So I’ve changed out the purge solenoid three times. I also changed out the charcoal canister and the vapor canister vent as well.
2013 Yukon XL Denali idle and startup issues. SOLVED
- Thread starter krekelly
- Start date
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Today, the A/C wouldn't turn on stating that the engine was too hot and needed to cool down before the AC would turn on. I'm at my witts end!! The engine thermometer on the dash was reading a normal temp and didn't waver. The AC ended up kicking on after about 30 minutes of driving. Not sure what to make of that.
Check the coolant temperature with an OBDII scan tool. I recently had a vehicle with a bad coolant temperature sensor that was reading about 60-80F too low. You would not see it on the dash temp gauge when starting because the gauge just showed full cold, it would dump too much fuel when trying to start the engine. Was not very obvious that the temp was colder than expected when warmed up. WOT while cranking helps with "Clear Flood Mode" but once it started it still ran too Rich and loaded up a bit.
Female terminals in the connector may also be spread and loose and/or some corrosion inside the connections. Bad connection could also possibly lead to a too high coolant temp reading.
After vehicle has been sitting before starting, connect an OBDII tool, read the Coolant Temp, it should be very close to the IAT temp and what ever Ambient temp is as well.
I doubt it is an injector leaking down, this does not happen very often. Assume this is a push button start engine, you may also try to start engine without foot on brake, to hopefully prime fuel rail, then turn of and put foot on brake and try to start again.
Female terminals in the connector may also be spread and loose and/or some corrosion inside the connections. Bad connection could also possibly lead to a too high coolant temp reading.
After vehicle has been sitting before starting, connect an OBDII tool, read the Coolant Temp, it should be very close to the IAT temp and what ever Ambient temp is as well.
I doubt it is an injector leaking down, this does not happen very often. Assume this is a push button start engine, you may also try to start engine without foot on brake, to hopefully prime fuel rail, then turn of and put foot on brake and try to start again.
this is a clue, you need to use that scanner and see what the temperature readings are, ambient versus actual versus what the computer is being told, also see what the map sensor is showing, I do not have specs memorized but the reading it shows is based upon your elevation.
I believe the temp sensor on the passenger side of the block send out 2 different readings, one to the cluster and one to the ecm or something of that nature.
if the dash temp shows correct and the ac thinks it is hot, then something is not right, this could also explain fuel being added or removed by the ecm because it is all calculated by the assumed temperature.
you could use a laser thermometer to verify actual.
Quick update: while my wife was driving and had the AC issues, she was saying that the engine temp gauge was reading 200 or all the way to the left. The fan kicked on immediately when she started the car, which normally doesn't happen. Lastly, when the AC did kick on, the engine temp gauge read 250, like it normally does. I'll check coolant temps as well as engine temps.
Some vehicles use just a single coolant temperature sensor that provides info the gauge, some vehicles have a coolant sensor for the ECM and a separate sensor for the coolant gauge in the cluster. For a 2013 model I would expect only a single coolant sensor for the engine that would feed data to the ECM and gauge cluster buss?
If the coolant temperature is reading all the way to the left, assume full cold, when driving or the engine is warmed up, then this is a problem either with the coolant temperature sensor and/or the connections at the sensor unless the engine coolant is so low the sensor is not in the coolant stream, but the engine would likely be running hot enough that the coolant sensor should read hot at some point.
These engines should run right between 194-210F give or take, kind of depends if the engine cooling fans are working properly. If the AC is on usually the cooling fans are commanded on and the engine should not go above above about 205F from my experience. If you are seeing 250F this is too high, but if this is from a basic dash gauge, it may be a mis reading as well. This is where and OBDII tool would be very helpful to see the exact coolant temperature.
You could also have a bad ground somewhere that is causing erratic coolant temperature readings or a erratic dash cluster temperature reading. Maybe a bad engine to body ground??
This looks like the part for your vehicle, but you should double check. It is the sensor with a replacement connector end which may be required or would be good to have if needed.
If the coolant temperature is reading all the way to the left, assume full cold, when driving or the engine is warmed up, then this is a problem either with the coolant temperature sensor and/or the connections at the sensor unless the engine coolant is so low the sensor is not in the coolant stream, but the engine would likely be running hot enough that the coolant sensor should read hot at some point.
These engines should run right between 194-210F give or take, kind of depends if the engine cooling fans are working properly. If the AC is on usually the cooling fans are commanded on and the engine should not go above above about 205F from my experience. If you are seeing 250F this is too high, but if this is from a basic dash gauge, it may be a mis reading as well. This is where and OBDII tool would be very helpful to see the exact coolant temperature.
You could also have a bad ground somewhere that is causing erratic coolant temperature readings or a erratic dash cluster temperature reading. Maybe a bad engine to body ground??
This looks like the part for your vehicle, but you should double check. It is the sensor with a replacement connector end which may be required or would be good to have if needed.
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250? that's not right, the needle should pretty much be right in the center give or take a smidge which calculates to 190-205 or so , mine generally hangs around 194 (via obd port)
unless of course it is a cold start in which case the needle rises from the left and moves slowly to the center as it warms up
My bad on that number. I wasn’t near the vehicle and did a google search. Trustworthy right?!? It’s normally 200 or so.
I just ran the OBD2 test and the ECT temp is 136°.
I apologize! I wasn’t near the vehicle and just did a Google search. I know that my vehicle runs at almost 12 o’clock on the dial. For some reason, I was thinking the dial was 250°. The center of the dial, however is 210° and it runs a little south of that closer to 200.
I currently have the scanner working. ECT temp comes back at 136°.
You’re right it is not right! I had 250 in my head and apparently I was wrong. I just looked at it and straight up and down is 210°. It runs a little cooler than that around 200. I just got done with the ECT test and it is coming back at 135° roughly.
I’m gonna grab an ECT sensor and replace it tonight.
Alright good news!! ECT sensor was replaced. However what should have been a 10 minute job turned into a whole ordeal. The original sensor was cracked at the threads and when I went to remove it, broke off. The probe and half the threads were stuck in the engine block. Had to use an easy out to back it out. Also the electrical connector broke off inside the original sensor.
Thankfully it all came together. She runs quieter and the AC runs colder. We’ll see how things work out the next few weeks.
Thankfully it all came together. She runs quieter and the AC runs colder. We’ll see how things work out the next few weeks.
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This was most likely the problem with the starting and AC/Fan operation.
I assume you will know within a few days if the problems have been correctly by replaced the Coolant Temperature sensor.
Hope this solves your problems. Easy fix except for the fact the sensor broke off in the engine.
I assume you will know within a few days if the problems have been correctly by replaced the Coolant Temperature sensor.
Hope this solves your problems. Easy fix except for the fact the sensor broke off in the engine.
I hate breaking threaded components off in anything on the vehicle. If I have enough time, I spray penetrant and let sir overnight. Or first part of the job and let sit while I do other work. No salt on roads here sure helps.
I’m fairly certain that this broke off before me even touching it! In fact, I think that’s the whole cause of my issues, I think the part was over tightened when the mechanic installed the new motor back in March.
Sorry, I did not read far enough back to see anything about a new motor in March. Sounds like it was overtightened.
No need to apologize. I’m just putting the pieces together. It’s been a “fun” journey
Joseph Garcia
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As Hannibal Smith used to say, "I love it when a plan comes together".
This is just another example of Forum members helping fellow Forum members troubleshoot an issue and arrive together at the root cause. This Forum ROCKS!
OBSandaNNBS
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It's not always fun but fixing it yourself is always satisfying! Every time you fire it up and it runs good
Ain’t that the truth! This time around was a lot less of the fun and a lot more of the thankful when it fired up. I’m happy to have saved quite a bit of money.It's not always fun but fixing it yourself is always satisfying! Every time you fire it up and it runs good
