2004 Dodge Caravan P0016, P0335b, P0339 Fault: Sensor Replacements Failed, Timing Chain or Electrical Issue?
I recently encountered recurring engine fault codes on my 2004 Dodge Caravan: P0016, P0335b, and P0339. Initially, the issue was diagnosed as a camshaft position sensor — I replaced it, but the problem returned after one week. The second diagnosis pointed to a crankshaft position sensor; after replacement, symptoms reappeared two weeks later. After multiple visits, the vehicle now shows both P0016 and P0335b/P0339 codes. Since replacing both sensors did not resolve the issue, I suspect it's not a sensor failure. My mechanic ruled out a timing belt — noting that the van ran fine for several weeks between issues. However, the vehicle has over 200,000 kilometers on the odometer and is now causing significant daily transportation disruptions. I'm concerned about whether I should replace the ECU or risk costly engine disassembly to replace a timing chain (which my mechanic says isn't necessary). The van runs normally when codes are cleared by disconnecting the battery, but shortly after, symptoms return — including rough idle, stalling, and rev limit issues. I'm seeking advice based on real-world experiences with 2004 Dodge Caravan models and these specific fault codes. I want to avoid unnecessary ECU replacement or overhauling engine components without solid evidence. Any insights into common root causes — such as electrical faults (e.g., bad ground, corroded wiring), sensor quality differences, or timing chain wear — would be greatly appreciated.
Timing belt? What engine size is in your van? A 3.3L or 3.8L doesn't have a timing belt — both use timing chains. The 2.4L 4-cylinder does have a belt. Which one do you have? Also, what brand of cam and crank sensors were installed? Are the original sensors still in place? If it's a 2.4L with over 200,000 km on the original belt, consider replacing it — even if it seems to be running fine, it may fail unexpectedly and cost significantly more later.