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P0178 check engine light is on code is P0178 what do I need.

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I want to buy and replace sensor p0133, p1401, and p0176

p0133, p141 and p0176 - those are fault codes

Go to this site:

Engine and OBD Diagnostic Codes

Feb 08, 2014 | 1996 Volvo 960

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Will someone please tell me what code numbers 700 and 178 mean? It's for a 2005 Suzuki Forenza Wagon.

can you tell us what told you that.
1: autozoned
2: your car dash
3: your scan tool?

if a real scan tool it will show, P0700
p0 means federal std. codes....

P0700 Suzuki - Transaxle Control System Malfunction
P0178 i cant find. please post full numbers and letters. all count

this engine is hard to work on
its a Frankenmix car, Suzuki, Daewoo, GM-Holden mix.
my wild guess it has GM engine controls, so getting good info is hard.
but is at , log in see diagnostics section for codes.

Dec 28, 2013 | 2005 Suzuki Forenza Wagon

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Po178 po179

codes p0178 and 179 refer to fuel composition sensor--low and high input respectfully==causes for 178 are wiring--- short to ground--fuel composition sensor--ECM and for 179 are wiring short to positive-- fuel composition sensor---ECM

Dec 06, 2013 | Cars & Trucks

1 Answer

Reset check engine light

need code scanner but first find what causes check engine light to turn need to code scan find what code you are getting fix bad sensor.then use code scan to erase code.if you dont fix problem will check engine light will stay on.

Dec 28, 2012 | 1999 Ford Explorer

2 Answers

How to reset engine lite in dash

Check engine light comes on and off, these are indication that there is some error code stored in your vehicles ECM. The engine module computer needs to be scanned. These will give the code and as per the error code the further problem can be detected and confirmed. The engine light indicator blinks or remains steady on dash when engine computer noticed any problem with any engine electrically operated components.

For more help, I suggest you to refer the help links provided below. These will let you know more about which areas to look, check, when there is engine light coming up on dash panel.


Click the link below: -------

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These details will help.


Nov 28, 2012 | 1999 Acura CL

1 Answer

2000 chevy s10 wont keep running many scan codes

Your truck has an antitheft system called passlock. It runs thru you bcm. When this system fails, your truck will start for 1-5 seconds and then stall. The fuel enable is switched off, and injectors fail to squirt. This may be your problem and is a "bypassable" problem. This link explains.

May 17, 2012 | Cars & Trucks

2 Answers


This is a failure code for a fuel composition sensor and man are they proud of these sensors. Last time I put one on the price for the sensor was almost 500.00. This does usually not cause a driveability problem. Here is a circuit description

Alcohol content and fuel temperature information is supplied to the powertrain control module (PCM) from the fuel composition sensor (FCS). The FCS has an ignition 1 circuit, a signal circuit, and a ground circuit. The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel temperature, and changes output signals accordingly. The signal circuit carries both the ethanol percentage, and the fuel temperature within the same signal. The signal is both variable frequency and variable pulse width. The frequency signal indicates the ethanol percentage, and the pulse width indicates fuel temperature. The PCM provides an internal pull up to 5 volts on the signal circuit, and the FCS pulls the 5 volts to ground in pulses. The normal range of operating frequency is between 50-150 Hz. The normal pulse width ranges between 1-5 milliseconds. If the PCM detects a signal less than 45 Hz DTC P0178 will set.

Your stall when put in gear is most likely due to a dirty throttle body (carbon build up). Remove the air intake tube to the throttle body & use a spray can of carb spray & a shop towel to clean the carbon from the throttle bore & plate.

Fuel Composition Sensor Replacement - Removal Procedure
Turn OFF the ignition.
Relieve the fuel pressure


Raise the vehicle.
Remove the fuel composition sensor fuel composition sensor (FCS) attachment nuts (1).


Disconnect the FCS inlet and outlet pipes from the FCS.


Disconnect the FCS electrical connector (1).
Remove the FCS and bracket assembly from the frame rail.


Remove the FCS bolts and remove from the bracket.

Installation Procedure


Install the FCS to the bracket and install bolts.
Tighten bolts to 10 N·m (89 lb in).

Install FCS and bracket assembly to frame.


Install FCS bracket to frame nuts.
Tighten nuts (1) to 17 N·m (13 lb ft).


Connect the FCS inlet and outlet pipes to the FCS.


Connect the FCS electrical connector (1).
Lower the vehicle.
Start the engine and check for fuel leaks.

Hope this helps.

Sep 02, 2011 | 2002 GMC Yukon XL

1 Answer

P0178 code what the most likely thing wrong

Sorry, I dont know much about this but i can tell you what the code means:
P0178 Fuel Composition Sensor Circuit Low Input

Apr 11, 2010 | 2002 Chevrolet S-10

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