uneven power delivery

[ametlib]

Take a run in third from low rews and all the way up and look at the boost with VCDS in graphs, check if actual follow requested, if you see anything suspect, start by checking the vacuum pipes and especially the T connectors besides the fuel filter

[Mark Davies]

I'm a little unsure about logging

Just to confirm
I just use 'vc scope' and monitor 'Maf specified' versus 'Maf actual'

I'm not sure how to show boost, do I measure certain blocks?

Should I put anything else on that graph?

[ametlib]

Boost is in Measuring blocks 11 , just take a short run to check if the turbo performs. Another thing ,when you hook up VCDS anyway, when engine is still cold, check the temp values , in MB 7 I think, they should all 4 be showing pretty much the same values

[Mark Davies]

Hi

I did a run, 3rd gear and uphill, and put it into http://vcviewer.com/
chart.jpg



log data also here

Tuesday	25	August	2015	20:37:01:60804	VCDS Version: Release 10.6.0
8E0 907 401 M		2.5l/4VTEDC G000AG 0004
	Group A:	'011
		Engine speed	Spec. intake press.	Actual intake press	N75 duty cycle
	TIME	2900-4000	1900-2300 mbar	1900-2300 mbar
Marker	STAMP	/min	mbar	mbar	%
	0.01	1322	1785	1122	85.2
	0.3	1346	2009.4	1254.6	85.2
	0.64	1392	2019.6	1315.8	85.2
	0.99	1438	2019.6	1387.2	85.2
	1.34	1485	2029.8	1448.4	85.2
	1.69	1554	2040	1519.8	85.2
	2.05	1601	2060.4	1601.4	85.2
	2.41	1670	2070.6	1703.4	78.5
	2.77	1740	2080.8	1825.8	73.8
	3.13	1833	2091	1938	69.4
	3.48	1902	2111.4	2050.2	61.5
	3.85	1972	2111.4	2162.4	57.2
	4.21	2065	2111.4	2244	52.9
	4.56	2158	2111.4	2274.6	50.9
	4.92	2227	2111.4	2315.4	46.9
	5.29	2320	2121.6	2366.4	43
	5.61	2390	2131.8	2397	40.6
	5.92	2459	2142	2325.6	47.3
	6.23	2529	2142	2091	57.2
	6.57	2552	2152.2	1978.8	57.6
	6.92	2598	2152.2	1948.2	58.4
	7.29	2668	2162.4	1958.4	58.4
	7.68	2714	2162.4	1989	58
	8.03	2714	2162.4	2019.6	58.4
	8.4	2761	2172.6	2050.2	60
	8.75	2807	2172.6	2080.8	60.4
	9.11	2830	2182.8	2101.2	61.9
	9.47	2900	2182.8	2131.8	61.9
	9.83	2923	2182.8	2162.4	61.2
	10.14	2970	2193	2182.8	60.8
	10.51	3016	2193	2213.4	60
	10.87	3062	2193	2223.6	57.6
	11.23	3086	2203.2	2254.2	55.2
	11.6	3132	2203.2	2264.4	54.1
	11.95	3155	2203.2	2274.6	51.7
	12.34	3202	2203.2	2284.8	47.7
	12.73	3225	2203.2	2274.6	46.6
	13.08	3271	2213.4	2244	45.8
	13.45	3318	2213.4	2223.6	46.9
	13.8	3364	2213.4	2203.2	47.7
	14.16	3410	2213.4	2193	48.5
	14.56	3434	2223.6	2182.8	48.9
	14.92	3457	2223.6	2182.8	49.7
	15.28	3480	2223.6	2172.6	51.3
	15.64	3526	2223.6	2193	51.3
	16	3573	2223.6	2193	51.7
	16.39	3596	2223.6	2203.2	52.5
	16.78	3619	2223.6	2213.4	52.5
	17.15	3642	2223.6	2203.2	52.9
	17.52	3689	2223.6	2213.4	52.9
	17.88	3735	2223.6	2213.4	53.3
	18.24	3758	2223.6	2213.4	53.7
	18.64	3782	2223.6	2223.6	52.9
	19.01	3828	2223.6	2223.6	52.5
	19.38	3851	2223.6	2223.6	52.9
	19.74	3851	2029.8	2223.6	59.6
	20.09	3666	1662.6	1774.8	52.5
	20.45	3689	1560.6	1489.2	72.2
	20.83	3573	1540.2	1591.2	58.8
	21.22	3526	1530	1642.2	53.7
	21.6	3410	1509.6	1632	51.7
	21.97	3318	1489.2	1601.4	61.2
	22.33	3178	1458.6	1570.8	62.3

[ametlib]

A bit of turbo lag from start, pretty normal, I guess a new N75 wouldn't make things worse. Away from that, if you have low power in the top end, the turbo is not to blaim, must be something else.
Could be the CTS or something more exiting like missing valve rockers or partly clogged up cathalysts or clogged up pick up in the tank or something else