P0605 persists after hose fix

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Dan99TDI

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Hey guys,
Trouble shooting my new to me 98 jetta tdi.
Found the p0605, read about the split hose, fixed it, but the code persists. I left the battery unplugged for half an hour too.

No driveability issues, no hard starts, really no other symptoms.
I haven't been able to find the next diagnostic step.

Thanks
 
Mongler98

Mongler98

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get a vacuum gauge bleeder thingy and test it. if it leaks, fix it. if it does not leak or loss of vacuum then the ECU is buggered. it IS possible to Fry your board by headlining it improperly, its very unlikely but it IS possible and IT HAS happened before.
 
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KLXD

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Did you clear the Code? Unplugging the battery won't do it. I get the impression that's all you did.

Driving a while might but I doubt it.
 
Mongler98

Mongler98

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codes are stored in RAM, that will not clear unless it sits a VERY VERY LONG TIME
they will be STORED for ever but usually not cleared. some clear and dont trigger CEL but most do and this one does.
for instance most cars have a CEL for things like misfire but it will clear if the instances do not reoccur after a few hundred miles but the code and fault is still stored unless cleared and this is why a CEL will fail an emissions or inspection but faults stored will not.
 
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Dan99TDI

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I did clear the code but it didn't stay cleared long enough to read again.
What am I putting the vacuum vague on?
 
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KLXD

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The hose between the ECU and intake duct is good too? Idunno if that'll cause the same code.

There's no vacuum involved in the wastegate control. It uses manifold pressure. I wouldn't apply vacuum to a pressure transducer. Might be ok but not what it's designed for.
 
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Dan99TDI

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KLXD said:
The hose between the ECU and intake duct is good too? Idunno if that'll cause the same code.

There's no vacuum involved in the wastegate control. It uses manifold pressure. I wouldn't apply vacuum to a pressure transducer. Might be ok but not what it's designed for.
Click to expand...
Yes, I replaced the hose from the intake to computer and inside the computer.

I have a reversible brake bleeder, I'll put that hose under 10 psi and see that it's not leaking.

Any other ideas? Seems like if it were N75 related it should have driveability issues.

Also wondering if it's plumbed correctly, as the hose goes directly from the intake to the computer, and it s mentioned that perhaps the N75 should be in that loop somehow?
 
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KLXD

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N75 has its own plumbing. A hose to the TC discharge before the intercooler, a hose to the wastegate and a hose to the intake before the TC.
 
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Dan99TDI

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Interesting, thanks.
So it would seem things are pointing towards ECU. Anyone have an alternative idea I might look into? Could it be N75 despite driving fine?
 
Mongler98

Mongler98

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VW DTC 16989 (P0605) - Internal Control Module Read-Only Memory (ROM) Test Error

n75 will trip a different code.

most of the threads about this code all point to the ECU having a issue with a Tune. well all the threads i could find on this. Nothing about a boost leak.

these would be the codes you would replace the boost lines with.
00575 - Intake Manifold Pressure
17-10 - Control Difference - Intermittent
http://wiki.ross-tech.com/wiki/index.php/00575

however:
according to rosstech
Fault Codes like this can usually not be repaired since they are stored after the Control Module did not pass it's internal Self Test. Even though the official Repair Manuals suggest replacing the Control Module in such a case, there may be specialized Companies repairing Modules like this.

http://wiki.ross-tech.com/wiki/index.php/16989/P0605/001541

Please provide me with the links to your DIY threads about replacing the boost lines for this code becuase i have not found any.

AGAIN, your fault codes cant be cleared, sorry if i didnt specify that in my last post but this and a few other faults CAN NOT be cleared, well easily any ways. Im asuming you are using a generic scanner or do you have a VAG-COM cable and VCDS? you WILL need this cable tool to do this job.

90% chance you need to replace the ECU or repair it some how. Has it ever been tuned?
 
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Dan99TDI

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ALH going in a 56 CJ5, B5.5 tdi wagon
Mongler98 said:
VW DTC 16989 (P0605) - Internal Control Module Read-Only Memory (ROM) Test Error

n75 will trip a different code.

most of the threads about this code all point to the ECU having a issue with a Tune. well all the threads i could find on this. Nothing about a boost leak.

these would be the codes you would replace the boost lines with.
00575 - Intake Manifold Pressure
17-10 - Control Difference - Intermittent
http://wiki.ross-tech.com/wiki/index.php/00575

however:
according to rosstech
Fault Codes like this can usually not be repaired since they are stored after the Control Module did not pass it's internal Self Test. Even though the official Repair Manuals suggest replacing the Control Module in such a case, there may be specialized Companies repairing Modules like this.

http://wiki.ross-tech.com/wiki/index.php/16989/P0605/001541

Please provide me with the links to your DIY threads about replacing the boost lines for this code becuase i have not found any.

AGAIN, your fault codes cant be cleared, sorry if i didnt specify that in my last post but this and a few other faults CAN NOT be cleared, well easily any ways. Im asuming you are using a generic scanner or do you have a VAG-COM cable and VCDS? you WILL need this cable tool to do this job.

90% chance you need to replace the ECU or repair it some how. Has it ever been tuned?
Click to expand...
Not sure if it's ever been tuned, the previous owner didn't know either.

I'm checking them with a generic obd2 reader, I don't have the cable.

Thanks for the clarification.

Pages like this lead me to the hose, which was in fact cracked but didn't solve the issue: http://forums.tdiclub.com/showthread.php?t=198283

I have a photo of the chips in the computer because I wanted to try to figure out if it had been tuned. I'll try to upload them.
 
Mongler98

Mongler98

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OK, learned something new, i have never come across this code before and had the issue be the line.
So you WILL need VCDS to clear this code unfortunately as its stored PAST the unit.
there is a sticky here somewhere for finding people willing to share a cable via map location.
or you can buy one for a few $$$, i got mine on a good deal for $150, WORTH IT.
 
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Giberish33

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I had the same code 3 years ago when I got my 97 jetta. I changed the vac line in the ecu and cleared the code with torque pro and generic bluetooth obd2, haven't had a single check engine in those 3 years. PM me if you want to know how I setup vagcom and cable for cheap. I know its generally a no no on this forum to spread info now this because I didn't pay for it but I've only used it a handful of times when I first got the car and was diagnosing limp mode and once more when I got new nozzles and set my IQ, not worth several hundred dollars imo.
 
Mongler98

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i have used those ebay cables and a haxed version of VCDS light but i have so many issues with making it work, but i forget how i did but it did work when i messed with it for like an hour.

If the code has NOT cleared by a generic scanner OBD2 then its not going to clear with VCDS (i think) Clearing codes is no different for a gen scanner vs VCDS. This rom error is a hit or miss item.

OP if you can ensure that the repair is done properly and not leaking and all your boost lines and N75 is in working order, and clearing the code does not work, i suggest you WILL need VCDS as the generic scanners and the hacked version of VCDS does NOT have all the features that VCDS does. I had to buy the cable and do it legit because the hacked version had many of the features i needed blocked out. Means block 8 and timing worked fine though.
 
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Dan99TDI

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Can anyone here tell me if a ScanGauge would work? I'm considering one of those anyways.
Edit: saw what torque pro can do and just ordered a elm327, giving it a shot.
Thanks
 
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Mongler98

Mongler98

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98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Dan99TDI said:
Can anyone here tell me if a ScanGauge would work? I'm considering one of those anyways.
Edit: saw what torque pro can do and just ordered a elm327, giving it a shot.
Thanks
Click to expand...
NO, it will not.
Scangauge II will work as its intended but not for codes or anything like that. all it is, is a multi functional display gauge that will read out any and all things that the ECU and ONLY the ECU has a reading for, in MK3's there is NO EGT going to the ECU so that wont work, and you must custom program a few things but its easy. I love mine so much nicer to see coolant temps in real time.

again, this code is stored PAST the modual so,,,, good luck trying to clear it generically. some have but it seems this code is ECU related. its not like that hose fix is complicated.
 
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Dan99TDI

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Mongler98 said:
again, this code is stored PAST the modual so,,,, good luck trying to clear it generically. some have but it seems this code is ECU related. its not like that hose fix is complicated.
Click to expand...
Took a chance on the elm327 mini and torque pro, and was able to clear it and risked a 15 minute drive without it returning.

Thanks to the guy that suggested that, made it a $20 fix instead of hundreds.
 
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Giberish33

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1997 Jetta TDi 1z
Dan99TDI said:
Took a chance on the elm327 mini and torque pro, and was able to clear it and risked a 15 minute drive without it returning.
Thanks to the guy that suggested that, made it a $20 fix instead of hundreds.
Click to expand...
Good to hear! I also kinda freaked out when I first got the car and read the code about ROM error I thought how is it possible that the ecu is done when the car was running fine except for limp mode once in a while. I guess its possible for that code to be related to a bad ecu but it seems more common for the vac hose in the ECU to be the cause and the check engine needs to be cleared.
 
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