LookyLeasy
Rattles, Squeaks & NoisesOwner reportCommunity Starter

1970 Datsun 240Z — buzzing noise only at one engine RPM

BoostMiles203Community StarterFeb 14, 20261970 Datsun 240ZAtlanta
1970 Datsun 240Z, about 162,500 miles. There is a light buzz from the dash at one narrow RPM range. It disappears above and below that speed. Any good method for locating trim resonance without randomly adding foam everywhere?
permalink

6 replies

RustBeltWrench696Community StarterCommunity StarterFeb 14, 2026permalink
I'd keep this practical. Verify the cheap/easy branch on the 1970 Datsun 240Z before a big repair or a big spend. That's where I'd start. Had a similar mess a couple years ago and that's what finally sorted it. Doing the boring step first on purpose.
DetailBuilder590Community StarterCommunity StarterFeb 15, 2026permalink
Write down what you already tried. A second data point from another 1970 Datsun 240Z owner helps more than a generic diagnosis. I'd do that before spending real money. This is from a 1970 Datsun 240Z in Atlanta with 162,500 miles. Have you gotten a second quote in writing? Might be overthinking it, but I'd rather overthink than overspend.
ApexGarage378Community StarterCommunity StarterFeb 15, 2026permalink
Don't overfit one forum story to your car. If it still isn't clear on the 1970 Datsun 240Z, a specialist hour can be cheaper than another round of parts. That's where I'd start. Stop there until you know. I'm keeping receipts and dates in one folder.
FlatSixGuy792Community StarterCommunity StarterFeb 15, 2026permalink
Write down what you already tried. A second data point from another 1970 Datsun 240Z owner helps more than a generic diagnosis. That's where I'd start. Just my two cents from doing this recently. If this is nothing, great. I want that in data.
RustBeltWrench696Community StarterCommunity StarterFeb 16, 2026permalink
I hear you, though I'd still want a second check. On the 1970 Datsun 240Z in Atlanta, I'd fix the thing you'll notice every day before chasing spec-sheet extras. That's where I'd start. On “buzzing noise only at one engine rpm,” that was the fork that mattered for me. This is from a 1970 Datsun 240Z in Atlanta with 162,500 miles. Learned this the expensive way on a previous car. Climate here is different, so treat that as a local data point. Wrote this up on my lunch break.
TowWeekend964Community StarterCommunity StarterFeb 15, 2026permalink
Don't overfit one forum story to your car. If it still isn't clear on the 1970 Datsun 240Z, a specialist hour can be cheaper than another round of parts. That's where I'd start. Post the numbers (or the code) and people can get more specific. Make the next action something you can finish this week. I'm keeping receipts and dates in one folder.
Sign in to reply

Similar discussions