Pulled codes, possible fuel pump failure?

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Hey guys. I have a 1994 ATX with 52k miles. I drove to San Diego from AZ last week and my CEL popped on for about five minutes just as I was getting into San Diego. It then turned off for the remainder of the trip and the car ran perfect back to AZ averaging 26mpg. I decided to pull the codes once I got home to be on the safe side. I got 176, 177, 212, and 543. Do these all point to the fuel pump going out? Thank you.
 

zoomlater

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From the Shophoenix website for codes:

176
(M) Oxygen sensor not switching - system is or was lean Left or Front HO22SSS - Fuel control

177 (M) Oxygen sensor not switching - system was rich Left or Front HO2S - Fuel control

212 (M) Ignition TACH signal was erratic (module/wiring) or SPOUT circuit fault - Ignition Systems

543 (O) Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits
(M) (Service 556 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits

Have you pulled codes before on this car and then cleared them before this last check engine light? If not, I would clear the codes then and check them again after the light comes on again.

An easy way to check if your fuel pump is good, is to depress the Schrader valve in the middle of the engine snakes. If you have a fuel pressure gauge, you can see what the measurement is when you turn the key to the on position, but not start it. It should be around 35psi. If you don't have a gauge, then just depress the pin and fuel should shoot straight up. Have a rag over it. Can you hear the fuel pump running when you turn the key, any strange noises?

Here is a thread where they had a spout code and the fuel pump code. Maybe someone else has had a combination of these codes. You can search this forum by putting in the code or words like spout and see what threads pops up.

Low rpm sputter 92 MTX | SHO Forum
 
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No difference in performance when light was on. I didn’t think to clear the codes. I will try that, check for fuel pressure and report. Thank you guys!
 

BaySHO Performance

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The only one of these codes that would have caused the CEL to come on is 176.

176/177: The front O2 sensor isn't working. Put new ones in front and rear: Bosch 15716 for the ATX.
212 can be ignored: doesn't affect engine performance
543 Fuel Pump Secondary Circuit Failure: this may indicate a problem, either with the CCRM that contains relays for the pump and fan, or the pump itself. But be aware that this code gets triggered if the car ever stalls (more common with an MTX).

As the car is running OK, can't be an issue. But if the car does die and you get a 542, 543, 556 or 557, then you will need to investigate further: attach a voltmeter to the fuel pump cutoff switch in the trunk and turn the ignition on to prime the rails, but don't start the car. If you don't get voltage at the cutoff switch, bad CCRM. If you do, bad pump.
 

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