U0105 — Lost Communication With Fuel Injector Control Module
U0105 — Lost Communication With Fuel Injector Control Module. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: weak fuel pump or clogged fuel filter, clogged or leaking fuel injectors, contaminated or incorrect fuel.
vehicle network
Is it safe to drive?
Drive with caution Drive with caution. Mixture and fuel-pressure faults can cause stalling, hesitation in traffic and — when severe — catalyst damage. Avoid long trips until diagnosed.
How to diagnose with an OBD scanner
- Read the code and freeze frame Connect an OBD2 scanner, confirm U0105 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many U0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the fuel delivery and mixture control for damage, corrosion, chafing or poor contact.
- Subsystem check Measure fuel pressure at the rail and compare with factory specification at idle and under load.
- Subsystem check Check short-term and long-term fuel trims in live data to see which way the mixture is off.
- Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm U0105 does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for U0105 (parts and labor, USD, independent shop rates): Replace the fuel pump: $400–$900; Replace the fuel filter: $80–$200; Replace the pressure regulator or sensor: $150–$450; Clean or replace injectors: $200–$800. Overall, fixing U0105 usually costs between $80 and $900. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Common questions
Will U0105 clear itself?
Sometimes U0105 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.
How much does it cost to fix U0105?
Replace the fuel pump — $400–$900; Replace the fuel filter — $80–$200; Replace the pressure regulator or sensor — $150–$450; Clean or replace injectors — $200–$800. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
How do I diagnose U0105 myself?
Start with a scan: confirm U0105, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the fuel delivery and mixture control, and verify the suspect component against live data before buying parts.
What are the symptoms of U0105?
Drivers most often notice: fuel smell in severe cases, loss of power under load, rough idle and hesitation, increased fuel consumption.
What is the most common cause of U0105?
The most common causes are: weak fuel pump or clogged fuel filter, clogged or leaking fuel injectors, contaminated or incorrect fuel.
What does U0105 mean?
When U0105 appears on a scan, it means the control module has flagged a problem in the fuel delivery and mixture control: lost communication with fuel injector control module. The fault sits in the vehicle network group of the OBD2 standard.
To set U0105, the control module compares live readings of the fuel delivery and mixture control against calibrated limits, usually over several drive cycles. Alongside the code it stores a freeze frame — a snapshot of rpm, load, coolant temperature and vehicle speed at the moment of failure. Reading that snapshot first saves diagnostic time.
What causes U0105?
- clogged or leaking fuel injectors
- faulty fuel rail pressure sensor or wiring
- vacuum or intake leaks skewing the mixture
- weak fuel pump or clogged fuel filter
- contaminated or incorrect fuel
Common symptoms of U0105
- fuel smell in severe cases
- loss of power under load
- rough idle and hesitation
- increased fuel consumption
- hard starting or long cranking
- Check Engine Light on
How to diagnose U0105
- Connect an OBD2 scanner, confirm U0105 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many U0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Visually inspect the wiring harness and connectors related to the fuel delivery and mixture control for damage, corrosion, chafing or poor contact.
- Measure fuel pressure at the rail and compare with factory specification at idle and under load.
- Check short-term and long-term fuel trims in live data to see which way the mixture is off.
- Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm U0105 does not return.
How to fix U0105
Start with the cheapest and most common causes before replacing expensive parts:
- Replace the fuel pump — $400–$900
- Replace the fuel filter — $80–$200
- Replace the pressure regulator or sensor — $150–$450
- Clean or replace injectors — $200–$800
How much does it cost to fix U0105?
Repair cost depends on which component actually failed. Typical scenarios for U0105 (parts and labor, USD, independent shop rates):
- Replace the fuel pump: $400–$900
- Replace the fuel filter: $80–$200
- Replace the pressure regulator or sensor: $150–$450
- Clean or replace injectors: $200–$800
Overall, fixing U0105 usually costs between $80 and $900. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Can you drive with U0105?
Drive with caution. Mixture and fuel-pressure faults can cause stalling, hesitation in traffic and — when severe — catalyst damage. Avoid long trips until diagnosed.