Subtle Surge or RPM Pulsing
#22
03-07-2013, 08:16 PM
No, it won't hurt anything other than being really irritating. Eventually the seal for the clutch will fail totally and you'll no longer have any converter lock-up (but the surge will be gone). That will give you a check engine light however.
The N80 valve is on the rear half of the intake manifold, next to where the big tube from the pressure regulating valve connects. Hose in each side, sticks over a tab on the intake for mounting.
The N80 valve is on the rear half of the intake manifold, next to where the big tube from the pressure regulating valve connects. Hose in each side, sticks over a tab on the intake for mounting.
#23
03-11-2013, 10:46 AM
I finally changed the N80 yesterday. Used regular hose clamps. The clamps that are on the hoses are PITA to get off. Shoot a little wd40 on the valve to get the hoses off.
#25
03-13-2013, 12:17 AM
No, it won't hurt anything other than being really irritating. Eventually the seal for the clutch will fail totally and you'll no longer have any converter lock-up (but the surge will be gone). That will give you a check engine light however.
The N80 valve is on the rear half of the intake manifold, next to where the big tube from the pressure regulating valve connects. Hose in each side, sticks over a tab on the intake for mounting.
The N80 valve is on the rear half of the intake manifold, next to where the big tube from the pressure regulating valve connects. Hose in each side, sticks over a tab on the intake for mounting.
#26
06-03-2013, 10:29 AM
I would bet my life (almost) it is the torque converter clutch, more specifically the seals inside the converter for the TCC piston.
On a scanner, the MVB for TCC should show "OFF" and "ON" (or "open" and "closed"). If it reads "CNTRL" constantly, it is the converter. The ECM/TCM is commanding full TCC but not "seeing" it.
ANother good test is if it gets less noticable as the trans fluid temp gets to normal.
I've replaced 5 converters in '08 A4 2.0T's in the past couple weeks, and have 2 more on order. It's a tough one to diagnose unless you've seen it before. Then it's obvious what the problem is. First inclination is that it's an engine problem.
Now, if there was only a fix for the idle vibration on these cars.................................
On a scanner, the MVB for TCC should show "OFF" and "ON" (or "open" and "closed"). If it reads "CNTRL" constantly, it is the converter. The ECM/TCM is commanding full TCC but not "seeing" it.
ANother good test is if it gets less noticable as the trans fluid temp gets to normal.
I've replaced 5 converters in '08 A4 2.0T's in the past couple weeks, and have 2 more on order. It's a tough one to diagnose unless you've seen it before. Then it's obvious what the problem is. First inclination is that it's an engine problem.
Now, if there was only a fix for the idle vibration on these cars.................................
Hello,
I I have exactly the same problem but what is different is that when the engine is cold everything works normally, the rpm does not fluctuate.
when the temperature reaches 90 ° C begin rpm fluctuations in single upshifts until 70k / h.
It will also be the torque converter?
Thank you. Greetings from Chile.
#27
02-07-2014, 10:16 AM
I would bet my life (almost) it is the torque converter clutch, more specifically the seals inside the converter for the TCC piston.
On a scanner, the MVB for TCC should show "OFF" and "ON" (or "open" and "closed"). If it reads "CNTRL" constantly, it is the converter. The ECM/TCM is commanding full TCC but not "seeing" it.
ANother good test is if it gets less noticable as the trans fluid temp gets to normal.
I've replaced 5 converters in '08 A4 2.0T's in the past couple weeks, and have 2 more on order. It's a tough one to diagnose unless you've seen it before. Then it's obvious what the problem is. First inclination is that it's an engine problem.
Now, if there was only a fix for the idle vibration on these cars.................................
On a scanner, the MVB for TCC should show "OFF" and "ON" (or "open" and "closed"). If it reads "CNTRL" constantly, it is the converter. The ECM/TCM is commanding full TCC but not "seeing" it.
ANother good test is if it gets less noticable as the trans fluid temp gets to normal.
I've replaced 5 converters in '08 A4 2.0T's in the past couple weeks, and have 2 more on order. It's a tough one to diagnose unless you've seen it before. Then it's obvious what the problem is. First inclination is that it's an engine problem.
Now, if there was only a fix for the idle vibration on these cars.................................
Started in about the past 3-4 months and is always more noticeable when the car is cold. No way I'm spending $1500 to get it fixed, though. Timing belt is also due and that's another $1200. The car's not worth $10k on the market. I guess I'll just live with it, but it's nice to know what the problem is at least.
#28
02-15-2014, 04:13 PM
hi. I have the same problem with my 08 A4 . its your torque converter. audi is noted for crappy converters. tons of threads on line about it. they still say same thing to me. every thing is with in spects. BS. they have a problem and wont address it.
#29
02-16-2014, 10:19 AM
cam follower
I was at the shop the other day working on my car and another guy cam over and started asking me some question. Then we hit the "surge/idle symptoms and he told me that it was the cam follower. Once he replaced it, the surging stopped and never did it again. The whole kit is about 60 bucks which is worth it I think. I'm planning on doing mine in the next few weeks.
#30
03-01-2016, 09:38 PM
I have a similar surging issue but I am not convinced it is the torque converter seal. My surge happens during light load in the 35 - 45 mph range. At freeway speeds the converter seems to be locked. Is there a servo in the transmission that is responsible for locking the converter that could be bad?