RWG Voltage High: No Gas Intake - Help!

Hello everyone,

First of all, I would like to warmly greet you all and thank you for the numerous helpful suggestions you have already provided.

I drive a Volkswagen Passat 1.9 TDI with 66 kW (engine code 1Z) and I was experiencing the well-known jerking sensation under partial load. After extensive troubleshooting, I decided to verschandeln the MSW (Mass Air Flow Sensor) as described in your technical article.
At this point, many thanks to the authors of the article .
I made a mistake (I'm really not a professional): I marked the pump with "MSW" instead of marking the "MSW" cover and the "MSW" lower body . Unfortunately, I don't have a VAGCOM.
So, I didn't read any values (voltage at the RWG sensor, etc.), but instead, I photographed the RWG using a digital camera. After the initial assembly, the car ran for a week, then it stopped working. Everything was disassembled, and the solder joints were loose. I re-soldered them, applied the MSW to the ESP, aligned it (as best as possible), and test drove it.

After approximately 25 km of driving, there was extremely strong jerking during acceleration. The car then stalled and would not restart. There is no throttle response; the engine only starts when the multi-spark ignition system is adjusted (tapping helps). No throttle response, nothing .


A friend of mine said it wouldn't be a problem; he would bring his laptop and VAGCOM interface and help me adjust the RWG sensor to 0.740V (not in idle, but with the ignition on), and later, as he claimed, adjust the injection quantity to approximately 6 mg per stroke.

Okay, we've set the RWG to 0.740, but the car isn't responding at all when I try to accelerate. When I moved the MSW on the ESP and the engine was running at around 1000 RPM for about 5 minutes, it still wouldn't respond. Then, my friend told me that the voltage at the RWG is constantly stuck at 5.1V and won't go any lower, even when only the ignition is turned on.
Could you please tell me what's causing this? (P.S. The battery was weak, which might be relevant, and a valve is constantly making a clicking noise like a woodpecker – the solenoid valve, which I've already replaced).
He said that the error with the rule path generator keeps recurring in the software (Error 765: Sensor for control slide position). We have repeatedly disconnected and moved the RWG, but nothing happens; the voltage does not decrease .

What should I do?
Please help me; it's winter, and I need the car (I know that wasn't a smart strategy, but that's just how it is now ).

Thank you very much and best regards.
MaliDavid

I can reassure you about the valve.

The blow-off valve is always making noise; it's the N75 (boost pressure control valve) and it's located on the Passat near the firewall, essentially extending from the speedometer.

Unfortunately, I've only disassembled mechanical pumps so far, so I can't really contribute anything constructive to the discussion about the MSW (presumably referring to a specific machine or system).

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Hello Dieselmartin,
Thank you for your reply.
I have already read some of your posts, and they are always very constructive .

I think the turbocharger boost valve isn't the problem either. I'm just not entirely sure how it works when you connect the MSW (Multi-Sensor Wheel) to the ESP (Electronic Stability Program), since I don't have a VAGCOM diagnostic tool. Can you feel that the MSW is difficult to move if the camshaft is in the bore?

Well, I have the feeling that the more electronics there are, the more difficulties...

I used to have a Golf II GTD with 400,000 kilometers on the clock; that car just kept running and running.

Back to the topic:
Okay, I don't understand why this voltage remained the same, even when the RWG was loosened and moved.

Very important:
After we had set the RWG to 0.740 V and wanted to perform a test as described in the technical article (turning on the ignition), the RWG only moved about one-third of the way. It should actually go all the way to its limit, right?

Once again, thank you, Dieselmartin. Other contributions are welcome and equally appreciated .

malidavid wrote:

Does it feel like the MSW is difficult to move when the cam is in the hole?

No, unfortunately not at all. I always positioned the ring manually based on feel, put the MSW on and off several times (for practice), and assumed that if the ring didn't move, I had hit the correct spot for drilling.

However, it could be a good way to check if you missed the hole, or if one of the solder points is causing an issue.

Hello Wolfi,
Thank you for your reply. Setting up the MSW always costs a few gray hairs , because it's simply almost impossible to apply a system to it. Your approach seems to be the only sensible method.
Do you perhaps know why the voltage didn't drop, even though I subsequently disconnected the MSW from the ESP and only connected the MSW to the car's circuit with the cable? I repeatedly detached and moved the RWG, but the voltage remained at 5.1 V. Does the control unit have a constant pulse (if you can call it that)? Could this indicate a problem with the solder joints?
Thank you for your and all the answers, and best regards .
MaliDavid

malidavid wrote:

Does this indicate a soldering joint issue?

I think so, why don't you just check? It seems like you don't have much experience with soldering. If I were you, I would let someone who is good at it do the soldering, especially in such a critical area! Keep in mind what could happen if a solder joint fails suddenly while you're driving!

Hello Wolfi,
Thank you for your tips.
Yes, it's true; I don't have much experience with soldering irons, so I think it could very well be a cold solder joint. Unfortunately, I don't have anyone here who can help me, at least not someone who really knows how. I haven't lived here for very long and barely know anyone.

What happens if such a solder joint fails? Sorry, it might sound like a stupid question, but I'm not an expert .
Best regards,
MaliDavid

Hello everyone,
Okay, I've done it. / There you have it. / And now I've finally managed it.
The shaking is gone, the car drives wonderfully, and the values are optimal. I would like to thank you all for that, and also to everyone who has contributed here.

The problem was probably the MSW connector, which wasn't properly seated. So, I disconnected the battery and let it charge overnight.

After that, I cleaned and reassembled the MSW completely according to the instructions. It is very important that you follow everything exactly as it is described. Excellent description here in the forum!!!

If, as happened in my case, you mess something up, meaning either the position of the MSW on the ESP or the position of the RWG within the MSW is misaligned, you can only fix it using VAGCOM software. Then, you need to adjust the voltage value with the ignition turned on and subsequently position the MSW on the ESP. Finally, set the fuel injection amount, and that's it (note that when the engine is cold, a little more fuel is drawn in ). (There's an excellent table here in the forum for the values).

@Rainer Kaufmann -> merci for tolerating the topic in the wrong place; the karma thing is a bit unusual always stay friendly .

@Wolfi, Martin, and everyone else -> thank you very much for all the tips, your patience with the repeated questions, and your willingness to help.

I intentionally wrote a bit more and also wanted to report the final result, because there are numerous threads all over the internet (including here ) that are temporarily discussed but never fully debated. I hope it will be a small help for those who read this later .