What are the common issues with the 1979 Porsche 911 Turbo's engine and maintenance costs?

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The ’79 930 Turbo is bullet-proof *if* you stay ahead of a few well-known issues:

Common engine problems
• Chain-tensioner failure (pre-'83 cars still have the spring style) – can skip timing
• Turbocharger oil-line leaks or cooked bearings from heat soaking after shut-down
• CIS injection: hard-start/rough idle when fuel distributors or warm-up regulators clog
• Valve-train: 930 needs a manual valve adjust every 15k mi; exhaust valves tighten with age
• Oil cooler seals & return tubes—weeps oil onto the heat exchangers, smells like burning oil
• Head-stud cracks on earlier 3.0s are rare on ’79 3.3, but still worth an inspection

Typical 2025 U.S. shop costs (labor $150-180/hr, OEM or quality aftermarket parts)
• Valve adjust: $1 200 – 1 500
• Chain-tensioner upgrade to later hydraulic style: $1 800 – 2 200
• Turbo rebuild (stock KKK): $2 000 – 2 500; new CHRA adds ~$1 000
• CIS full service (new injectors, fuel head re-seal, WUR): $1 400 – 1 800
• Oil cooler seal kit + return tubes: $900 – 1 200
• Annual engine-bay re-fresh (fluids, plugs, filters, valve-cover gaskets): $700 – 900

Budget rule of thumb: plan $2 000–2 500 per year in normal miles, and set aside $5 k cushion for the occasional turbo or bottom-end refresh. Porsche Classic shops know these cars, so the one you’re looking at in St. Louis should already have the big-ticket items sorted—still smart to ask for the service file.

Lot P09800318: 1979 Porsche 911 Turbo

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Lot P09800318: 1979 Porsche 911 Turbo

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