BAM engined mk2 Golf large hesitation after idling

jonny-5

Registered User
Joined
Aug 4, 2012
Messages
7
Reaction score
0
Points
1
Location
NULL
Hi all hopefully you lot can help me with a problem i've had for some time now.

The car is a mk2 Golf with a 2002 BAM engine in it. It runs standard S3 ECU and has alledgedly never been remapped.

Basically when you come to a standstill for even a second or two and then pull away, there is very little power across all throttle positions and the engine produces an odd sort of blowing noise not like a turbo whistle noise though, the unit still makes boost as the DV (Forge 008 with green spring) still does it's thing although sounds different.
After 5-10 seconds of driving using part throttle normal power is resumed and the car takes off, if I leave it at full throttle while it's misbehaving then it never clears all the way to the redline - until I drive part throttle for a while as mentioned.

If I don't let it come to a stand still I can plant the throttle and all hell breaks loose as it should.

Worth mentioning that if say when I'm driving at 50mph and then let it coast in neutral for a while as if I was at stand still and then accelerate again, it again drives normally.

The fault codes I get are 16487 - maf flow too high and 17963 boost upper limit exceeded
I have done some logs before which I think I still have and can post if necessary

I've leak tested many times and changed the MAF, N75, coils and lambda. Engine also has a brand new genuine turbo, forge TIP, FMIC, JBS cast manifold. The N249 has been removed as have the carbon can - utilises catch can, it also has a phenolic inlet gasket.

Sorry for the long post but I know how hard it is to diagnose a problem like this remotely.
 
Do you know what boost you are running. If its higher than stock then you know its remapped.

Maybe the map is going into limp mode for some reason then returning back to what it should be.

I had a similar thing on my dodgy remap, in forth gear with my foot flat, belting down the road, as i lifted the throtte off to change gear, it would hit limp mode and work on actuator pressure. If I carried on driving and changed gears a few times, it would suddenly hit full boost again. Was scary at times with another car in front of me.
 
I had a boost gauge connected for a while and it would fluctuate seemingly randomly. Usually it would peak at 13psi or so - suggesting standard map, other times it would go off the clock - around 20-22psi. As I said it would run well at what ever it decided to boost at!
 
That doesn't sound good.
Best put those logs up and let the pros have a look at it, if they have time.
 
maf sensor too high is a clue.. Connector ok? if so try new Genuine Bosch maf sensor

too much boost from ecu not determining load properly (erratic) will cause havoc.

start with maf
 
I bought a new MAF last week, how do I know if the connector is no good? Or is it obvious? If so where can I get another.

Cheers so far, I do have some logs but they're not the best also they're on my home PC, basically the requested/actual boost do what they like, as does the mass air flow. I should hopefully be getting some better ones done on Friday.
 
New MAF means nothing, I have had more faulty brand new MAF's than I have had shagged used ones haha.
 
Put on a new maf connector and after a few days driving the issue is still there. What groups shall I log?
 
Connector only, maf itself is 2 weeks old and I tried another brand new one 5 months before, I've also tried a known good one from a friends S3. All been genuine by the way
 
I had four genuine MAF's from ECP, all four in a row were faulty. Your symptoms say MAF, your fault codes say MAF as well so it would be a little naive to think you don't need to look at the MAF.
 
Last edited:
Still haven't done any logs yet. But, I unplugged the maf and it runs great, really great. I've tested all the wiring for the maf and all the voltage readings are good, as is the resistance readings back to the ecu, also got a new connector on it. Gunna try an known good maf and put a few miles on it before taking the plunge on a new one. Usually I get them from TPS but might try Audi themselves
 
Guessed they might, TPS it is then. 3rd time lucky then I hope, can't believe 2 genuine ones in a row would be faulty like that though, but 16vklappe says - that's nothing! Anyone know the definite part number I need? It's an 02 plate bam engine
 
Guessed they might, TPS it is then. 3rd time lucky then I hope, can't believe 2 genuine ones in a row would be faulty like that though, but 16vklappe says - that's nothing! Anyone know the definite part number I need? It's an 02 plate bam engine
If your new maf dont fix it, then I'm almost sure it'll be your map. 2 maps not adjusted correctly will give those errors.