A 1998 Chevy Tracker, equipped with a 1.6L 16V automatic engine, won’t start after a transmission swap from a 1996 Geo Metro. The engine cranks but doesn’t fire, and a scan reveals a P0335 code: Crankshaft Position Sensor (CKP) Circuit Malfunction. Further inspection reveals the engine lacks a CKP sensor, the corresponding sprocket (reluctor wheel) behind the crankshaft pulley, and the necessary oil pan opening for the sensor. This raises the question of whether the engine is from a pre-1996 Geo Metro, potentially explaining the missing components. The core issue is determining compatibility and the feasibility of retrofitting the necessary parts.
Identifying the Problem: Missing CKP Components
The P0335 code points directly to the crankshaft position sensor circuit. However, the physical absence of the sensor itself, along with the reluctor wheel and oil pan opening, indicates a more significant problem. These parts are essential for the engine management system to determine crankshaft position and timing, critical for spark and fuel delivery.
The image above shows the timing cover removed, revealing the absence of the reluctor wheel behind the crankshaft pulley. This wheel, with its teeth, generates the signal the CKP sensor uses to determine engine speed and position.
This image illustrates the correct configuration with the reluctor wheel installed. The difference is stark, highlighting the missing component in the problematic engine.
Is it a Pre-96 Geo Metro Engine? OBD1 vs OBD2
A crucial question is whether the current engine is original to the 1998 Chevy Tracker or if it’s a pre-1996 engine from the donor Geo Metro. 1996 was a transition year for emissions standards, with vehicles switching from OBD1 (On-Board Diagnostics 1) to OBD2. This transition often involved changes to engine management systems, including sensor types and locations.
Geo Metros from 1995 and earlier used OBD1 systems, while 1996 and later models used OBD2. A visual inspection of the diagnostic connector can confirm whether the vehicle is OBD1 or OBD2. OBD1 connectors typically have fewer pins and a different shape than OBD2 connectors. If the Tracker has an OBD1 connector, it strongly suggests a pre-1996 engine swap.
Potential Solutions: Retrofitting the CKP System
If the engine is indeed a pre-1996 model, retrofitting the CKP system might be possible. This would involve:
- Installing the Reluctor Wheel: This requires removing the crankshaft pulley and timing belt, potentially necessitating specialized tools. Clearance issues might arise if the crankshaft of the older engine doesn’t accommodate the reluctor wheel.
- Replacing the Oil Pan: A new oil pan with the correct opening for the CKP sensor is required. Modifying the existing oil pan is not recommended due to potential sealing and reliability issues.
- Installing the CKP Sensor: Once the reluctor wheel and oil pan are in place, the CKP sensor can be installed and connected.
The image above highlights the lack of a sensor hole in the existing oil pan, further reinforcing the need for replacement.
Conclusion: Assessing Feasibility and Sourcing Parts
Before proceeding with the retrofit, carefully measure the crankshaft to ensure sufficient space for the reluctor wheel. Consult service manuals for both the 1998 Chevy Tracker and the 1996 Geo Metro to confirm compatibility and identify the correct parts. Sourcing parts from a reputable supplier like Parts Dinosaur or a salvage yard specializing in Geo Metros is crucial. Successfully retrofitting the CKP system could potentially solve the no-start issue, but careful planning and execution are essential. If the retrofit is not feasible, engine replacement might be the only viable option.
