p0252 after engine swap

steve6

Veteran Member
Joined
May 25, 2010
Location
Beaverton, ON
TDI
2003 jetta tdi
I swapped a ALH from one car to another, as a result of the accessory bracket breaking I swapped a good one on (had to take IP off.. etc). System was all re-timed, I know the crank and cam are aligned ok, but maybe the IP would need adjustment, I had to take the pulley off so could being out too much cause this issue?

I changed the fuel filter.

16636 = P0252

Injection Pump Metering Control (A) Range/Performance


I have searched and read various threads, most seem to die off without a resolution.. has anyone here battled this code and didn't result in having to swap the IP out entirely? I had to take the pulley off the IP so could being out too much cause this issue?

I know my IQ setting is low.. but it was like that before, I don't have full vcds to adjust it, only VCDS Lite. The car starts and runs OK, a bit of idle hesitation here and there (it used to do this).

I plan to play around with turning the pulley on the IP counterclockwise this weekend.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Odd that code's not in the Ross Tech wiki.
Might be a good idea to check basic timing, crank at TDC, cam at TDC (slot aligns), pump pin close.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
I swapped a ALH from one car to another, as a result of the accessory bracket breaking I swapped a good one on (had to take IP off.. etc). System was all re-timed, I know the crank and cam are aligned ok, but maybe the IP would need adjustment, I had to take the pulley off so could being out too much cause this issue?
Did you take the center nut off or the 3 bolts.
I think the center nut might mean sending the pump to have it installed exactly at the right place.
 

derek5120

Veteran Member
Joined
Sep 25, 2014
Location
Arthur Ont.
TDI
2003 jetta GLS
Did you check your electrical connection and make sure there is no pin tension issues and that they are clean? easiest things first. According to Prodemand the lift sensor can throw that code also, it should have 80-120ohms . Disconnect the 10pin connector for the injection pump, with battery disconnected, check the resistance between pin9-pin10, you should have 12-20ohms. If you dont, then pump needs to come apart. Those pins are the last pins in the row closest to the rounded end.
 

steve6

Veteran Member
Joined
May 25, 2010
Location
Beaverton, ON
TDI
2003 jetta tdi
So I adjusted the pulley on the IP shaft.. and so far the code has gone away entirely. The running bad was the IP hoses popped off so wasn't building boost properly. Hopefully all good for now.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
'The running bad was the IP hoses popped off ' ??

Which hoses?
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
The lower hose. I had pulled it apart at the elbow and didn't get it back together tight.
That will do it.
I forgot to put one of my clamps on once.
Didn't make it around the corner & the hose popped off.
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
So I adjusted the pulley on the IP shaft.. and so far the code has gone away entirely. The running bad was the IP hoses popped off so wasn't building boost properly. Hopefully all good for now.
i'm having this same issue p0252 !!!! i installed 2 new pumps and this code keeps popping up the engine timing and the IQ has been set
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
Did you check your electrical connection and make sure there is no pin tension issues and that they are clean? easiest things first. According to Prodemand the lift sensor can throw that code also, it should have 80-120ohms . Disconnect the 10pin connector for the injection pump, with battery disconnected, check the resistance between pin9-pin10, you should have 12-20ohms. If you dont, then pump needs to come apart. Those pins are the last pins in the row closest to the rounded end.
i'm having this issue and i have a new pump on the car, what lift sensor are you referring to? the #3 injector lift sensor? i just had these injectors rebuilt with a new set of nozzles and are you saying pin 9 and 10 should have 12-20ohms each
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
i'm having this issue and i have a new pump on the car, what lift sensor are you referring to? the #3 injector lift sensor? i just had these injectors rebuilt with a new set of nozzles
Yes. Lift sensor may not have been tested during rebuild.
and are you saying pin 9 and 10 should have 12-20ohms each
No, that should be the resistance between pins
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
Yes. Lift sensor may not have been tested during rebuild.
No, that should be the resistance between pins
i disconnected the battery but i'm not sure if i'm checking the right pins i'm touching the last 2 pins on the bottom row closest to the curved end and i'm getting a reading of 4.39 and i'm getting power to the #3 lift sensor but i'll have to double check the reading my probes keep slipping but the reading was low for a brief moment the only reason i sent the injectors out was because i had them pop tested and they were between 170-190 not 210 all of this happened simultaneously
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
Yes. Lift sensor may not have been tested during rebuild.
No, that should be the resistance between pins
i'm at 88.1 on the lift sensor..... with that low reading on the ip connector should i be looking for a bad wire or possibly a bad ecu
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
That's good

You found the IP to have lower than expected resistance, correct?

Sounds like an IP issue to me.
[/Q
i think i read the thread wrong are we talking the connector on the ip or the connection coming from the wiring harness
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
Didn't answer my question, but I'm not sure there's value in measuring the harness side nor what a normal reading would be.
do you think it's plausible that the crank is out of sync with the cam causing this issue?
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Not sure what your issue is (not OP), but yes if the mechanical timing is off you'll have issues.
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
ohhhh i'm getting zero on the ip side and there's power to the plug going to the pump
If there's actually 0 ohms on the IP side I would expect blown fuses because that's a dead short.
do you think it's plausible that the crank is out of sync with the cam causing this issue?
No, but IP out of sync can cause it - see post #6, the reason I referred you to this thread in the first place.
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
Yes, the crank, cam and IP must be synchronized, that is basic timing.
I am referring to the possibility of the pump shaft and pulley being out of sync - again, see post #6

This relationship should be set when the pump is assembled and not messed with subsequently, but if it was an issue for the OP it's worth considering as a possibility by @1kmiletdi given he installed a rebuilt IP.
 
Last edited:

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
If there's actually 0 ohms on the IP side I would expect blown fuses because that's a dead short.

No, but IP out of sync can cause it - see post #6, the reason I referred you to this thread in the first place.
the 2 fuses are good i think they're 28 and 34 i'm so goddamm annoyed and the guys i got the pump from are just deflecting and saying its something else, they're suggesting that the crank is out of time with the cam, my buddy and i have set the IQ and the engine timing, the cel comes on maybe 10 seconds or so after it starts it will erase and only come back on after i restart the car, the ohm reading on #3 injector was within spec, they're suggesting the #3 injector isn't seeing the cold start advance it should so its setting off the cel isn't the cold start related to the N108? i appreciate everyone's feedback am i missing something?
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
they're suggesting that the crank is out of time with the cam, my buddy and i have set the IQ and the engine timing
Have you verified static timing using the lockdown tools? If not you cannot be certain the timing is correct, regardless of what a scan tool says.
the cel comes on maybe 10 seconds or so after it starts it will erase and only come back on after i restart the car, the ohm reading on #3 injector was within spec, they're suggesting the #3 injector isn't seeing the cold start advance it should so its setting off the cel
Does the CEL come on every time you restart the car? Or only on a cold start?

They may be correct about #3 not seeing the expected advance - but if so that points to the pump because N108 advances the pump, #3 just measures it.
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
Have you verified static timing using the lockdown tools? If not you cannot be certain the timing is correct, regardless of what a scan tool says.

Does the CEL come on every time you restart the car? Or only on a cold start?

They may be correct about #3 not seeing the expected advance - but if so that points to the pump because N108 advances the pump, #3 just measures it.
yes i have used the lockdown tools to set the static timing.... and yes i've let the car fully warm up i've taken it for a ride up an down the highway came back shut it off and restarted the car and the cel comes on again... that's what i thought the N108 controls the cold start advance
 

1kmiletdi

Active member
Joined
Sep 14, 2024
Location
ocala,fl
TDI
mk4
If there's actually 0 ohms on the IP side I would expect blown fuses because that's a dead short.

No, but IP out of sync can cause it - see post #6, the reason I referred you to this thread in the first place.
it turned out to be the IP needed to be retarded further but now my turbo has failed !! ..... does anyone have a good turbo they would sell?
 
Top