Surge on Stage 1 K04 - Cured

[JamJay]

I don't know enough about VAG-COM to confirm but we're running out of options quickly. The MAP sensor is the only thing that you haven't tried and then it is down to the ECU map surely, like some sort of weird adaptation or perhaps some very obscure and hard to find boost leak

 

[Markypoo]

I dont have any boost leaks so if its not the MAP might have to start looking for restrictions in pipes and intercooler

 

[JamJay]

For those that have enquired here, via PM or otherwise, this is what has turned up...

100% genuine with yet another supercession in the p/n by VAG

I'll be fitting and logging tomorrow.

 

[t0m]

Good stuff! Will check back on this thread tomorrow evening sometime to see if it's worked.

 

[leons_ leon]

Hello m8, the badger 5 tip seems to change the sound on mine 2 and i love it. It does make alot of sound low down, well mine does any way. Logs look good to me, 257 bhp or close to it. What did you make on dyno? I dont think heat soak will be a problem tonight, its freezing here lol.
heres my logs to compare

Sunday	6	March	2011	19:03:02	
1ML 906 032 		1.8l R4/5VT      01 0001			
					
	Group A:	'002			
		RPM	Load	Inj. On Time	Mass Flow
	TIME				
Marker	STAMP	 /min	%	 ms	 g/s
	0	2560	104.5	8.84	53.14
	0.4	2600	107.5	8.84	55.31
	0.8	2680	129.3	11.56	71
	1.2	2800	159.4	14.28	105.81
	1.61	2960	191.7	20.06	144.39
	2.01	3120	191.7	23.12	169.25
	2.42	3320	191.7	24.14	143.56
	2.8	3520	191.7	24.48	175.5
	3.21	3680	191.7	24.48	182.75
	3.73	3920	191.7	23.12	183.44
	4.13	4080	191.7	22.1	185.36
	4.53	4240	191.7	21.76	184.64
	4.93	4400	191.7	21.08	188.69
	5.33	4560	191.7	20.74	196.58
	5.84	4680	191.7	20.4	197.89
	6.24	4840	191.7	20.4	198.42
	6.64	5000	191.7	19.72	201.64
	7.04	5080	191.7	19.72	205.47
	7.44	5200	191.7	19.72	211.75
	7.84	5320	191.7	19.72	218.42
	8.24	5440	191.7	19.72	216.36
	8.65	5560	191.7	19.38	216.67
	9.05	5680	191.7	19.72	220.5
	9.45	5760	191.7	18.36	223.36
	9.85	5840	191.7	18.02	222.28
	10.25	5960	191.7	18.02	223.36
	10.65	6040	191.7	18.02	226.14
	11.07	6120	191.7	18.36	222.28
	11.47	6200	190.2	19.72	222.28
	11.87	6280	185	19.72	221.56
	12.27	6320	175.9	20.4	210.39
	12.67	6400	173.7	19.04	208.33

mine peaks at just over 6000rpm with 226 then slowly comes down, i think this is a sign of heat causing issues as yours peaks later on.

Sorry to spam the thread but how do you do these readings? thanks

 

[sambryant]

you need vagcom and then you run real time logs

 

[leons_ leon]

you need vagcom and then you run real time logs

can it be done with vcds lite?

 

[JamJay]

Hi all.

Right, no new logs as the laptop has broken...again! Anyway, new N75 fitted and the car ran like a bag of cr@p, the surge didn't got away and the car got some massive hesitation issue pulling away and between gear changes at high RPMs and was really sluggish. Old N75 back on, car felt more lively right away but something is still not right.

It was warm yesterday and I think that the car is heat soaking massively, I could feel it struggling to chew up the warm air and the car was holding back. I just took it for a drive in the cold morning temps (7c) and OMG the thing nearly snapped my neck, so brutal.

Based on this then I think it has to be an IC and Map issue surely? The colder temps have proven that this car is still there, it's just hiding from me and I don't honestly think that it can cool itself enough. That coupled with generic mapping when it really should be custom must have sent the car nutty...what do you think?

I am going to hit the laptop with a hammer later and see if I can do a 115/118 log.

 

[wild willy]

Forge big race intercooler or the pro alloy one which i run is really going to improve your setup.

 

[JamJay]

I think i'm going to order the Forge on Monday and then go for Stage 2. If I explain the issues to AMD, they should be able to see what's going on while they dyno it right?

Now, what to do with the N75? Why would a new one screw things up, could it be faulty, send it back?

 

[Mark300zx]

I thought the N75 had to be calibrated, isn't there a screw hole in the top, anti clockwise to increase boost and only very slight movements 10 degrees at a time, did you reset the ecu when you fitted the N75?

 

[JamJay]

Hi Mark,

Yes I reset the ECU after fitting but I assumed that it would be pre-set from the factory?

 

[Mark300zx]

I have read that they are designed to run on several different cars,so I presume they would have different levels of boost, is there is a screw on the top that can be adjusted on your new one?

 

[JamJay]

I assume so, a little allen head one iirc. I wouldn;t want to touch this though without someone confirming if they've had to do this...

 

[Mo Arif]

my n75 is still not here, how long did yours take to get to you?

i hope you get your problems sorted mate, im having some major limp mode issues myself

 

[Harris.]

Interesting what your saying about then new part number N75. I've had similar sounding problems as you for a while now and have replaced quite a few bits but never really got to the bottom of it so have given up for now. I have noticed tho that compering actual an spec I seem to get a boost spike with my new N75 to 22.4psi then it seems to hold about 18psi, it Never did this on the old N75 and the car doesn't feel as good as when I had the old one on. Time to change back over I think. I had just put My problem down to intake temp issues and am going to fit a big Ic next month.

 

[wild willy]

i wouldn't adjust the n75 personally, manufactures know best.

 

[elviscat]

Do you know 100% sure the actuator is ok and set right?

Also your 007 is not sticking!

 

[Markypoo]

Dont try adjusting the N75 Jay you'll mess it up completely or the screw will snap.
Mine still has the surge with a standard N75 (same supplier) and with my J valve, I have a standard one on now just to reduce boost until I find the problem then the J is going back on, I knew you had to try a new N75 but like I said to you it didnt cure my problem I also have a Forge FMIC and still have the surge so I wouldnt waste your money fitting one to find its the same, the quest continues

 

[JamJay]

This is just really annoying me now, the car feels good, then it feels bad, it just can't make its mind up. Before I come on boost I get this massive hesitation, like TCS cuts in and then get full boost and the car feels insane. The thing is, TCS is switched off so what could this be? Not sure if it's linked to the surge but could be a good place to start.

I've said this a few times but actuator is OE, never been touched and it works, shorts of taking it off then there's not much more I can do here nut I've already wasted £££ on new sensors. 007 is fine, dumps pressure fine and is audible via the open cone, I tried the OE valve which I knew wouldn't stick and I still had the problem.

I'm not sure what to do Mark, literally there is nothing else to try other than MAP sensor or ECU map adjustment.