Cadillac Repair: PCM P0442/Fuel Gauge, fuel gauge, cadillac sts


Question
Hello there, I own a 1999 Cadillac STS. I've received this code (PCM 0442) one week after just having the fuel pump replaced. I've checked my gas cap and all is fine.

Do you think that the shop that replaced the fuel pump could have done something to cause this?

Next, following my fuel pump (with sending unit) replacement, the fuel gauge on my dash is wrong. After driving 120 miles from a full tank, it STILL shows full. So here's what I did next.

From a FULL tank, I've driven it down to 17.8 Gal used on the LED panel. Gauge showing almost empty. Right on the last line. Went to Shell to put SIX gallons in to see what the gauge would do. Gauge went CLEAR over to FULL just from my adding 6 gallons from darn near EMPTY. So... It FLEW back over from just $15 of fuel added (93 Octane).

Your thoughts on both issues? Thanks for your help.

Answer
This sounds like a fault in the new sending unit that was just installed in the fuel tank, Which will need to be tested and most likely replaced.

Please e-mail: onlineautohelp@msn.com

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