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drexer13
08-04-2014, 01:46 PM
I have had this car for about 2 years, it’s a 1999.5 a4 with a 2.8. When I first bought it I replaced the timing belt, both cam chains and tensioners, battery, vacuum lines, and coolant temp sensor. A few weeks ago it started having some problems starting but it would still run fine after it was started. Then one day it stalled at a light and I had to use starting fluid to get it going again.

Now the car won’t start at all,[headbang] it still cranks but won’t start, if I use starting fluid it will fire but still won’t stay running. I hooked the car to my scanner and it is throwing code P0322 “engine speed sensor” and P0411 “Air injection system incorrect flow”

So far I have
-Checked spark plugs
-Tested for spark
-Replaced the Crank Position Sensor. (Replaced it twice still throws the code)
-Checked all fuses
-Tested the fuel pump relay

The fuel pump only runs if I jump the relay, it does not prime when I turn the key, I tried jumping the relay and seeing if it will start and still nothing. It acts like its not getting gas but even when I hot wire the fuel pump it still does not start.

I’m thinking about replacing the fuel pump even thou I can hear running when I jump it, and also replacing the relay. After that I’m out of ideas

If anyone has any ideas I would really appreciate it

Thanks

turbo3
08-04-2014, 02:37 PM
P0332 is for a bad knock sensor

drexer13
08-04-2014, 03:05 PM
Sorry, meant P0322
Ill just go ahead and edit that.

walky_talky20
08-04-2014, 04:04 PM
From your list above I cannot tell what we have right now. You checked for spark, but that was like...2 chinese crank sensors ago.

So at the present moment, I would check the following:

1 - The codes
2 - Coolant temp reading in ECU
3 - Presence of spark during cranking
4 - Injector pulse during cranking
5 - Fuel pressure during cranking

If all of that checks out I might continue with:

6 - Scope the crank and cam sensors
7 - Try known good ECU

drexer13
08-04-2014, 04:46 PM
Thanks for responding, I really appreciate the help.

I scanned for codes and checked for spark right after I installed the second Bosch Sensor.

I will check back after I have confirmed the rest.

Thanks again

drexer13
08-07-2014, 12:02 AM
Today I
1- I cleared all the codes and then tried to start the car. Car still didn't start, re scanned the car for codes and P0322 came back. The car is still not getting a signal from the engine speed sensor.
2- Coolant temp sensor is reading 95 deg
3- Checked for spark while cranking and all 6 cylinders have spark
4- Used injector noid light to check for injector pulse while cranking. The injectors are not firing, even when I bypass the fuel relay and give them power.
5- There is no fuel pressure when cranking because fuel relay is not being energized by the ECU. I have tried bypassing the relay and giving power to both the fuel pump and injectors. car still wont start.
The ECU is not providing a ground for the fuel pump relay, and is also not providing a grounding pulse for the injectors.

I decided to try to diagnose the engine speed sensor problem so I tested for continuity between sensor terminal 2 and ECU terminal 63 (blue wire), it tested good. I also checked between terminals 3 and 56 (Gray wire) and it was also good. Terminal 1 on the sensor is black, it connects to quite a few other components then ends up at ECU terminal 67. According to my diagram the wire does not connect to any outside grounds so the ECU must supply the ground for all of these components. I tested for continuity between terminals 1 and 67 and its good.

Next I thought that maybe the ECU was not getting a good ground so I looked for a direct ground going into the ECU. The only one I could find was ECU terminal 2, so I checked for continuity between ECU terminal 2 and the negative battery cable and it also tested good.

Last I tested to make sure the ECU was getting power. On the diagram its shows that ECU terminal 3 (Red wire) runs directly to the battery and is hot at all times. I tested it for voltage and its getting 12.9 volts, same as the Battery. The diagram also shows that ECU terminal #1 runs to fuse 32 and is hot in the start and on position. I turned the key and tested, its was also getting 12.9 volts.

I also tested to make sure that the fuel relay was getting power, the relay is getting power but the ecu is not providing the grounding signal.

I leaning toward the Ecu being bad, but that would suck to replace that and still have in not start.
if anyone has any suggestion I would really appreciate it

Thanks

AudiFreaks4
08-12-2014, 07:06 PM
how do the PID's look?