Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1998 Volvo S70 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Turbocharger Control Valve Control
- Start engine. Using scan tool, go into scrolling values. Accelerate hard several times and watch parameter TC CONTROL. If parameter constantly exceeds 90 percent, go to next step. If parameter does not constantly exceed 90 percent, check ECM power and ground circuits. See ELECTRONIC CONTROL MODULE (ECM) .
- Turn ignition off. Check hose between turbocharger control valve and fresh air intake for blockage or damage. Check nipples on turbocharger control valve and fresh air intake for blockage. Repair as necessary.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.