2006 Chevy Express 3500

Wonderful van, I love it, but have an issue that the repair shops can’t solve. Vehicle surges, hesitates, stalls, backfires, and is hard to start after stalling.
No codes are thrown, and have had the fuel system checked out without results. 159.000 miles. last mechanic said it was not a spark plug issue. Been an ongoing problem for several months and getting worse all the time.

Many possible causes including:

Vacuum leak
Dirty throttle body (have it checked/cleaned)
Faulty throttle position sensor (TPS)
Dirty/faulty idle air control valve (IAC)
Dirty/faulty mass airflow sensor (MAF)

Find a recommended local mechanic in the Mechanics Files section of this site. Evidently your “last mechanic” does not know how to diagnose this. Find someone who does.

With 159,000 miles on the engine, has anyone checked for a worn timing chain?

Tester