area on the ECU map at higher revs. In addition running is exacerbated by the UK running 97RON fuel and not 100-104RON.

Overall, and STI V in this state has an increased probability of detonation or knock occuring, which is damaging to the pistons/engine. If your car is running badly when cold this is not a good sign - however this may well not be det.

So the moral of the story is - if you have modified your STi V/VI then it is better to have the ECUs ability to modify the Fuel/Boost/Ignition improved beyond the standard.

To do this consider Unichip, Link, Motec or a variety of Air Fuel Ratio controllers. All of which will need to be fitted and then 'tuned' to the specific characteristics of your car.

Happy motoring,

R

david

Rannoch,

Thanks for the reply. I hear what your saying about the leaning out of my car, just to give a few more details, yes it's an STi V, I also have a Blitz Induction Cone and I use Octane Booster with 97RON.

I do have a knock link fitted, but (and if someone can provide me the following let me know) I need an extension lead for the knock link display as my phone holder is now in the place where the display went, (I also need a similar extension lead for the lambda link display)

On 97RON my car did knock but only after 7000 rpm with foot firmly on the floor, I have never bothered to investigate the knock after I started using octane booster (about 4 months ago), but maybe I'll re-attach the display (if I can get the leads) for a short blast to see whats what.

More specifically, the jerky engine is only noticable at about 3000rpm when cold (and I mean in the first minute of driving) when I lift off the accelorator, it feels like a VERY slight hesitation. Under load, there are no problems at all, and to be honest, I have no worries about knock in my car during road use. It seems to me that this is only a problem for cars driven to the limits on the track, (this has been a big reason why I have not had my car re-mapped as I do not do track days, although I recognise that all these types of problems can be addressed with a re-map, and if I had 1500 quids burning a hole in my pocket I would probably do it).

Back to the UK spec and the alteration, the dealer specifically said that he 'changed some parameters' with the Select Monitor. I agree that 'changing parameters' does indeed cover a reset, he's just disguising the truth. I was wondering if you could specifically change any parameters (other than a reset) with the Select Montor?

Anyway, if any of the above has enlighted anyone to possible answers then please reply.

Cheers,

Dave

[This message has been edited by david (edited 31 October 2000).]

Blackscooby

Dave,

Dunno if its similar, but my UK94 splutters when cold with a K&N cone filter + De-cat SS system. Doesn't run properly until its got warm.

Its got worse since the weather has turned colder. Hesitates quite badly until nice n warm.

Run on SUL.

Cheers

Mark.

R19KET

Exhaust, and air filter mods won't cause a problem on cruise, or mid boost. The Jecs ECU uses "closed loop lambda" here, and can easily cope.

It's only under WOT, where the stock ECU can't cope with the extra air flow, where you may encounter "leaning out". Under WOT, it changes to "open loop", and onto a map.

Most of the det' that occurs with these mods, is caused by an increase in "overboost", that is common with exhaust/downpipe mods. My STi4 was consistantly hitting 22psi with the same mods.

As for hesitation when cold; I would suggest checking the Lambda sensor. It sounds like the heater is faulty, and the sensor is taking a long time to heat up (by the exhaust gas). You can test this with a Lambda Link. If the sensor is working correctly, you should see led's within a min'.

Alternatively, turn the ignition on (don't start the engine) wait for about 1min, and VERY carefully see if the sensor is hot. If it is, the sensor is ok, and I'm bu*gered if I know, but if it's cold...........

It could also be dirty plugs.

Mark.

Trout

iTrader: (1)

Dave,

without going over old ground - my V with induction kit and HKS Hiper would det on the road with SUL, and even with 3% octane booster still suffered from det due to leaning out.

My only solution was to remap with the LINK, it will cost you under a grand tho'. Unichip is slightly cheaper.

Regarding UK car - AFAIK you cannot change the engine parameters with the SELECT monitor - but hey, I could be wrong - again

Cheers,

R

Trout

iTrader: (1)

PS With a LINK you would be surprised how much more advance you can get (with consequent power increase) by getting better control of fueling with the sort of mods you are talking about

david

OK.....I'm a bit pissed now but still, a few questions....

Heater ? ther is a heater on th elambda sensor? if so, can octane booster damage this? (here lies another thread me thinks!)

dirty plugs? I hope not, changed the at Scoobysport after only 15,000 miles. Again, can octane booster make them dirty?

R19KET - WOT

TSheers...

Dave

R19KET

Dave (Rannoch)

Not disputing V5's detting under load/high revs. Davids problem is at 3k, and only when cold. This also means it will be running cold enrichment (choke) it won't be leaning out due to the mod's. If it was, it would happen all the time.

David,

WOT= wide open throttle.

Yes, the lambda sensor is heated. This fails sometimes, and whilst it will work when the engine/exhaust gas gets hot, it's pretty iffy whilst cold.

Octane booster does leave a residue (Millers is a very pleasant orange colour:0)

It's unlikely to cause a problem though, you'd really have to over do it. I use a bottle per tank, with no problems......for quite a while (don't ask).

Mark.

Trout

iTrader: (1)

Mark,

OK, I know that there is a specific problem with the other David's car - I was merely highlighting a wider issue of Vs and big exhausts/induction kits...

...the moral being reconnect your lambda and knock link

R

pwebb

Dave,

you can't 'change' anything with a select monitor (apart from memory reset which won't help much) - but you can monitor the individual function of each sensor in real-time to check they are all functional - I had a faulty LAMBDA sensor diagnosed in this way so it has its uses - you can also monitor the ECU's response to det (knock) detection to check it sees it and retards ignition accordingly - again easy to see on the Select Monitor.

The behaviour you describe is common on the sti5 - it ONLY happens when the engine is cold and the ECU is in its warm -up routine - I can provoke this in the first minute of driving at about 30 mph in 3rd gear - it disappears immediately if I change up into 4th gear (oddly) and engine runs more smoothly - I don't think you need worry about this at all - just a quirk of the ECU settings. Switching to another ECU is a drastic step to take just to rid yourself of this quirk and I believe that some after -market ECUs have problems maintaining a satisfactory idle anyway - and would require repeated re-mapping for changes in fuel,season etc. You would also possibly have difficulties with warranty/insurance.

It would be a good idea to reconnect the knocklink -for peace of mind if nothing else - how about getting the LEDs poked through into the instrument panel for a much neater appearance than the horrid plastic boxes that it comes with ????

regards,

Paul W

david

Paul,

Thanks for the reply, I think I agree with you, mine also dissapears if I change into fourth gear.

I am thinking of putting the knock link display in the instrument surround (the plastic bit in the hole where the rev counter is) but I don't know how to get this but of plastic out, and also, I've heard it's a pig of a job!! I'll have to get a new Knock link module fisrt though as I've broken mine! DOH!! I think I will get round to doing this to have it placed with easy visability.

Cheers,

Dave

Trout

iTrader: (1)

Just out of interest, replacing your ECU may have little or no infleunce on your insurance.

I pay nothing for my Link ECU, although I do pay for other mods. The rationale, as it IS declared, is that the LINK enables me to run the car on UK fuel, which is true. This is also true for a number of others.

It is also useful to do a before and after power run, just be careful which dyno you choose for each run and you will 'demonstrate' a reduction in power with the new ECU

You will, as pwebb suggests, compromise your warranty, but there again your engine is much less likely to melt down.

Regarding idle and mapping - late LINKs have inlet air temperature compensation - get the map spot on and you will be fine unless you are off to Tromso. Same for Unichip which uses the JECS temperature compensation, and for MoTEC.

For idling the LINK is not a smooth as the JECS, but is absolutely no problem to live with, Unichip uses the JECS idle routines, MoTEC is a pain but will be set up by your tuner which is a one-off exercise.

Cheers,

R