Low power when going forward

Tiny
PROPHETIC-RICH
  • MEMBER
  • 2001 AUDI A4
  • 2.8L
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 90,000 MILES
I only have low power when going forward. When I put the car in drive the car jerks a little when I shift to drive. When I drive in reverse there is no low power but goes fast like it would when I went in drive. So going forward is very slow and the RPM’s will not go over 3,000.
I replaced the front brakes and the canister purge valve.
Do you
have the same problem?
Yes
No
Saturday, November 21st, 2020 AT 3:55 PM

7 Replies

Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi,

Are you sure one of the front brakes isn't hanging up? Did the problem start since the brakes were replaced? If you lift the front of the vehicle off the ground, can you turn each of the wheels easily?

Let me know.

Joe
Was this
answer
helpful?
Yes
No
+1
Saturday, November 21st, 2020 AT 7:57 PM
Tiny
PROPHETIC-RICH
  • MEMBER
Hey Joe,

Sorry it took me so long to respond. It has been raining.
I checked the wheel and they are free rolling.
This problem I had before I changed the front brake pads. You see I had an error code P0441- so I changed the purge valve & the brake pads cause they needed to be replaced.
One day I started the Audi and when I put it in drive the car would jolt and reverse too. This never happened! And when I put it in reverse no problem with speed, but when I put in drive slow as a turtle and if I press the gas peddle to the floor it will not go over 2,000-3,000 RPM's.
I m thinking maybe there is an electronic switch with the transmission or something, not sure.
Also could you recommend me a OBD2 scanner? There are so many to choose from like Bluedriver, Innova, etc.
Thank you for all your help!
Was this
answer
helpful?
Yes
No
Tuesday, November 24th, 2020 AT 2:18 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Have you checked the transmission fluid level and condition?

As far as the code, since it is related to the EVAP system, it could be causing the power loss Is it possible for you to record what it is doing and upload it for me to see? I have the diagnostics for the code, but it is a mile long. I'm going to provide it for you. Take a look through it and let me know if it is something you can do.

_________________________

2001 Audi A4 Quattro Sedan (8D2) V6-2.8L (ATQ)
Output Diagnostic Test Mode (DTM) (Function 03)
Vehicle Powertrain Management Computers and Control Systems Testing and Inspection Scan Tool Testing and Procedures Scan Tool Testing Output Diagnostic Test Mode (DTM) (Function 03)
OUTPUT DIAGNOSTIC TEST MODE (DTM) (FUNCTION 03)
Output Diagnostic Test Mode (DTM) (function 03)

NOTE:
- Output Diagnostic Test Mode (DTM) is only possible with engine idle and ignition switched on.
- Output Diagnostic Test Mode (DTM) is aborted if engine is started or an RPM signal is recognized.
- In output Diagnostic Test Mode (DTM), individual actuators (with the exception of the fuel injectors) are activated for approximately 1 minute unless the next actuator is selected earlier by pressing the " button.
- Actuators are checked either acoustically or by touch.
- The electric Fuel Pump (FP) runs during all of output Diagnostic Test Mode (DTM).
- Engine must be started before repeating output Diagnostic Test Mode (DTM). (ECM must recognize an engine speed of above 300 RPM).

Output Diagnostic Test Mode (DTM) activates the following components in the specified sequence:

Activation sequence
1 Evaporative Emission (EVAP) canister purge regulator valve -N80-
2 Secondary Air Injection (AIR) solenoid valve -N112-
3 Secondary Air Injection (AIR) pump relay -J299-
4 Intake manifold change-over valve -N156-
5 Camshaft adjustment 1 (Valve 1 for camshaft adjustment -N205- and valve 2 for camshaft adjustment -N208-)
6 Leak Detection Pump (LDP) tank ventilation system
7 Cylinder 1 fuel injector -N30-
8 Cylinder 4 fuel injector -N33-
9 Cylinder 3 fuel injector -N32-
10 Cylinder 6 fuel injector -N84-
11 Cylinder 2 fuel injector -N31-
12 Cylinder 5 fuel injector -N83-

Test requirement:
- Fuses for engine electronics OK

Test sequence
- Connect VAS5051 tester or VAG1551 scan tool and select the control module for engine electronics using "address word" 01.
Ignition must remain switched on for this.

When indicated on display:

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -3- to select "output Diagnostic Test Mode" and press -Q- button to confirm input.

Indicated on display:

Rapid data transfer Q
03-Output Diagnostic Test Mode

Activating the EVAP canister purge regulator valve (tank vent valve)
- Confirm input using the -Q- button.

NOTE: The Fuel Rump (FR) relay must trigger, the Fuel Pump (FR) must run, flowing noise at fuel pressure regulator is clearly audible. If Fuel Pump (FP) does not run, check activation. See: Fuel Pump Relay > Testing and Inspection

Indicated on display:

Output Diagnostic Test Mode ->
EVAP canister purge regulator valve -N80

(Indicated on VAG1551: from EVAP canister purge regulator valve -N80-)

This valve is activated for approx. 1 minute (clicks), unless -> button is pressed first to switch to the next actuator.

If valve is not activated (does not click):
- Check Evaporative Emission (EVAP) canister purge regulator valve -N80-. See: Canister Purge Control Valve > Testing and Inspection

Activating the Secondary Air Injection (AIR) solenoid valve

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Secondary air injection solenoid valve -N112

This valve is activated for approx. 1 minute (clicks), unless -> button is pressed first to switch to the next actuator.

If valve is not activated (does not click):
- Check Secondary Air Injection (AIR) solenoid valve -N112-:

Repair Manual, Engine Mechanical, Repair Group 26; Secondary Air Injection (AIR) system.

Activating the Secondary Air Injection (AIR) pump relay
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Secondary air injection pump relay -J299

The Secondary Air Injection (AIR) pump relay -J299- (in 3-socket relay carrier in the E-box, at left in the plenum chamber, position 2) switches the Secondary Air Injection (AIR) pump motor -V101- on for approx. 1 minute in intervals unless the next actuator is selected first by pressing the -> button.

If the Secondary Air Injection (AIR) pump motor -V101- does not run in intervals:
- Check Secondary Air Injection (AIR) pump relay -J299-:

Activating intake manifold change over valve
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Intake manifold changeover valve -N156

This valve is activated for approx. 1 minute (clicks), unless -> button is pressed first to switch to the next actuator.

If valve is not activated (does not click):
- Check intake manifold change-over valve -N156-. See: Variable Induction System > Testing and Inspection

Activating camshaft adjustment valves
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Camshaft adjustment 1

Valve -1- for camshaft adjustment -N205- and valve -2- for camshaft adjustment -N208- are activated for approximately 1 minute (they click) unless output Diagnostic Test Mode (DTM) is ended first by pressing the " button

If valves are not activated (do not click).
- Check camshaft adjustment valves:

Activating Leak Detection Pump (diagnostic pump for tank ventilation system)
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Leak detection pump Tank vent valve system

The change-over valve in the LDP is activated for approximately 1 minute (clicks), unless -> button is pressed first to switch to the next actuator.

NOTE: The click can be heard by listening near the rear left wheelhousing.

If valve is not activated (does not click):

Activating fuel injectors

NOTE: Fuel injectors are activated according to ignition sequence: Cyl. 1, Cyl. 4, Cyl. 3, Cyl 6 Cyl. 2, Cyl 5.

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 1 fuel injector -N30

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 1 fuel injector -N30

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 4 fuel injector -N33

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 4 fuel injector -N33

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 3 fuel injector -N32

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl 3 fuel injector -N32

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 6 fuel injector -N84

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 6 fuel injector -N84

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl 2 fuel injector -N31

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 2 fuel injector -N31

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection
- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 5 fuel injector -N83

- Press -> button.

Indicated on display:

Output Diagnostic Test Mode ->
Cyl. 5 fuel injector -N83

Fuel injector must click 5 times after arrow button is pressed.

If injector does not click:
- Check fuel injectors. Refer to "Fuel Injectors, Checking" See: Fuel Injector > Testing and Inspection

Indicated on display:

Output Diagnostic Test Mode ->
END

- Press -> button.

Indicated on display (function selection):

Rapid data transfer HELP
Select function XX

NOTE: Before re-initiating output Diagnostic Test Mode (DTM), engine must be started and the ignition must be switched off and on again.

_________________________

As far as a scan tool, I recommend getting one that is for Volkswagen / Audi (VAG). As far as brands, I'm not sure what to tell you. I have a Snap-on scanner, but that was 4K dollars. LOL It's used every day. If you watch this video that shows how to scan the can system, the one being used is a good scan tool and will be much less.

https://youtu.be/InIlnsjOVFA

Let me know what you want to spend. In all honesty, I purchased an inexpensive one from ebay for VW/Audi vehicles. It was under 30 dollars and works fine, but is very limited as to what it can do. I got it to keep in the vehicle with me. LOL

Let me know.

Joe
Was this
answer
helpful?
Yes
No
Tuesday, November 24th, 2020 AT 7:17 PM
Tiny
PROPHETIC-RICH
  • MEMBER
I have not checked the transmission fluid yet.
It is just odd that when I go in reverse it is fast, but when I go forward it is very slow and cannot rev motor more than 3,000 RPM s. I am not sure if I am going to purchase a Scan tool yet? I may have a mobile mechanic come to the house or a friend and hook it up and tell me what is going on.
Do you know what the Pressure Control Solenoid (EPC) does? Could this be possibly why I have slow speed forward and fast speed in reverse?
Was this
answer
helpful?
Yes
No
Friday, November 27th, 2020 AT 6:53 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi,

On a VW/Audi, EPC stands for Electronic Power Control. It is a computerized ignition and engine management system found in these vehicles. Could it cause issues, yes. That's why it is so important to scan for codes. Oftentimes, people start replacing parts not know the cause which can get really expensive and fix nothing. I would feel much more comfortable if you can get it scanned to see if and what codes are present.

Let me know what I can do to help.

Take care,
Joe
Was this
answer
helpful?
Yes
No
Friday, November 27th, 2020 AT 9:17 PM
Tiny
PROPHETIC-RICH
  • MEMBER
Hey Joe,

I have a friend who is a type of a mechanic and may have a (VAG) scan tool seeing all his cars are mostly VW s and Audi s. I am going to reach out to him perhaps next week and get him to the house and scan the system.
After this is done, I will send you another message and let you know what he found with the codes.
Thank you for everything and all your professional advice!
Blessings to you,
Rich
Was this
answer
helpful?
Yes
No
Saturday, November 28th, 2020 AT 11:23 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi, Rich. That sounds like a good plan. Let me know. I'll watch for your findings.

Take care,
Joe
Was this
answer
helpful?
Yes
No
Saturday, November 28th, 2020 AT 7:56 PM

Please login or register to post a reply.

Sponsored links