Increased fuel consumption after timing belt replacement 1.9TDI AVF

Hello everyone

This topic has certainly been discussed many times, however, even extensive research has not yet led to a solution for my problem.
I am driving an Audi A4 B6 with the 1.9 TDI AVF engine. Two weeks ago, I replaced the timing belt, along with the tensioner pulley, water pump, and V-belt with pulleys. So, essentially, I replaced everything . I used a timing belt marking tool. After the change, the synchronization angle was set to 1°, and then I changed it to 0°.

However, since then, consumption has increased by 0.5-1 liter compared to before, and even 2-3 liters in urban areas. In addition, the oil temperature is 5 degrees higher. Currently, the fuel consumption without lights, air conditioning, etc., is 0.8l/h. Previously, it was 0.4-0.6...

Besides the fact that the installed water pump from Contitech looked "simpler" (simple metal blades) compared to the original, I didn't notice any other differences.

I came across a forum post where an Audi mechanic apparently noticed, at first glance, that the camshaft pulley had been shifted by one tooth during the timing belt replacement, and he apparently corrected it immediately, after which the fuel consumption returned to normal. What do you think of this? Is it really possible to misalign the camshaft by one tooth, even with a measuring tool? How could this be checked? "Removing the crankshaft without disassembling everything...
Do you have any other ideas of what I could do?

Thank you in advance.

Tobias

Hi

How many times did you fill up the tank and how many kilometers did you drive to determine your actual fuel consumption before and after the timing belt replacement?

Hello

Estimated consumption before approximately 50,000 km Consumption after approximately 1,000 km, however, my car is driven very consistently. The values I have provided above are from the FIS or VCDS (instantaneous fuel consumption). The actual fuel consumption is approximately 0.5 liters higher, but this was only measured over one tankful. (I always fill the tank completely (gauge below 0) and then fill it up to the brim again), so it should be comparable.

Is there an OT marking on the flywheel, and if so, how accessible is it? Then, you could re-check the KW/NW position without having to disassemble everything...

Thank you and best regards.

Tobias

tobias_ wrote:

Is it really possible to misalign the camshaft, even with a measuring tool?

Yes, that is possible. NW-Lineal also also also also also also also also also also also also also also also also also also also also also also also also also also also also also also also

Greetings

Bo

tobias_ wrote:

Is there an OT marking on the flywheel, and if so, how accessible is it? Then, you could re-check the KW/NW position without having to disassemble everything...

The shock absorbers need to be removed. Don't have to break everything down.

I didn't use the NW-Lineal, and it wasn't mentioned in the instructions either. Thought you only needed it with VEP.
It's practically impossible to get the shock absorbers down without first loosening the struts, as there's hardly any space...

So, you don't need the ruler for the PD. It's best to check the position first using the OT marking, coupling flange, and camshaft position. Log Synchronization Angle.

Safer is: Remove the timing belt (I only did this when installing the longer one, as it wouldn't be an issue there), install the KW stop, and remove the camshaft.

There are also several technical articles here that describe what happens if the "early" or "late" setting is used. Additionally, there are tools for adjusting PD elements... please review these first...


Did you definitely set the NW to the maximum position after unplugging it, or would you like to describe how you set it up?

matthiasTDI96 wrote:

So, you don't need a ruler for the PD.

Okay. Was ist AVG? Sorry!

matthiasTDI96 wrote:

So, you don't need the ruler for the PD. It's best to check the position first using the OT marking, coupling flange, and camshaft position. Log Synchronization Angle. Safer is: Remove the timing belt (I only did this when installing the longer one, as it wouldn't be an issue there), install the KW stop, and remove the camshaft. There are also several technical articles here that describe what happens if the "early" or "late" setting is used. Additionally, there are tools for adjusting PD elements... please review these first... Did you definitely set the NW to the maximum after unplugging it, or would you like to describe how you set it up?

I will do this tonight. As mentioned, the synchronization angle is now set to 0°, it was directly after the change at 1°. Before the change, it was 3rd.
My engine is also mounted longitudinally, but between the pulley and the radiator, there is only about 2-3cm... Have you removed them without doing anything else?

I have already read and, in my opinion, understood the technical articles. When assembling, I simply loosened the screws on the NW wheel, placed the belt, tightened it, and then tightened the screws. I used the dampened tension roller. The screws on the NW wheel are essentially centered in the long holes.

Best regards, Tobias

Oops...that's what happens when you don't know : I meant diagonally (Golf IV ASZ)...

Hello,

When dealing with 1.9 PD-TDI engines, VCDS doesn't show you your current position, but rather indicates where you need to go.

So, if the 1° in the MWB field represents the NW, then the KW is -1° and you need to add 1° to get to zero.

Starting with the 2.0TDI, this was changed in the VCDS software. In the MWB field, the actual value is displayed, not the value to be corrected. I've already fallen over myself.

Consequently, your NW (presumably referring to a specific measurement or indicator) was -3° lower than the previous week, indicating a "late" condition.

Could the characteristic be made "tamer," while also achieving more torque in the lower RPM range, thus creating a more fuel-efficient effect.

I've already tried a few things on my (originally B6 with AVF and still using AMF) car, and I found that adjusting the timing by 0.5-1.0 degrees in the positive direction (advanced timing) gives the best combination of fuel consumption and engine smoothness.
Due to elongation, the slack in the timing belt increases to approximately +0.3°.

Just drive for a while, and only think about refueling, forget about the FIS.

Yes, the synchronization angle is absolutely correct, no matter where the NW wheel is located; it is measured directly at the NW hub's sensor. Your position is definitely correct. If your long holes are now perfectly centered, you have done everything correctly.

Greetings, Mpire

I also thought that the position was fixed. But I am so free and I can link a post from another forum.

More Consumption (BC) after Timing Belt Change - 1.9L TDI AVF

**Page 4**

**User:** A4Freunde_Fan

**Date:** 2015-03-18 14:35:22

**Subject:** Re: More Consumption (BC) after Timing Belt Change - 1.9L TDI AVF

Hi everyone,

I'm also experiencing increased fuel consumption after replacing the timing belt on my 1.9L TDI AVF. I replaced the belt, water pump, tensioner, and idler pulley. I used a new coolant flush and filled the system with new coolant.

I'm not sure if this is normal, or if something else is wrong. Has anyone else experienced this?

I'm thinking it could be the new tensioner, or maybe the new water pump is not sealing properly.

I'm going to take it to a mechanic to have them check it out.

Thanks for your help!

**User:** A4Freunde_Fan

**Date:** 2015-03-18 14:35:22

**Subject:** Re: More Consumption (

Link funktioniert only partially, it's on page 4...

I still don't quite understand why the red marking is there. Normally, at the OT on the NW, the marking is where the two nostrils are closest together...

I drove again earlier, only in city traffic, and my average fuel consumption was 15 liters. I had never experienced this before

Greetings

Okay. I just checked again, I've set the engine to OT using the flywheel marking (removing the air intake pipe greatly improves visibility ), and the marking pin fits perfectly into the NW wheel. So, it should fit perfectly . What's interesting is only the significantly higher FIS figure, but well, they are just calculated values anyway, and my car has already done 360,000 km
I will now drive for a while and see what the actual fuel consumption is. Thank you in advance for your responses

Update

Since the engine swap, I've now done almost 2000km, and the fuel consumption is still around 7 liters. (Determined by refilling and calculating) I've checked the valve timing multiple times using the "peek-hole" method on the transmission, and it seems to be correct. Nevertheless, I'm considering having the engine properly checked again next weekend. What other ideas do you have?

Air filter is new, air mass is slightly above the target value, G62 is showing correctly, the boost pressure control is functioning and the set/actual values match.

I notice that the current consumption has increased dramatically. When starting, I was in 1st gear earlier. Maybe 15-20 liters, but now it's 40 liters.
According to BC, consumption in the city increased by approximately 2 liters (same route, comparable conditions), while on the highway, the difference is smaller, approximately 1 liter.

I also replaced the water pump (old/new see pictures). The new one has a different impeller, which shouldn't make such a significant difference in fuel consumption, though? The entire timing belt kit is from Contitech, including the Poly-V belt and the pulleys.

I was still considering a difficult-to-operate tension/guide pulley or something similar, but I can hardly imagine that such a component could cause such a difference in consumption.

The synchronization angle is cold at 1-1.5° after being set using the peep hole method. At a warm engine, it is 0.0°. Are there any learning values that can be reset? I was thinking that the synchronization angle BEFORE the change was 3.0 degrees. Could it be that the control unit has now adjusted itself, and I am now off by 0.0?

Winter tires haven't been installed yet. The fuel consumption has been quite constant since I got the car (summer/winter doesn't matter) at 6-6.2 liters. Interestingly, the oil temperature has also increased. Previously, I had approximately 80° on the highway at 130 km/h (values from a self-installed display, sensor in the drain screw)

What else could I do? I'm running out of ideas and I just don't get it

I am not the specialist here, but the temperature sensor definitely seems to be broken.
Not that a cable was damaged during assembly, and the control unit thinks it's winter...
It's really easy to read.
Best regards, Frank

Yes, the coolant temperature sensor is working, as are the oil and fuel temperature sensors.