Question
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Followup To
Question -
Engine coolant had boiled and spilled out of the reservoir after a dense traffic ride. No warning lights no error codes at all. After engine stopped there was no possibility to start it again, except when the coolant sensor became disconnected, but with a quite rich air/fuel ratio. After that E15 was diagnosed, this is normal when the coolant sensor is disconnected. On the ride back with the disconnected sensor the engine operated within the normal temperature range. However, the coolant sensor counts -26 Degrees F while its about 80 dg/F air temperature (manifold air temp sensor counts 76.6 degrees). When I reconnect the sensor no error code but E52 is showing up, however the engine won’t start anymore. There where some self cleared E48 codes and a “Service Soon” light showing up sometimes but both where gone after the engine was restarted. I’ve already ordered a new coolant- and even a new oxygen sensor from the US because an original GM sensor costs 10 times more here in Switzerland than in the US.
My question: Are there any other (electronically) possibilities which could lead in overheating when the thermostat opens (upper radiator hose became warm) and there are no bubbles coming our in the radiator (blown head gasket) and the fans are working? Thought there is no error code at all when the suspected faulty coolant sensor is reconnected.
Many thanks in advance for your reply
Answer -
Wait for the coolant sensor as the computer has shut down the fuel and ignition until the sensor is replaced.
Question -
The sensor had arrived and I replaced them as advised. The engine’ s running fine again, but when I connect a test device after a 15 mile ride then the coolant temperature counted was again up to 217 deg/F while the MAT sensor counted 117 deg/F. The environment temperature was about 75 deg/F. The coolant in the expansion reservoir starts to boil again. Coolant level is ok, upper radiator hose became hot as well, no error codes, no “service soon or service now light” engine sounds good, idle is like those from a new engine (no wrong air). I also disconnected the heater hose from the exhaust manifold to prevent hot air is coming into the manifold. I’m definitely at the end of my knowledge.
Could this happen because of a clogged EGR valve? There was a self cleared E48 Error several weeks ago.
Many thanks for your advices.
AnswerE15 is a coolant sensor failure.
normal engine temp is 220-240 degrees.
Your coolant temp and mat temp is OK.
E52 means that the battery voltage was disconnected at some time from the computer.
Your most likely going to be OK once you replace the coolant sensor, Oxygen sensor and also when you install the new parts, replace the spark plugs.
