Where is the o2 sensor for a 1999 dodge grand caravan?

The location of the O2 sensor(s) on a 1999 Dodge Grand Caravan depends on the engine. There's typically one upstream (before the catalytic converter) and one downstream (after the catalytic converter).

To find the exact location, you'll need to:

1. Determine your engine: Check your vehicle's paperwork or the sticker inside the driver's side doorjamb. Common engines for that year include the 3.3L and 3.8L V6.

2. Consult a repair manual: A Haynes or Chilton repair manual specific to your 1999 Dodge Grand Caravan and engine will have diagrams showing the exact location of the O2 sensors. This is the most reliable method.

3. Use an online parts diagram: Many auto parts websites (like AutoZone, Advance Auto Parts, etc.) allow you to enter your vehicle's information and view diagrams showing the sensor locations. Be aware that these diagrams might not be perfectly accurate for all variations of that model year.

General Location Hints (but always verify with a manual or diagram):

The upstream O2 sensor is usually located in the exhaust manifold or very close to it, while the downstream sensor is closer to the catalytic converter. They're typically threaded into the exhaust pipe. They often have wiring harnesses connected to them. Be careful when checking as the exhaust system gets very hot.

Without knowing the exact engine, I cannot provide a precise location. Using a repair manual or an online parts diagram specific to your vehicle's engine is crucial for accurate identification.