1999 V70 T5 Issues, ETM and Accelerator Pedal

[JeremyXR]

Hello guys and gals, Ive learned a lot from the forums over my years of volvo ownership but this is my first posting here as this 99 T5 manual is giving me fits.
I'm hoping to get some guidance on this from the experts here and this is posted over on the other Volvo forum too.
Based on the below information I plan on trying to get a used throttle pedal assembly but the ETM codes after TPS replacement have me a bit concerned.
Ive read on some occasions the ETM driver PCB can go bad.
Has anyone ever tried to Resolder the driver PCB before?

Here is the short story, see below for more work done...
Currently the car has an intermittent issue after it is started it will miss at idle on a couple cylinders and only rev to 2500-3000 rpm. When its missing on a couple cylinders it throws no codes with my generic reader.
I think this is limp mode but correct me if i'm wrong.
When the issue is occurring my generic code reader shows absolute throttle position stuck at somewhere around 17-20% even though the car is responding to throttle movements.
The issue has persisted after replacement of the Sacer TPS install from Module masters. The car currently does not have an ETS light on and No check engine light.
I took it to a shop and we scanned it with an Autel reader and found 3 ETM related intermittent codes.
ECM-9190 Throttle Unit Internal Fault; 8 cycles since fault was last validated
ECM-917F Accelerator Pedal position sensor internal fault; 6 cycles since fault was last validated
ECM-903F throttle unit internal fault; 44 cycles since fault was last validated


Some background information...the long story in chronological order....
Car has 225,000 miles and I purchased it at 180000 miles and performed maintenance since purchase.
No Modifications at all and just normal maintenance performed.
On a couple rare occasions 2-3 times the car has had a no start issue and after sitting a while it restarts.
This issue seemed fuel related but I couldn't track it down since it was so intermittent.
Car started intermittently going into limp mode on startup a few weeks ago.
Problem seems to get better if the car goes up to temp then is restarted, can drive for hours sometimes without happening.
Originally the car had an upstream O2 code around the time of problem and this was replaced with a bosch unit.
I reset the codes and that O2 code hasn't come back
Replaced the TPS with a Sacer unit but did not set the voltage as I only found this info after the replacement and continued problem.
I'm sure the install of the TPS is good and I'm very experienced with electrical work.
Cleaned the MAF
After problem persisted I cleaned the contact surfaces inside the throttle pedal.
Replaced the air filter, found a mouse nest in the airbox below the filter, damn mice!!!! Replaced a few vacuum lines as they we looking a little gummy and dryrotted.
Replaced the spark plugs recently as they were around 20-30k miles old
Took it to a shop where we discovered the additional codes that my standard reader did not see.
Ordered a VIDA scanner but that hasnt arrived yet. When it does I plan on doing the ETM sweep test.

[abscate]

Replaced the TPS with a Sacer unit but did not set the voltage as I only found this info after the replacement and continued problem.

I believe this is an important step.

[JeremyXR]

I agree with you but I would not expect the voltage calibration to cause an intermittent fault. Forgot to mention that I also cleaned the throttle body when I replaced the TPS.

[Polibon]

Hi Jeremy, did you get to the bottom of your problem, because I have almost exactly the same scenario. I have a 2000 V70 (non-turbo though) with 190k miles on the clock and the idle has been getting more erratic - although it was only an issue after the engine was fully warm, after about an hour of driving. Today I fitted a new Sacer unit in my ETM and as an ex biomedical engineer, I feel I have done a respectable job, although like you I did not know about the voltage tests; and still don't know what to look for, so if you have some instructions please could you share them with me. Many thanks, Paul