Gridlock Mikey

Please read this with an open mind, it's important that you realise that if i said this to you in a pub or at a meet, it would not be said in a agressive, arrogant manner more in a quizzical term. The same way as some of my mates ask why I have a Scoob. They don't want a fight, they are just interested as to what makes me tick So a few deep ones and see how you get on.

So your out for a spirited drive one Sunday afternoon, window down, all is well, you approach a tight bend, you set the car up, brake, turn in, and power on out of the corner We've all done it and it's one of lifes true pleasures

Now imagine the scene as above except, set the car up, turn in, and stare at the gauges, monitors, sensors etc sweating
Hoping that one of many combinations of lights does not appear!

I'm not having a go

But let's say the Knock Link shows detting, what do you do, lift off and crawl home? Then what? How do you sort it out on a Sunday afternoon? Do you then have to run the car almost dry and hope the next batch of fuel is better? Add OB? Call someone out? Not drive it at all until someone has been out to check it? What do you do?
Ok so you know the car isn't right and it's NOT wrong to be aware of the fact, but what can you do about it once your gauges have prevented an expensive engine rebuild? Sit at home sipping a beer thinking " well me car's sort of knackered but at least the engine is still in one piece!"

I figure that if you are a ECU programmer with a lap top and the knowledge, then you can sort it out. If like me, you wouldn't know where to start to advance/retard ignition timing etc, wouldn't it spoil ya Sunday?

Just wondered and please don't give me too much of a hard time, I did learn from the last time honest

This is just me personally, i'd rather enjoy what my car does for me and not worry too much about how it's doing it. By the way, just to redress the balance sometimes I "think" that something is not right with my car and i think "hope that's not x,y,z" If I had the gear, i'd know. On every occasion though, the "problem" has gone away, probably because i've forgotten about it or i've found some change rattling in my gear gaiter

Mikey

Tim Bomford

Do you have a new ecu or the std one the car came with?

If its remappable like Link, MoTeC etc then get a re-map done to be safer.

If it isn't then consider a re-mappable ecu!

It could be down to crap fuel simply. Could try running booster?

I wouldn't drive the car quite as hard and try to avoid the knock until you are in a position to do something permanent about it. I would not put it back in the garage and not use it though.....

Any use??

Tim

Gridlock Mikey

Absolutley Tim, thanks.

I thought detting was terminal in every case if NOT treated sympathetically within 0.00007secs

So do you get varying degrees of det and does it tend to just happen when you are hoofing it, say above 6000 rpm?

Mikey

Fat Boy

You lift off as maybe you've just put a batch of bad fuel in, or it could be something as simple as weather conditions or something like the Maf beginning to fail and leaning out the engine. Either way it tells you to lift the pedal and investigate why you're getting knock.

Quickest solution is to put some more OB in, but you won't know to do that if you can't hear or see evidence of det.

None of the above will spoil your Sunday afternoon quite as much as the engine going bang, of course.

Most det seems to happen on wide open throttle at mid to higher revs - but a scooby can still scoot along pretty quickly at 3/4 throttle and lower revs until you use up the crap fuel or weather conditions change for the better.

Gridlock Mikey

That's cleared that up then

It's sooooo easy to read the "det" threads and think that the end of everything scooby would happen if det is present and very quickly at that I thought that if knock was detected you had to near as damn it stop and "woe betide anyone" who carried on driving.

Balanced views and opinions, I love Scooby net

Mikey still happy with his boost gauge and that's it

john banks

Det is destructive in the extreme, the problem is that det is not like a giant red kangaroo hopping up to your car and knocking on your window but rather more subtle, so a lot of damage can be done without realising it.

I just position the knocklink so that if the obvious big red light flashes I will notice. Then I just get on and drive.

For a consumer map the knocklink should be pretty quiet, and a big red light would be quite obvious. If it is suddenly detting all over the place then something has changed significantly to make it do so:

Leaks
Poor octane
Very harsh conditions
Overboost
Fuel system compromise
MAF sensor or other sensor failure

Mapping for a consumer car generally takes account of a large safety margin (as do the ECUs abilities to some extent) to control day to day variations that are more subtle.

A hot track day on 95 RON with overboost on a small turbo with a TMIC with an on edge map will obviously be rather different to Optimax plus booster on a large turbo at low boost with a FMIC on a cold day with a quick burst of overtaking from a 50mph cruise