That's good to know about the robustness of the ECUs. I agree that I should be checking the parameters of various sensors and whatnot, if only I had a BHW or even a BEW manual. I assume the CCV pigtail is the shorter of the two. I have all the bits n' bobs I've removed from the engine, and can return everything to stock...as a last resort. I removed those items as much for accessibility as the desire to eliminate unsightly and unwanted weight. I really like the longitudinal arrangement for its relative ease of service as opposed to transverse, and I like furthering that goal as much as possible. Moving the N75 is probably my favorite mod.
'04 Sir Limps A Lot; the saga continues
- Thread starter Zeitgeist
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borninabus
Veteran Member
i mentioned this before and maybe you've already crossed this bridge, but is your torque converter locking up like it should?
zzdiesel
Veteran Member
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- Dec 10, 2010
- Location
- sask. mostly now Wa.
- TDI
- 05 passat tdi Geared BSM and Bewcam 2nd 2005 deleted ,converted and bew cam stage 2 Malone3 tune.
Why do you have these ECUs. If you are stuffing a BHW into another vehicle do you not need an ECU to control the engine?
zzdiesel
Veteran Member
- Joined
- Dec 10, 2010
- Location
- sask. mostly now Wa.
- TDI
- 05 passat tdi Geared BSM and Bewcam 2nd 2005 deleted ,converted and bew cam stage 2 Malone3 tune.
Thanks Quick
Man, an AWD TDI sure would be sweet. Our old C4 Avant was absolutely unstoppable in the snow, especially with the locking rear diff. I always wanted to source a Euro AEL to swap in for the anemic V6 we got here.
I'm not entirely sure if it is or not. I have no frame of reference to use as a good guide. The power delivery often feels uneven, which could be the TC slipping I guess. I don't get any TCU faults, except for an occasional gear selector implausible or something like that.
borninabus
Veteran Member
pay me some shipping and i'll send you a TCU 
you know there are some grounds and factory splices to look at, right?
any moisture under the carpets?
TCU and loom are on the passenger side.
down the outside of the footwell and the unit is under the seat. you should investigate!
it's been a while since i've been behind the wheel of a B5, but the the RPMs shouldn't flair...if you know what i mean. should respond like a MT most of the time except under light loads. i seem to remember "mozambiquer" dealing with this and a solution.
just MT swap the thing already!
you know there are some grounds and factory splices to look at, right?
any moisture under the carpets?
TCU and loom are on the passenger side.
down the outside of the footwell and the unit is under the seat. you should investigate!
it's been a while since i've been behind the wheel of a B5, but the the RPMs shouldn't flair...if you know what i mean. should respond like a MT most of the time except under light loads. i seem to remember "mozambiquer" dealing with this and a solution.
just MT swap the thing already!
Mozambiquer
Vendor , w/Business number
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- Mar 21, 2015
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- TDI
- 2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
Yup, I dealt with that, all the way out in the outer banks... My TCM was internally shorted, but water intrusion is also a common issue.pay me some shipping and i'll send you a TCU
you know there are some grounds and factory splices to look at, right?
any moisture under the carpets?
TCU and loom are on the passenger side.
down the outside of the footwell and the unit is under the seat. you should investigate!
it's been a while since i've been behind the wheel of a B5, but the the RPMs shouldn't flair...if you know what i mean. should respond like a MT most of the time except under light loads. i seem to remember "mozambiquer" dealing with this and a solution.
just MT swap the thing already!
Mozambiquer
Vendor , w/Business number
- Joined
- Mar 21, 2015
- Location
- Versailles Missouri
- TDI
- 2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
In the harness just before the TCM (i don't remember if it's before the box or inside the box) there is a ground wire splice that some cars had problems with. There's maybe 4 wires that come together, they're brown, if I recall. You'll unwrap that and solder them and then tape them back up.
DivineChaos
Top Post Dawg
Hahahahaha. Nope, I'm sure we've all thought it.
The more I think about it, I'm now thinking that a toggle switch to reset the ECU whenever it goes into limp mode makes the most sense. At least I'd have an idea that something in the parameters was amiss. But, I could reset on the fly without having to pull over, put the trans into park, turn off the key, and then turn it back on.
Invariably the car goes into limp mode on a hill with no shoulders and a super pissed off milkman in my rearview. Countless true crime novels are written with that scenario as an opening. I don't want to become a statistic.
Invariably the car goes into limp mode on a hill with no shoulders and a super pissed off milkman in my rearview. Countless true crime novels are written with that scenario as an opening. I don't want to become a statistic.
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Oh, I'm sure my whining is annoying for you old hands at these rigs. I get it. I too have been the grizzled veteran stuck with the sniveling noobs flailing about. I bought a very expensive VCDS mobile dongle, but still haven't figured out how to run comprehensive diagnostics. I also don't have a manual for a PD, let alone a BHW. To compound my frustration, I've found at least five issues that could easily have been the source of the boost problems, but resolving each of them did not resolve the problem. I'm an analog wrench now dealing with a digital realm, so I'm kinda trying to feel my way around, again without a proper manual which apparently doesn't exist. I pulled the antishudder valve and EGR because they were constantly in the way of my diagnostic tests, and to remove them from the list of potential variables adding to the mix. They are the only items I've removed. BTW, the EGR valve was one of the five issues I resolved, which could've been a source of underboost. The valve was all sooted up and wasn't returning to fully seat. I cleaned it and stiffened up the return spring--no fixee. I've tried to be methodical with my hardware tests, but in the absence of definitive digital diagnostics, I'm stuck with YouTube vids and annoying you guys for scraps of information.
Today when I fired it up for a short trip across town, it really started to feel like the torque converter was slipping. Is it possible that the slippage is behind the differential the ECU is seeing from requested and actual boost?
borninabus
Veteran Member
the TC should "slip" at certain times and lock at other times.
if it's not working right it should turn the CEL on.
i seem to think that i read of some instances of that not happening though.
got that VCDS working yet?
if it's not working right it should turn the CEL on.
i seem to think that i read of some instances of that not happening though.
got that VCDS working yet?
When one door opens, another closes. Now that it seems to be running ok, the hatch has lost enthusiasm for unlatching. It will unlock, but not release the latch. Now I get to try and figure out how the rear panel can be removed intact with the hatch in the closed position. FML
Mozambiquer
Vendor , w/Business number
- Joined
- Mar 21, 2015
- Location
- Versailles Missouri
- TDI
- 2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
Make sure it's not the gasket sticking and holding it closed. My wagon will do that once in a while, if I give it a very hard pull, then it'll open fine.
In this case, the hatch will slightly lift up when I hit the switch on the back, but it just won't fully unlatch, so no sticky rubber. I got the inner panel off, but before I could dive deeper trick or treaters chased me into full retreat into my shop. It appears the latch mechanism is solely triggered by an electrical solenoid, which seems kinda dumb, but I might be wrong.
Oookay...I had steeled myself for a deep dive into the hatch mechanism, when I just randomly pulled up on the cable and it easily unlatched, and has done so ever since. I pulled up on that cable a dozen times the other day and it would only unlock the latch, I'm now wondering if this might be an issue with moisture in the body module under the driver carpet. I'll pull that today and investigate. FML.
We've now driven the car all around town on at least six different occasions and it hasn't gone into limp mode. Mind you, I've done nothing to the engine since the last bout of limparoo. Arbitrary and capricious.
We've now driven the car all around town on at least six different occasions and it hasn't gone into limp mode. Mind you, I've done nothing to the engine since the last bout of limparoo. Arbitrary and capricious.
The saga continues...
Based on lots of advice I've gleaned all over the interwebz, I decided to pull the battery and bracket to clean out the drains--they were fully clogged. I also noticed that there was a fair amount of standing water up near the ECU suitcase. This was due to detritus being packed in under and around the suitcase, so I decided to pull it, and I'm glad I did. There was so much that all pathways to drain off water up there were blocked. All resolved.
Today I packed the wife and remaining home-based kiddo for a trip up to my dad's new place in Bremerton to help him empty the moving van. The Passat did great for our inaugural road trip since the purchase months ago. No hiccups on the way up whatsoever, and we drove for sustained periods @ 75mph. After dropping the Uhaul off and toting my dad around for a few errands, the petulant little ***** decided to randomly start slipping the TC, and then later that fixed itself, and the limp mode came back--as in every 8 mins of driving time. Luckily my dad has a Sprinter-based RV, so he's familiar with limp mode fun n' games. After we got back to his place, I plugged in my generic code reader and cleared all the EGR/shuttervalve and underboost codes. The former codes are always there, but the latter only comes on during limpy episodes.
I packed up the family and began driving back home. It seemed ok, and then...BAM it cut power and I'm ****ting myself. Am I going to need to do this for sixty miles? I stopped at a light and cycled the key. I babied it for for the next 10 miles, but that was the last of the *****iness for the remainder of the trip. I really don't understand the arbitrary randomness of this kind of annoyance. It's maddening.
Based on lots of advice I've gleaned all over the interwebz, I decided to pull the battery and bracket to clean out the drains--they were fully clogged. I also noticed that there was a fair amount of standing water up near the ECU suitcase. This was due to detritus being packed in under and around the suitcase, so I decided to pull it, and I'm glad I did. There was so much that all pathways to drain off water up there were blocked. All resolved.
Today I packed the wife and remaining home-based kiddo for a trip up to my dad's new place in Bremerton to help him empty the moving van. The Passat did great for our inaugural road trip since the purchase months ago. No hiccups on the way up whatsoever, and we drove for sustained periods @ 75mph. After dropping the Uhaul off and toting my dad around for a few errands, the petulant little ***** decided to randomly start slipping the TC, and then later that fixed itself, and the limp mode came back--as in every 8 mins of driving time. Luckily my dad has a Sprinter-based RV, so he's familiar with limp mode fun n' games. After we got back to his place, I plugged in my generic code reader and cleared all the EGR/shuttervalve and underboost codes. The former codes are always there, but the latter only comes on during limpy episodes.
I packed up the family and began driving back home. It seemed ok, and then...BAM it cut power and I'm ****ting myself. Am I going to need to do this for sixty miles? I stopped at a light and cycled the key. I babied it for for the next 10 miles, but that was the last of the *****iness for the remainder of the trip. I really don't understand the arbitrary randomness of this kind of annoyance. It's maddening.
Scubanero
Veteran Member
TC fixed itself? That seems pretty likely.
All I can tell you is that it stopped slipping as it had been earlier. It was having a hard time pulling away from a stop, but then it didn't do that. I have no good explanation for that behavior. I'm only providing a diary of observations and actions on my part. I've been wrenching on cars for over forty years, but nothing about this car comports with my previous experiences or observations. Everything is random and arbitrary.
Scubanero
Veteran Member
Failure to lock up is a common enough problem, but; the TC is not supposed to be locked when you pull away from a stop. Having a hard time pulling away from a stop sounds more like transmission limp mode.
Just a quick question...
Do these ECUs adapt or "learn" from repeated exposure to certain driving types and input parameters? We've been daily driving the car with no limp modes to report, despite having done nothing additional to the engine at all. This is unknown diagnostic territory for me, so I'm just wondering how to explain this turn of events. I can pull hills and high engine load situations that previously triggered limp mode, and it just goes and goes.
Do these ECUs adapt or "learn" from repeated exposure to certain driving types and input parameters? We've been daily driving the car with no limp modes to report, despite having done nothing additional to the engine at all. This is unknown diagnostic territory for me, so I'm just wondering how to explain this turn of events. I can pull hills and high engine load situations that previously triggered limp mode, and it just goes and goes.