Urgent Help Needed (Quickly)

[Ænema]

Had my car remapped last week, and have had problems with Limp mode ever since. I've changed N75, cleaned MAF, serviced DV and checked for boost leaks. I've got the guy who mapped the car with me at the moment, and we've done a log with VAGCOM. Can someone look at the boost pressures below and let me know what they think. From what I can tell... it's running FAR too much boost!!!

Group C:	'115			
	Engine Speed	Engine Load	Charge Pressure	Charge Pressure
TIME	Engine Speed		(specified Value)	(actual Value)
STAMP	 /min	 %	 mbar	 mbar
87.25	1400	41.4	1010	1030
88.15	1480	76.7	1770	1060
89.05	1720	91	2030	1220
89.96	2000	100.8	2200	1370
90.87	2360	119.5	2240	1650
91.77	2760	154.1	2300	2080
92.68	3240	168.4	2280	2350
93.58	3720	169.2	2260	2290
94.49	4200	165.4	2290	2250
95.39	4640	163.2	2250	2160
96.3	5040	160.2	2220	2100
97.2	5400	155.6	2240	2000
98.11	5720	148.9	2250	1920
99.02	6000	142.1	2230	1860
99.93	6240	138.3	2270	1830
100.83	6480	132.3	2300	1810
101.73	5160	11.3	1010	1110
102.63	4040	12.8	1010	1060

 

[Ænema]

Peak mbar reading is 2250 (actual not specified) which (if converted correctly) is 32psi!?!?

And before anyone asks... I've done a search, but whilst I'm still looking if someone with the know can answer this quickly it'd be much appreciated... and well worth a beer token!!!

 

[LEE69]

IIRC you remove 1000 mbar and it makes it about 18 psi

 

[Ænema]

IIRC you remove 1000 mbar and it makes it about 18 psi

So vagcom starts @ 1000mb, therefore you need to take readings -1000mb to get accurate reading? Makes sense when at 1400rpm it's running 15psi... take off the 1000mb and its 0.4. Makes a lot more sense!

Results in better format, and also showing G/S from MAF reading.

RPM	 g/s		RPM	Specified PSI	Actual PSI
1400	9.7		1400	0.1	0.4
1560	25.8		1480	11.2	0.9
1800	32.7		1720	14.9	3.2
2120	47.2		2000	17.4	5.4
2480	69.0		2360	18.0	9.4
2880	97.8		2760	18.9	15.7
3400	120.7		3240	18.6	19.6
3920	128.6		3720	18.3	18.7
4360	137.4		4200	18.7	18.1
4760	149.9		4640	18.1	16.8
5160	157.2		5040	17.7	16.0
5480	159.7		5400	18.0	14.5
5800	161.8		5720	18.1	13.3
6080	163.6		6000	17.8	12.5
6360	164.9		6240	18.4	12.0
6160	29.8		6480	18.9	11.7
4800	13.7		5160	0.1	1.6
3680	6.9		4040	0.1	0.9

 

[N1njaboy]

My stage 1 is running near enough identical figures to yours if thats any help

 

[james.l]

Have you checked for fault codes?

 

[Chris4877]

Is it not the coil pack

 

[ben450]

Who mapped it?

 

[Ænema]

I've checked for fault codes, and it came up with check boost pressure between turbo and DV (check DV). I think this was from before I changed to a yellow spring, which I've now done.
It also came up with an error for the MAF... something about hte signal being too weak... but I'd had this disconnected to test.

He's cleared all the fault codes off, and is coming back tomorrow with a stock map file to put it back to standard to see if there is anything actually wrong wth the car, then he's going to try a modified map file.

Glad the figures look pretty similar to others out there.

It's been done by a company called "Super Tuning"... mobile car mapping in the north east. He get's his files from a company called Alien Tech I believe. He's been endlessly helpful and supportive so far... so hoping the service continues until we bottom this out.

I am going to try running it without the MAF again though as it's running lumpy on Idle (buy only intermittently). So, I'll disconnect it and see if I continue to get limp mode or not!

Thanks for the help guys... I've found odds and sods knocking about, but might be worth someone putting a sticky together showing standard g/s and PSI/mbar and then typical results with a stage 1 map... just for noobies like me to quickly refer to without having to spend hours searching multiple threads for multiple answers and havng to ask questions which I'm sure most of you are fed up of answering.

I've seen the 1.8T Troubleshooting guide... and that's spot on... helped me identify which blocks to log on VAGCOM

 

[Chris4877]

When your driving it is your engine management light flashing when you accelerate

 

[N1njaboy]

As you have access to vagcom it might be worth doing a throttle body allignment aswell.

 

[Muttley]

1 bar (or 1000 millibars if you prefer the tautology) is 1 atmosphere, the air pressure at sea level. So anything above 1bar is boost, anything below is, well, suck.

VCDS is reading the absolute pressure in the inlet manifold, from the MAP sensor.

 

[Ænema]

Right... just been out to give the car a bloody good ragging, BUT I first disconnected the MAF (again).
Took it out, waited for it to get up to temp and took it right through the rev range in 2nd, 3rd and 4th, then held her steady at 3500-4000 rpm in 5th and 6th. Boosted well, NO LIMP MODE.

But the g/s readings on the logs I did were OK? (were they). If so, why would the MAF be causing limp mode if it's connected. I'll be buying another one tomorrow anyway, because it's clearly the root cause of the problem.

As I mentioned above (I think), the car has been a little iffy on Idle as of late... but not all the time. Revs drop down to about 600rpm and feels like it going to stall... but I cleaned the sensor with some Isopropyl alcohol (as advised) and the idling now seems fine.

Could the MAF still be the problem, even though my Idle is fine and the g/s readings seem OK? Saying that, on those readings, the car wasn't in Limp Mode.

 

[Ænema]

When your driving it is your engine management light flashing when you accelerate

No, but the EML did come on after having the MAF disconnected for a while. I am assuming that is normal?

 

[Chris4877]

No, but the EML did come on after having the MAF disconnected for a while. I am assuming that is normal?

Yeah thats normal when you unplug the MAF, reason I ask about the coil packs is it's normal for them to go when you have a remap, happened to me, sluggish and felt like it was going to stall. When I had my map done though I wad told my MAF was knackard although I had and still have no problems with my car. It was done at awesomegti so i know it's broke but like I said, no issues

 

[LEE69]

Don't rag the car with the maf diisconnected.
My coils never blew with either of my maps.

 

[Chris4877]

Don't rag the car with the maf diisconnected.
My coils never blew with either of my maps.

Might just be an LCR problem, just cos my MAF is broke but I'm having no problems

 

[LEE69]

NAh they blow on either just mine never did after the magical coil blowing maps lol

 

[Ænema]

Right... well after disconnecting the MAF and having no problems with Limp Mode... I bought a new MAF (bosch) and fitted it. Car runs fine, but still getting Limp mode!!! How come it doesn't happen with it disconnected, but it does happen with a brand new one that has no problems connected?

Argh! I'm at my wits end now! I'm going to have to put the car back to standard... but it'll mean I'll have spent £285 on the car and for nothing (bought yellow spring, MAF (not bosch) that can't be returned, MAF (bosch), N75 valve and I'll lose £75 from the tuning guy because he won't give me a full refund. **** Sake!!!

Any help would be appreciated.

Why the hell would it work fine with no MAF, but go into limp mode with one connected?

 

[mty12345]

Have you still got the "check boost pressure between turbo and DV (check DV)." fault code? If that is the fault with the code number 17705. Then that can be a split pipe underneath the manifold. I had it coming up a while ago and it used to go into limp-mode now and again because of it too. Replaced the pipe, no more limp-mode or annoying "17705 (check dv)" code. Worth a look because i might be wrong but i would imagine that if the MAF was disconnected then it might stop that code (and hence limp-mode) being thrown because without the MAF then the engine isn't going to be sure of the exact airflow so won't be able to detect the 17705 "boost leak"? Definitely worth checking IMO