* Exhaust Leak Near Engine: If the new exhaust system wasn't installed perfectly, there might be a leak near the engine. This could draw in oil fumes or even allow oil to leak into the exhaust system, leading to the smoke. Check carefully for any leaks, especially around the manifolds and gaskets.
* Damaged Valve Seals or Worn Piston Rings (Coincidence): The timing of the smoke and the exhaust installation is probably coincidental. The engine might have developed a problem with worn valve seals or piston rings which are now manifesting as smoke *after* the exhaust was installed. The new exhaust might just be making the existing, small amount of oil burning more noticeable.
* Improperly Installed Catalytic Converter (If Applicable): If your van had a catalytic converter, and it's part of the new exhaust, improper installation could restrict exhaust flow. This could lead to a buildup of pressure and force oil past seals, causing smoke.
Troubleshooting Steps:
1. Inspect the Exhaust System: Carefully examine the entire exhaust system for leaks. Look for soot, oil stains, or any visible damage. Pay close attention to the connections near the engine.
2. Check the Oil Level: Is your oil level low? Low oil level is a strong indicator of oil burning. Check it frequently.
3. Check the Oil for Contamination: Is the oil milky or unusually dark? This could indicate coolant leaking into the oil (head gasket problem).
4. Observe the Smoke: Does the smoke get worse under load (accelerating)? Or only at idle? This can help pinpoint the source. Bluish-white smoke is more indicative of oil burning than pure white (coolant) smoke.
5. Compression Test: A compression test can help assess the health of the engine's cylinders and rings.
If you're not comfortable performing these checks, take your van to a trusted mechanic. It's unlikely the exhaust system itself is the *direct* cause, but it could be indirectly related or the new exhaust is highlighting a pre-existing issue.
