Skip the auto shop - Our mechanics make house calls

Q: Error code P0171 and P0374

asked by on

I used the OBD II / EOBD CODE READER and found the following code P0171 System too lean Bank 1 (Generic o) P0374 Timing Reference Hig n Resolution Signal A No Pulses (Generic o) P0171 System too lean Bank 1 (Gen Pd o) P0374 Timing Reference Hig n Resolution Signal A No Pulses (Gen Pd o) Freeze Frame: DTCFRZF P0171 Fuel sys 1 CL Fuel sys 2 -- Load_PCT (%) 75.29 ECT( ‘C) 78.00 SHRTFT1 (%) 0.00 LONGFT1 (%) 25.00 SHRTFT2 (%) 0.00 LONGFT2 (%) 25.00 MAP (kPa) 47.00 RPM(rpm) 705.50 VSS(km/h) 0.00 SPARKADV 4.5

I don’t feel anything while driving the 2006 Ford Five hundred SEL (I don’t have much knowledge about vehicles), It accelerates well and goes easily to 40miles per hour when given the acceleration (I have not tried beyond 40 miles/hr in order to avoid any damage, as I bought it recently and want to repair it before use) the odometer reads about 200,000 miles, I showed to a local mechanic he said the gear is either in 2nd or 3rd (limp mode) after a short test drive???

My car has 200000 miles.
My car has an automatic transmission.

Hi and thanks for contacting YourMechanic. If the vehicle went into limp mode, then the computer is making this happen to prevent the engine from any damage. Check the camshaft sensor for proper timing to the camshaft. Look at the harness and make sure that it is plugged in and free from any moisture. Since the engine is running good, the crankshaft sensor is working correctly. Disconnect the camshaft sensor and drive the vehicle around to see if there is any change to the performance of the engine.

If there was no change, then the camshaft sensor needs replaced. If it did change then, you will need to check the timing of the engine with a timing light. When checking with a timing light, make sure that the timing flash is on the same point. If the timing is not at the same point, then the engine will need a timing chain and / or tensioner. If the timing is steady, then the camshaft sensor needs replaced. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can assist you with the engine codes coming up.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: I'm having problems with code po740

Hi there. In order to be able to give you more exact information I would need to know whether or not the vehicle is equipped with the CVT transmission. It sounds like you have the regular transmission in your vehicle....

Q: Could this be the TCM causing the problem?

Yes, no start in the scenario you are describing is possible especially if Code U1000 has set, along with other codes such as P0717, but there are multiple code scenarios or combinations. One quick strategy is to pull and visually...

Q: I have a Po171 code on a 2006 trailblazer

The cause behind diagnostic trouble code P0171 is easiest to find by looking at the secondary firing patterns on the Bank one cylinders. That will confirm if the too lean condition, that has caused the code to set, affects all...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...