Detonation
- Thread starter jaskin
- Start date
Hmmm.... Actually, is there any relation if the car has been kept for quite awhile before its sold off? I've noticed a couple of funny stuff coming from my car but I thought I would just brush it off.
1.) The rev drops and moves up again during mild acceleration. Especially around the 2500rpm. On the rev meter, it shows a slight dip when it hovers around the 2500rpm before moving up again. Dip is mild, about say 50-100rpm?
2.) There's also this sound coming from the rear whenever I move off from a standstill or extremely slow speed. Sounded like I had a sticker stuck on my tyre. The "piak piak" sound.
3.) Whenever I E-brake (but not to a complete stop) and try to accelerate off again. There's this slight delay, I can hear the engine revving but car ai'nt moving. After which the car seems to surge forward a little. Not like a turbo surge but you those type of feeling when you are half clutching too much and then suddenly you throw the clutch.
4.) The suede lining on the doorframe is falling off.... I.E. think the glue's worn out. Damn heart pain, look like some 20 year old corolla with bits falling off....
Well my question is this. Are the above normal cases? If so, do they happen to a car that's about 4 months old?
1.) The rev drops and moves up again during mild acceleration. Especially around the 2500rpm. On the rev meter, it shows a slight dip when it hovers around the 2500rpm before moving up again. Dip is mild, about say 50-100rpm?
2.) There's also this sound coming from the rear whenever I move off from a standstill or extremely slow speed. Sounded like I had a sticker stuck on my tyre. The "piak piak" sound.
3.) Whenever I E-brake (but not to a complete stop) and try to accelerate off again. There's this slight delay, I can hear the engine revving but car ai'nt moving. After which the car seems to surge forward a little. Not like a turbo surge but you those type of feeling when you are half clutching too much and then suddenly you throw the clutch.
4.) The suede lining on the doorframe is falling off.... I.E. think the glue's worn out. Damn heart pain, look like some 20 year old corolla with bits falling off....
Well my question is this. Are the above normal cases? If so, do they happen to a car that's about 4 months old?
Racebred
Core Group Members
hard to ascertain if it's just a characteristic of the car or there's something wrong. need to test drive to find out.
pls bring your 330 to our usual skid pan for further testing. hahahah
but seriously, why dont you try someone else's 330 to see if you can replicate the things you mentioned.
pls bring your 330 to our usual skid pan for further testing. hahahah
but seriously, why dont you try someone else's 330 to see if you can replicate the things you mentioned.
piggyboyz
Core Group Members
Hi there,
Is ur car re-programmed ? Cos i know that a lot of time, the tuner push it too far and result in the detonation...
My previous car has got that problem as well and it will come to a time when even i put back the stock programme, it dosen't help...
The detonation is especially pronounced on the M50 and the M52 engine, esp the 2.0L ones cos they are running much higher compression than the 3.0L engine.. So on hot days, or after a lot of mileage, u will tends to hear them esp in a quiet street or concrete wall area..
But then, don mistaken this sound with the fuel rail, which also produce similiar ticking noise... The detonation one will sounds more like the older days car when the tappet needs attention....
Is ur car re-programmed ? Cos i know that a lot of time, the tuner push it too far and result in the detonation...
My previous car has got that problem as well and it will come to a time when even i put back the stock programme, it dosen't help...
The detonation is especially pronounced on the M50 and the M52 engine, esp the 2.0L ones cos they are running much higher compression than the 3.0L engine.. So on hot days, or after a lot of mileage, u will tends to hear them esp in a quiet street or concrete wall area..
But then, don mistaken this sound with the fuel rail, which also produce similiar ticking noise... The detonation one will sounds more like the older days car when the tappet needs attention....
piggyboyz
Core Group Members
If the car is completely stock, then check if everything is ok...
All else fail, send back to PML to do a diagnoistic check, they might just reload the software again...
I'm sure the stock programme will not cause detonation or it might just be the fuel rail noise..
Aftermarket ECU re-programming might not ba a good idea, most of the time, aftermarket tuner do not do as much R&D as BMW so what they usually does is to advance the ignition timing a lot and rely on the engine knock sensor to pick it up to retard the timing as they always say the knock sensor is damn intelligent BUT in long run, ur knock sensor is always working and the day it wears out, detonation will occur and usually, to the point when u actually hears it, it's quite bad liao...
The stock map is probably one of the most competent one, taking care of both power and economy so unless u have got some mod like cams or a stroker kit, i don see why u should remap the car....
My 2 cents
All else fail, send back to PML to do a diagnoistic check, they might just reload the software again...
I'm sure the stock programme will not cause detonation or it might just be the fuel rail noise..
Aftermarket ECU re-programming might not ba a good idea, most of the time, aftermarket tuner do not do as much R&D as BMW so what they usually does is to advance the ignition timing a lot and rely on the engine knock sensor to pick it up to retard the timing as they always say the knock sensor is damn intelligent BUT in long run, ur knock sensor is always working and the day it wears out, detonation will occur and usually, to the point when u actually hears it, it's quite bad liao...
The stock map is probably one of the most competent one, taking care of both power and economy so unless u have got some mod like cams or a stroker kit, i don see why u should remap the car....
My 2 cents
Racebred
Core Group Members
not much use for him to stroke up like 200cc from his 3.0L block.
i guess if you want to do it the NA way, go check out rennsport and see their NA tune program for the 3.0L. i didnt really go read the details, but i'm thinking it can go 270-280bhp for a stage 2 or 3.
you should be doing things like intake, exhaust, underdrive pulley, ECU mapping, cams. it'll cost as much as a complete SC kit, so i guess you might as well go SC.
i guess if you want to do it the NA way, go check out rennsport and see their NA tune program for the 3.0L. i didnt really go read the details, but i'm thinking it can go 270-280bhp for a stage 2 or 3.
you should be doing things like intake, exhaust, underdrive pulley, ECU mapping, cams. it'll cost as much as a complete SC kit, so i guess you might as well go SC.
yendor
Well-Known Member
IMO, the detonation can come from a couple of ways, some of them include the following:
1. Usage of lower grade petrol. Personally, I have experienced cars with detonation problems coming into the workshop to dyno their cars. During pulling, the engine detinates like mad and the very first question is what pertol are you using. The reply usually come back " I use the (clam) brand cos it gives me better milage" Frankly, I have found this type of petrol to be really more economical (better milage) but at the expense of poorer performance (lower dyno figures cos need to retard ignition.
2. Older engines with a lot of carbon build up on the intakes and injectors. The injectors clog up a lottle and hence sprays less fuel into the chamber and hence engine runs a little leaner. When leaner temps rise and the little edges in the combustion chamber become hot spots that pre-ignite the mixture.
3. Tuners increase ignition advance to try to give best bang for buck. Usually I find that from the original ignition mapping from factory, I can only advance about max 5 degrees no more unless the engine has been well worked over.
Food for thought.
1. Usage of lower grade petrol. Personally, I have experienced cars with detonation problems coming into the workshop to dyno their cars. During pulling, the engine detinates like mad and the very first question is what pertol are you using. The reply usually come back " I use the (clam) brand cos it gives me better milage" Frankly, I have found this type of petrol to be really more economical (better milage) but at the expense of poorer performance (lower dyno figures cos need to retard ignition.
2. Older engines with a lot of carbon build up on the intakes and injectors. The injectors clog up a lottle and hence sprays less fuel into the chamber and hence engine runs a little leaner. When leaner temps rise and the little edges in the combustion chamber become hot spots that pre-ignite the mixture.
3. Tuners increase ignition advance to try to give best bang for buck. Usually I find that from the original ignition mapping from factory, I can only advance about max 5 degrees no more unless the engine has been well worked over.
Food for thought.
