C30 Electrics : C30 throttle body calibration?

[Popeye253]

Hello. I have recently bought a 57 plate C30 1.8 petrol. On the test drive it drove spot on, and after buying the car (private sale so no warranty) it drove great on the way home. The next day it started stalling at low revs at lights etc. Thinking it was something to do with the fuel because it was stood for a wile. I checked and no problems with the fuel. After taking the car to the garage they said it was the throttle body. Taking the car home and cleaning the throttle body it was doing the same thing. Now after replacing the throttle body with a new one its doing the same and now showing reduced engine power on the display, with the engine light on. I plugged in a code reader it was saying throttle position stuck open. After asking the garage they said the throttle body/position might need calibrating. After looking online and not really finding anything on how to do this. I found one video saying start the engine and let it run for 15 minutes to let the car calibrate its self. Now the display is saying the throttle position stuck closed!. So please if anyone knows how to calibrate the throttle body/throttle position. Can you please run me through the process please. Thank you

[Simmy]

throttle body can warp if its over tight on the screws try backing off some of the tension on the screws it dosent need to be over tight just enough to make a seal

[passenger]

Well some advamce diagnostic tool will do it. I have NT650 foxwell and VIDA. I did it VIDA in 3min. Not sure is there any other way to do it (manually)

[MatejBinka]

Originally Posted by Popeye253

Hello. I have recently bought a 57 plate C30 1.8 petrol. On the test drive it drove spot on, and after buying the car (private sale so no warranty) it drove great on the way home. The next day it started stalling at low revs at lights etc. Thinking it was something to do with the fuel because it was stood for a wile. I checked and no problems with the fuel. After taking the car to the garage they said it was the throttle body. Taking the car home and cleaning the throttle body it was doing the same thing. Now after replacing the throttle body with a new one its doing the same and now showing reduced engine power on the display, with the engine light on. I plugged in a code reader it was saying throttle position stuck open. After asking the garage they said the throttle body/position might need calibrating. After looking online and not really finding anything on how to do this. I found one video saying start the engine and let it run for 15 minutes to let the car calibrate its self. Now the display is saying the throttle position stuck closed!. So please if anyone knows how to calibrate the throttle body/throttle position. Can you please run me through the process please. Thank you

Popeye, did you solve the problem with calibration? I am experiencing totally identical problems, stalling and bad throttle response with original ETB and codes of throttle actuator stuck open with the aftermarket ones.

[jengvalljr2]

I've got plenty of awful vehicle stories and have solved most of them myself, but this one has literally kicked my ass.

12/10/22 I floored it while entering the freeway and got a "Reduced Engine Performance" error and indeed it was reduced.

Originally, it spit out many codes, some of which were CEM related and ECM related; ECM codes were 922D, 921D, 850D, 290B (fuel pressure), and long ago -- December 2022 at early stage.

Have codes p2135 and p0638 -- which in English means a bad throttle body position sensor or accelerator position sensor.

I have replaced both.

Twice (once with aftermarkets and once with Bosche/Volvo OEM), with no improvement.

Over the past 12 months.

I do NOT have VIDA but the mechanic I took it to in 2022 does have VIDA; replaced fuel filter and cleaned leads to CEM and/or ECM, because I told him try the cheapest thing first -- which is to say I am not blaming him.

After the car left me stranded literally the next day on Loop 610 in Houston -- with cars going by my at 80mph, I tried replacing the throttle body (which comes with the sensor as part of it) AND the throttle pedal (which also comes with the sensor; tried aftermarket and then OEM Volvo used pedal and throttle body from Erie Volvo -- one of best sources or used Volvo parts in the country.

Result?

Same codes, same dangerous engine performance, surging, sputtering and not being able to drive more than 15 mph.

Gave my son my car and I'm driving my old Rover -- separate nightmares, but hey, at least those are on the brochure and expected from the historically most UNreliable vehicle on teh planet.

Bottom line, I let the car sit for the last 11 months and I really don't want to spend thousands getting it to run reliably.

Please offer suggestions and/or humor if you have any.

Also, I have read literally dozens of threads on dozens of sites, including this one, and here are questions I have:

1. Does anyone really know whether the throttle bodies on T5 engines newer than say 2001 or 2002 have to be "calibrated" or is that only on the older ones?

2. Is Xemodex the most affordable next step -- maybe spend the $500 or $600 bucks to make sure the ECM and/or CEM isn't fubarred?


3. Some non-volvo threads have suggested limp mode can be caused by plugs or coils going bad - but not seeing any Volvo chains on that.

Should I try that as a cheap dart at the board?

4. Have not replaced PCV system -- I bought this C70 (my second one) with 78k miles on it and it has 99k now.

Should I they that as a cheap dart at the board?

Thanks in advance for any help or humor you can provide.

[Georgeandkira]

I'd go with the Xemodex rebuild.
You're correct in not firing the parts cannon (coils/plugs) at this.
Inspect 'em (no big deal) as you never know.

Try a balloon over the dip-stick tube or pressed against the oil fill for a PCV functionality test.