Volkswagen P1136: Fuel Trim Additive Lean (B1) — Fix
On Volkswagen vehicles, P1136 means the additive (idle) fuel-trim system on bank 1 is at its lean limit — the engine runs lean, especially at idle.
- Applies to
- Volkswagen vehicles
- Est. repair cost
- $40 – $500
- Time to fix
- 30 minutes – 2 hours
What it means
Causes include an intake/vacuum leak (often at idle), a dirty MAF, or an injector/fuel-delivery issue. P1xxx codes are manufacturer-specific — P1136 is defined by Volkswagen (not part of the generic SAE J2012 set), so this definition applies to Volkswagen vehicles. Model years can vary, so confirm against the Volkswagen service manual. Fix the fault, then clear the code with a scan tool.
Symptoms
- Check engine light on
- Lean-related rough idle
- Hesitation off idle
How to fix it
- 1
Smoke-test for idle vacuum leaks
1. Look for intake leaks that show up at idle. 2. Clean the MAF.
- 2
Check fuel delivery
1. Test fuel pressure and injectors. 2. Repair, then clear the code.
Frequently asked questions
Difference between P1128 and P1136 on a VW?
Both are lean fuel-trim faults on bank 1 — P1128 is the multiplicative (load) trim, P1136 the additive (idle) trim. An idle vacuum leak often sets P1136.
Last updated July 19, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.