JjCoDeX75

Hi guys

As some may know I recently suffered from DET issues with my shonky ford, and managed to resolve by taking the car to the legends that are MSD.

Happy to say that they did a top job, and det went bye bye!

Sad to say that Det has taken a recent re-visit to planet cosworth. Quite frustrating really, and quite sure that it has nothing to do with the ECU.

I had a guy follow me whilst gunning it to see if there was any external evidence of the issue. It was noted that the exhaust popped a little 'white' smoke cloud which coincides with the det sounds.

To my mind, white smoke would be water. Whilst there is no obvious evidence of Head Gasket failure, I cant help wondering if what is happening is that a small amount of water if killing the fuel during high boost situations and causing the det.

Any thoughts on this?

JJ

rapidcossie

head gasket starting to go.

only making its self evident under high load.

does it use water?

what did stu think it was?

maybe worth doing a leakage test?

JjCoDeX75

I would have said no - at least I have not had to top her up yet. To be honest, the det only occurs in fourth and fifth under full load (just after peak torque).

Last time the gasket failed, it went very gradually and only seemed to breach under extreme boost. It is beginning to feel rather familiar.

Bugger. So is my thoughts on the little puff of white smoke right then, do you reckon Euan?

JJ

rapidcossie

Im no expert mate but what you say makes sense.
what did Stu do to cure it?

JjCoDeX75

Stu live mapped it - it was running too lean originally which was leading to the det. I have every confidence that the map is correct, as when I drove her away - she was det free. Maps dont just undo themselves, which leads me to believe that this is a separate issue with similar symptoms.

Before I rip the head off, I am gonna borrow a wideband lambda and also check the fuelling to make sure something hasnt gone adrift on this side of things.

I am mindful that I am only using a Gp A headgasket (as an experiment to be honest), so I wasnt expecting great things.

JJ

rapidcossie

can you hear it detting as you drive it?

could be something like a failing fuel pump? dodgy fuel press reg?

JjCoDeX75

Hi matey

Yup - you can actually hear here doing it - but it is more like the sound of sparking rather than typical pinking - but pretty unmistakable to my mind.

Both Pump and Fuel Press reg are new, but this doesnt rule them out as being dodgy mind! I will be checking both to make sure!!!

JJ

rapidcossie

if you can hear the det while driving its VERY bad.

Is the fuel filter new?

really needs checked again.

Why not get it on a rolling road where you can have your head inches away from the engine and diagnose the prob alot easier than driving it on the road?

JjCoDeX75

Hi mate - yes Filter is reasonably new. The det issue is very very familiar to me - I suffered with it for quite a while before Stu solved it with the map. It is not the usual sound that is associated with det (ie traditional pinking) - it is hard to describe. The car runs exceptionally well - which is not consistent with a car that is detting its tits off. I can only assume that the problem is localised to a single cylinder, and in very specific conditions. Either that or I have super human hearing (which I dont!)


I have a friend with a rolling road. I may have a play with his at the same time, though in my experience, the ambient noise usually ruins the gains.

I agree with you about ruling out poor fuelling - this should be easy to eliminate though - I will put the reliable Wideband Lambda on it once I have corroborated the figures for the pressure regulator (again this should rule out the filter if it is blocked then it will not allow the regulator to see the requisite fuelling), I will run her to see what the air fuel ratio is. If it goes a little to lean, then I will have my answer I guess.

rapidcossie

Its a hard one mate.

Does it sound more like single sharp cracks rather than the normal tinkling sound of pinking?

JjCoDeX75

Yes - that is quite a good definition really! Mean anything to you?

JJ

JjCoDeX75

Bump cos my problems are more important than everyone elses ROFL!

JJ

Chip

iTrader: (3)

Get the wideband on it, no point guessing till you have done that.

Fingers crossed its a terminal failure

Jamz

That's not very nice

Chip

iTrader: (3)

Im passenger with JJ to go to the ring in a few weeks.

If the cossie is fucked before then, it means we go in his M5, which would you prefer to spend a long weekend in?

JjCoDeX75

If you're not careful, Ill take the Daewoo!!!

JJ

Chip

iTrader: (3)

That would be comedy gold in fairness though

JjCoDeX75

ROFL - we would need a fair amount of Power Steering Fluid mind!

JJ

Chip

iTrader: (3)

Nah, you dont need PAS at the ring

Deleted by Request

...was it mapped to the edge?...Some tuners do others dont..the ones that do normally suffer failure if driven flat out....as a slight change in many factors brings the det on.

JjCoDeX75

I know, but the pump whines like a bitch when its dry ROFL!

JJ

Chip

iTrader: (3)

Fit a shorter belt that just goes to the alternator then.

* Edit - Why are we even discussing how to take the daewoo? we'd be better off in my a4 tdi than that FFs

JjCoDeX75

I think that is probably true, Phil. As you say - now the car is mapped properly, if something small changes the it could cause the issue. From my basic knowledge of tuning, the best power is achieved just before det, so that would makes sense

JJ

Chip

iTrader: (3)

Typical safety margin for most mappers is about 3 degrees.

Manufacturers do it properly and run least required advance, but its impossible to do that on a live map on the road.

JjCoDeX75

So in english, are you saying you agree or disagree?

JJ

Chip

iTrader: (3)

Im saying that a standard car will have a bigger safety margin.

But 3 degrees should be plenty for any minor change to not cause det.

So kind of neither agreeing or disagreeing totally.

rapidcossie

the single cracks are the start of proper det and not just the normal pinking that you get under load in alot of NA cars.

Thsi is the stuff that melts pistons mate so be careful.

I would stop testing it on the road yourself as you are probably damaging the engine.

On another note my old engine used to make good power fo rthe spec and had a good mixture but detted its tits off due to an oil burning issue. It was contaminatin g the mixture under high loads.

Sounds similar to your probs mate...

JjCoDeX75

You could be right, though to be fair it has smoked more than she does at the mo!! I will check fuel, then rip the head off. No melted pistons for me please!

JJ

rapidcossie

could be a dodgy injector?

if you are running too close to max duty cycle one could be sticking open?

JjCoDeX75

Hmmm - I hadnt thought of an injector issue - the trouble with this is that this will be pissin hard to diagnose. Again - the rollers may help on this

JJ

rapidcossie

flow test injectors

JjCoDeX75

Yup - that could be sensible!!! ROFL!

JJ

rapidcossie

I would aviod ripping the head off until all other areas have been exhausted.

could be something like ACT's building inthe high gears causing your det?

Have you measured them?

JjCoDeX75

I have the RP Labs software. I must admit I havent checked it recently, but I have never historically had an issue with ACTs (last checked I guess about a month ago).

What sort of things can lead to elevated ACTs?

JJ

rapidcossie

Can you data log on the software?

maybe worth doing a few runs to see what happens?

cossie4i+

iTrader: (15)

Not more problems James

Hope you sort it

Steve.

JjCoDeX75

Yup, I can data log - that is what I will do.

Hi Steve- yup - it wouldnt be my cos if it was trouble free

JJ