Code P1252

[Truckdriver09]

I have a 1997 volkswagen passat TDI. Yesterday I was accelerating from a stoplight and suddenly I lost a lot of power, like it went into limp mode. Of course the check engine light came on and when I made it home, I scanned it and it showed code P1252 Commencement of injection valve: open or short to ground. I cleared the code and it came back again today on my way home from work.

I had this same issue a few months back, I had taken it to 4 different mechanics before one was actually able to tell me what was wrong. The first mechanic did nothing but scan the computer and told me what I already knew...didn't even do any diagnosing, the second mechanic didn't even look at my car and it sat in his shop for a week, the third mechanic claimed I needed either a new computer or wiring harness, the fourth mechanic told me that he found that the wastegate on the turbo was stuck closed and he applied vacuum to try to get it to open and he said it was still stuck closed. He said it was likely that I need a new turbo.

Once I got home from the shop, I decided to go ahead and adjust the shifter cable because I have been needing to do it for quite some time and after I adjusted it, the car suddenly started driving like normal...lots of acceleration. Now, I do not know if it was just coincidence that after I adjusted the shifter cable that it started driving normally...I don't know, but I don't see how that could have anything to do with the car losing so much power. Perhaps the mechanic applying vacuum to the wastegate had something to do with it? Should I try this myself and see if it does anything or should I do something else?

I appreciate any input. Sorry for the long post, I figured it would be best to provide all of the details.

Thanks

[Keithuk]

Well that code means as you my know:

VAG Error Code: 17660
EOBD II Error Code: P1252

Fault Location:
Fuel Injection Timing Solenoid - Open Circuit/Short to Earth

Possible Cause:
Wiring open circuit/short to earth.
Fuel injection timing solenoid.

As taken from my Free EOBD II Error Codes software

You can check out the VNT checking in FAQ.

[Truckdriver09]

I cleared the code last night and today on my way home from work, the check engine light came on and sure enough, I lose a lot of power.

I scanned the computer and these are the codes that I pulled directly from VCDS.

P1252 - Commencement of Injection Valve (N108): Open or short to Ground
P1248 - Start of Injection Timing Regulation: Control Deviation

[Keithuk]

Remember that clearing the codes doesn't fix anything it only clears the ecu memory you still have to investigate the causes.

VAG Error Code: 17660
EOBD II Error Code: P1252

Fault Location:Fuel
Injection Timing Solenoid - Open Circuit/Short to Earth

Possible Cause:
Wiring open circuit/short to earth.
Fuel injection timing solenoid.


VAG Error Code: 17656
EOBD II Error Code: P1248

Fault Location:
Start of Injection Timing Regulation - Control deviation

Possible Cause:
Loss of Power at high Engine Speeds.
Engine difficult to Start.

Start of Injection Timing Regulation not OK.
Injection Pump Control Range blocked/dirty (e.g. by Metal Particles).
Engine has stalled / ran out of Fuel recently.
Wiring/Connectors from/to Injection Valve (N108) faulty.

Possible Solutions:
Check/Adjust Injection Start. See TDI Timing Checker
Check Fuel Supply.
Check/Replace Fuse(s).
Check/Repair Wiring/Connectors from/to Injection Valve (N108).
Run Output Tests.

Special Notes:
Might by stored with other codes like 17654/P1246/004678.
When stored in the VW (9M/1J) Golf/Jetta or (1C) Beetle with the ALH engine code Tech Tip 23-02-03 may be helpful. The summary involves removing power at idle to the N108 Cold Start Injection Valve (Fuse 34 on those body styles) while monitoring Basic Setting group 000.2 which is shown under "Timing" when using the TDI Timing Checker. When power is removed from N108 the live reading should change to 255.
Check Fuel Supply.
Check/Replace Fuse(s).
Check/Repair Wiring/Connectors from/to Injection Valve (N108).

Special Notes:
Might by stored with other codes like 17654/P1246/004678.

[Truckdriver09]

Thank you for the response. I'm sorry if these are stupid questions, I really don't know much about these diesels.

1. Where is the fuel injection timing solenoid and where is the injection valve?

2. How do I test these items?

3. Do these codes cause the engine to be louder than normal? because everytime my acceleration begins to suffer, the engine gets much louder and it goes away once my acceleration comes back.