No, the throttle body has a much longer life expectancy than the TPS unit. Of course, if there is a bad part in the throttle body, or some other problem; then it would require replacing. But given regular cleaning, Metro throttle bodies are very long lived. How do you know that the TPS needs replacing? These parts are sometimes misadjusted (along with the throttle stop screw and idle air bypass screw) by misinformed people, which could make it seem like the TPS was bad, when it really wasn't. Also, where do you plan to buy a TPS unit. The dealership may charge a fortune for it; but you can buy a Standard Motor Products # TH148 (which is the correct part for the 2000 3 cylinder Metro) from www.rockauto.com for $128.99 plus shipping. This part has the same type of label as the original; so I expect it is sourced from the OE manufacturer.
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