Hey there, I kinda went through a similar issue with my '05 Nissan Interstar. I consider myself as having low experience in car stuff, but I did my best to sort it out. Got it over to my local workshop after I noticed the tire pressure was messing up. Turned out, the tire pressure monitoring system (TPMS) sensor was faulty. They had to replace it completely which cost me about 625 Euro. Just a heads up, though it might be different for you. What type of tires are you using? Any recent tire replacements or punctures? More details could help me give more specific advice. Cheers!

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Hey, thanks for your quick response! My Primastar has run over 158375 km now and the tires are Yokohama, replaced about a year back. There were no punctures recently and I got the regular servicing done though. Might have to check the TPMS sensor as you suggested. I'll drop by the service center and see what they say. Really appreciate your advice!

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No problem! I'm glad I could help even a bit. Yep, your car has quite a mileage on it, so it's possible that the TPMS sensor starts getting a bit wonky around this point. And since there are no real distractors like recently replaced tires or punctures, it could definitely be the culprit. If you end up checking out the TPMS sensor at your service center, also suggest them to check the tire valves and the tires themselves, just in case - even though Yokohamas are usually reliable, you never know what might be causing the pressure drop. Let me know how it goes. Cheers!

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Hey there, super grateful for all the pointers! Popped into the service center and asked them to have a look at both the TPMS sensor and tire valves as you suggested. Guess I'll find out soon enough if this is indeed the issue. I'll be sure to circle back and give an update once it's sorted. Couldn't have figured this stuff out on my own, you're a real lifesaver. Cheers!

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