A5 8 speed turbo lag/high rpm for boost?

My one gripe I have with a5 is how poor the initial throttle response is, when compared to my old VW CC, and even my mother’s Tiguan 2.0t. I find this car can’t really hit boost until 2200-2500, and it is very laggy unless if the transmission downshifts. It pulls hard once it gets going. My vws will hit boost very quickly if I lug it below 2k and stab the throttle. I’m just wondering if this is normal for the 8 speed or b8s in general? I recently did a walnut blast, replaced plugs, pcv valve, and the DV has already been replaced with the piston type unit. I have vcds so what are some things I can log or tweak?

I don’t have an A5 but see if you get feedback from other owners or do a Internet search and see what they say about Boost onset. With that said, on a stock Turbo, freeing up the exhaust is the best way of getting the Turbo to spool up a couple hundred RPM’s earlier: Cat delete, downpipe, etc…

You might be getting a ECU controlled boost lag due to the fact that the A5 isn’t really meant to be a sport or sport feeling accleration sedan.

Also to back up hahnmgh said. The exhaust will help free up some performance if it’s getting capped.

I have a p0420 code which isn’t turning on the cel, and I don’t seem to have any exhaust leaks, so I suppose my cat could be on its way out and robbing some power. I’ve wondered if the turbo is worn but I hardly have any oil consumption

To test your MAF, O2 sensors and catalytic converter, check out the following blocks in the “Engine” control module with your VAG-COM. Blocks 002, 030, 032 and 033 are done in “Measuring Blocks” while blocks 036, 034 and 046 are done in “Basic Settings”.

Block 002 - Load Registration

  • Check the MAF airflow reading at idle. Make sure the car is running and warmed up and the A/C is off. Go to Block 002 and look in Field 4. The value at idle should be between 1 and 25 g/s. If it’s lower than 1 g/s, then there is probably a leak in the intake tubing between the MAF and manifold.

Block 030 - Oxygen Sensor Regulation

  • Go to Block 030. Field 1 is a three-digit binary code which gives the status of the pre-cat oxygen sensor. Field 2 is the same thing but for the post-cat oxygen sensor. The digits indicate whether or not the sensor heater is working and whether or not the oxygen sensor control is operational and active. The value should fluctuate between 111 (heater on) and 011 (heater off). The last two digits can also fluctuate between ‘1’ and ‘0’, but should be predominantly ‘1’.

Block 032 - Oxygen Sensor Control Learned Values

  • Go to Block 032. Field 1 represents the fuel trim at idle (additive) and Field 2 represents the fuel trim at part load (multiplicative), i.e., while driving. The value should be between -10 and +10% (negative indicates the engine is running rich and positive indicates the engine is running lean). If the value is close to +25% (which is the upper limit), it usually means that the MAF is bad. If the value is somewhere betweeen +10 and +25%, it could mean that the pre-cat oxygen sensor is bad, there is a leak in the intake or that the MAF is on it’s way out.

Block 033 - Pre-Cat Oxygen Sensor Control

  • Go to Block 033. The value in Field 1 represents the pre-cat oxygen sensor control. The value should fluctuate at least 2% in the -10 to +10% range.

Block 036 - Post-Cat Oxygen Sensor Control

  • Go to Block 036 (this test must be done in basic settings, not measuring blocks). Depress and hold brake pedal to run the automated test. The engine RPMs should raise to around 1400. Field 1 is post-cat sensor voltage. It must fluctuate slightly between 0 and 1V. Field 4 will say either ‘TEST OFF/ON’ before/while the test is running and either ‘B1-S2 OK’ (sensor is good) or ‘B1-S2 NOT OK’ (sensor is bad) after the test is finished. Release the brake pedal after the test finishes.

Block 034 - Aging of Pre-Cat Oxygen Sensor

  • Go to Block 034 (this test must be done in basic settings, not measuring blocks). Depress and hold brake pedal to run the automated test. The engine RPMs should raise to around 1400. Field 1 is the engine speed. Field 2 is the catalytic converter temp. Field 3 is the value which tells you how aged the sensor is (not sure what it’s called). Field 4 will say either ‘TEST OFF/ON’ before/while the test is running and either ‘B1-S1 OK’ or ‘B1-S1 NOT OK’ after the test is finished. The aging value must be above 0.80. The value for a new sensor is 1.99. The value will decrease as the sensor ages. Release the brake pedal after the test finishes.

Block 046 - Catalytic Converter
NOTE: The test in Block 034 must be done just before this test or it will NOT initiate!

  • Go to Block 046 (this test must be done in basic settings, not measuring blocks). Depress and hold brake pedal to start the automated cat. test (last approx. 100 secs - the cat needs to be warmed up above a certain threshold for an accurate reading - the threshold is usually 400°C). The engine RPMs (Field 1) should raise to around 1400. Field 2 is the cat. temp. This will also rise during the test. Field 3 is the cat. conversion efficiency. If the cat is good, the value should be below 0.50 at the end of the test. Field 4 will indicate if the cat is good (CAT B1 - OK) or bad (CAT B1 - NOT OK). Release the brake pedal after the test finishes.

16804/P0420/001056 - Catalyst System; Bank 1: Efficiency Below Threshold

Possible Causes

  • Leakage in Intake and/or Exhaust System
  • Catalyst faulty
  • Oxygen Sensor(s) faulty
  • Oxygen Sensor(s) Control faulty

Possible Solutions

  • Check Intake and Exhaust System for Leaks
  • Check Catalyst
  • Check Oxygen Sensor(s)
  • Check Oxygen Sensor(s) Control
    • Perform Oxygen Sensor(s) Aging Check

Awesome information, thank you! I ran some tests last night. The car failed the b1s1 test and the cat test (the value was .65). My vcds can only display advanced measuring values, so I couldn’t find the aging value block for b1s1. I’ll remember to get a new sensor when I get my 3" downpipe

How many miles on the car/engine? Are you going Catless with the new downpipe? 2.0t should be pretty responsive. At least the S2 O2 sensor is pretty easy on the 2.0t, harder on the 3.0t and a lot harder on the 4.2 RS5.

280,000 km on body, unknown mileage on engine/trans. I inspected the timing chain tensioner when I first got the car and it is the new style one. I noticed witness marks on all of the bell housing bolts, so wondering if the whole engine was replaced. It drives fantastically, it just isn’t as snappy down low as I feel it should. I have zero oil consumption between oil changes after running 5w40 and replacing pcv. I haven’t really gotten a clear answer on whether my car is running normally or not

Sorry to post in an old thread. I serviced the car over the weekend and found that my waste gate is pretty loose. It actually has a bit of play so it is probably cracked open all the time and I’m not getting good low rpm boost. It sucks that the actuator rod isn’t threaded so I can’t adjust it to compensate. I guess it’s time for a k04

If you have Vagcom you can take the car for a drive and data log the boost and see if you’re actual boost is close to requested boost. At lower RPM’s the requested is usually always higher than actual due to Turbo lag. Do a full throttle pull from 1500 to 5000/6000 rpm’s in 3rd gear (manual) or 4th gear (DSG).