Error Code P0252 on 2003 Jetta Wagon
- Thread starter sizzlin bacon
- Start date
Brett San Diego
Veteran Member
ECU. A guess, but not really a wild one. And, relatively easy to swap.
Brett
Brett
thanks brett my buddy and i were heading down that path, we set the IQ checked the fuses and the wiring the pump is getting power, are these ECU's interchangable plug and go? or will a software update be needed
P2B
Top Post Dawg
You would need to delete the immobilizer or adapt the replacement ECU:
Immobilizer III ECU Swapping - Ross-Tech Wiki
However you have a "new" pump that is throwing a pump calibration code, so my first guess would not be an ECU issue
Why was the pump replaced? Did the P0252 code also appear before the pump replacement? Where did you obtain the new pump?
well the pump that was on the car when i got it threw a code that i can't remember the number but it's directly related to the electrical section of these pumps and since these fools don't make that part anymore we're relegated to getting a rebuilt or new pump so i called triplet diesel in waco, tx and they sent me a pump and that pump threw code p0252 so i sent that pump back and they sent another and now this pump is throwing the same code meanwhile we set the IQ checked the fuses checked the wiring and i just doubled checked all the fuel line fittings and the fuel flow is unrestricted i have installed a fass fuel system i did change the fuel filter however not the water filter, the car rev's the car has boost it goes from 65 to 80 in a snap of your finger however with little smoke it also has a new MAFYou would need to delete the immobilizer or adapt the replacement ECU:
Immobilizer III ECU Swapping - Ross-Tech Wiki
wiki.ross-tech.com
However you have a "new" pump that is throwing a pump calibration code, so my first guess would not be an ECU issue
Why was the pump replaced? Did the P0252 code also appear before the pump replacement? Where did you obtain the new pump?
Brett San Diego
Veteran Member
Just to be 100% clear if it wasn't from P2B's reply, deleting the immobilizer renders the ECU completely plug-and-play between vehicles. As long as you don't have a tune on your original ECU to transfer, just swap in the used ECU, delete the immo yourself, and drive. Or swap in an ECU with the immo already deleted. For a MY2003 Jetta, you can use a 2002 (FD suffix in part#) or 2003 (GN suffix in part#) ECU. I understand for 2002 and 2003 that the glow plug control is different vs. earlier model years, so earlier ECU's are incompatible.
I just learned to delete the immobilizer using the free KW1281test software from gmenounos. Links in my recent thread below:
forums.tdiclub.com
Brett
I just learned to delete the immobilizer using the free KW1281test software from gmenounos. Links in my recent thread below:
Where to get an ECU with IMMO delete?
2002 Jetta manual, 431,000 miles. I've got a suite of fault codes similar to others in threads here where a new ECU solved the problem. My Jetta is suddenly losing power and feels like it going into a limp home mode. I'm seeing P0234 (overboost), P1441 (EGR valve open or short circuit), P0245...
Brett
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i've installed to pumps from these guys and the same code came up p0252 and the IQ was set, is it possible its the ecu? i sent the first one back and they told me they installed it on a car and no code popped up, that feels like a lieJust to be 100% clear if it wasn't from P2B's reply, deleting the immobilizer renders the ECU completely plug-and-play between vehicles. As long as you don't have a tune on your original ECU to transfer, just swap in the used ECU, delete the immo yourself, and drive. Or swap in an ECU with the immo already deleted. For a MY2003 Jetta, you can use a 2002 (FD suffix in part#) or 2003 (GN suffix in part#) ECU. I understand for 2002 and 2003 that the glow plug control is different vs. earlier model years, so earlier ECU's are incompatible.
I just learned to delete the immobilizer using the free KW1281test software from gmenounos. Links in my recent thread below:
Where to get an ECU with IMMO delete?
2002 Jetta manual, 431,000 miles. I've got a suite of fault codes similar to others in threads here where a new ECU solved the problem. My Jetta is suddenly losing power and feels like it going into a limp home mode. I'm seeing P0234 (overboost), P1441 (EGR valve open or short circuit), P0245...
Brett
BobnOH
not-a-mechanic
Could be ECU. Could also be wiring.
P2B
Top Post Dawg
That would be a first. If you Google it, it's always the pump.
BobnOH
not-a-mechanic
True but it's had two different pumps installed. Interweb diagnostics not ideal.
we checked the power to the pump and it's getting power, i had a tune on the car from kerma but it had this awful surge at 2k i hated it and deleted it i'm wondering if that did something? it has new rebuilt injectors with 520 nozzles it had a 3 bar map sensor but it started to throw the cel so i went back to the 2.5map, these guys at triplet are telling me to look into the number 3 injector? why would i do that when it clearly says the code for the injection pump pure deflection by them
P2B
Top Post Dawg
Could still be an issue with the N108 wiring though. I have seen several posts where people reported P0252 but when they checked with VCDS it reported P1248.
If you have VCDS try the N108 wiring tests here:
17656/P1248/004680 - Ross-Tech Wiki
P2B
Top Post Dawg
Car-Part.com - Used Auto Parts Market
car-part.com
Brett San Diego
Veteran Member
Seems there's a lot of info you've been holding back for some reason.
New ECU's are NLA from dealer, at least according to my local dealer. Used, around $100 at a pick-a-part salvage yard. A little more on ebay.
I'm not arguing it's the ECU, but at least in my situation, it was very easy to swap a different one in and just see if that fixed the issue. My ALH's are all stock, so I didn't have to deal with transferring tune files.
P2B knows of what he speaks, so it's good advice.
Brett
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i wasn't trying to hold back any info, i've just done so much to this car and this scenario has been rather irritating to figure out i'm sure at the moment i was forgetting to add info, what's really eating at me is the fact that i've installed 2 pumps and they've both put out this code even after the IQ was set and we re-checked it and it stayed the same, could it be the ECU? and did that kerma tune possibly mess with the ECU, thanks P2B for the link there are a few close to me for that 100.... i don't like to throw parts at anything but this one might be worth the try.... here's something else triplet diesel sent me a email saying they put that pump on a car and it's not throwing any codes
Brett San Diego
Veteran Member
It's hard, if not impossible, to positively diagnose a problem as the ECU. It's usually the last item in the diagnostic checklist for when all else fails. The newest ALH is 21 years old. Computer failure is going to accelerate. Mine just took a dump. I picked up 2 from the salvage yards so I would have a spare.
I don't know anything specific about the P0252 code. My ECU was throwing P0216 (injection timing circuit control malfunction), which came completely out of the blue the day that it really crapped out, so my mind was thinking it could be a similar situation in your case of the ECU causing a rare fuel injection code to pop up.
Not that it's helpful, but this was my ECU's story. (For the record, I'm not so sure now that the overboost was due to the ECU failing because I have had it give an overboost a couple of times since this post.)
forums.tdiclub.com
Brett
I don't know anything specific about the P0252 code. My ECU was throwing P0216 (injection timing circuit control malfunction), which came completely out of the blue the day that it really crapped out, so my mind was thinking it could be a similar situation in your case of the ECU causing a rare fuel injection code to pop up.
Not that it's helpful, but this was my ECU's story. (For the record, I'm not so sure now that the overboost was due to the ECU failing because I have had it give an overboost a couple of times since this post.)
P0234, P1441, P0245, P0216. Fixed with new ECU
2002 Jetta, wagon, manual. 431,000 miles. For about 2 years, I've had an intermittent overboost fault and check engine light. Occasionally, the boost would drop out while driving. Some driving conditions seemed to promote the issue like being under load in 4th or 5th gear and at higher rpm...
Brett
after i installed the second pump i had that 0216 i change the fuel filter and that went away but the 0252 popped up and doesnt want to go awayIt's hard, if not impossible, to positively diagnose a problem as the ECU. It's usually the last item in the diagnostic checklist for when all else fails. The newest ALH is 21 years old. Computer failure is going to accelerate. Mine just took a dump. I picked up 2 from the salvage yards so I would have a spare.
I don't know anything specific about the P0252 code. My ECU was throwing P0216 (injection timing circuit control malfunction), which came completely out of the blue the day that it really crapped out, so my mind was thinking it could be a similar situation in your case of the ECU causing a rare fuel injection code to pop up.
Not that it's helpful, but this was my ECU's story. (For the record, I'm not so sure now that the overboost was due to the ECU failing because I have had it give an overboost a couple of times since this post.)
P0234, P1441, P0245, P0216. Fixed with new ECU
2002 Jetta, wagon, manual. 431,000 miles. For about 2 years, I've had an intermittent overboost fault and check engine light. Occasionally, the boost would drop out while driving. Some driving conditions seemed to promote the issue like being under load in 4th or 5th gear and at higher rpm...
Brett
eddieleephd
Top Post Dawg
Takes lots of reading and diagnosis to get it right
forums.tdiclub.com
800-2000 RPM Clattering/Loud Fuel Pump, Code P0252
Hey you guys and gals. I got a 2003 Jetta TDI 5 Spd with 284 k miles on it. Just had to put it's first new transmission in it a few months ago, absolutely love the car. The other day I was hearing some loud noise while accelerating and at the stop light was really able to tell. As I was...
eddieleephd
Top Post Dawg
Regardless what people tell me, the pump can be off a tooth and cause real detrimental issues adjustment of timing doesn’t correct. Reset the timing marks to TDC and check pump placement
P2B
Top Post Dawg
+1
Just reread @1kmiletdi's posts and didn't see confirmation timing has been verified using lockdown tools and VCDS.
the engine timing was set prior to replacing the pump i did a cylinder head replacement and then received the pump installed it and got p0252 sent that pump back then they sent another pump i installed that pump made the IQ adjustment with my buddies snap on scanner and the code is still popping up so that makes 2 pumps installed and popping up the same p0252 even after the IQ and engine timing was set i'm at the point of believing its solely the pump and not the ecu or wiring
P2B
Top Post Dawg
Timing needs to be set again after replacing the pump, using lockdown tools and VCDS.
Brett San Diego
Veteran Member
Oh boy. Basics... Basics...
Brett
Brett