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I have a 2007 C6 Base and I recently changed the spark plugs. Before I changed them, it ran okay but stutters here and there. I changed them out and start the car and hear a loud fan kick on and an error message Engine hot AC off. It was a cold start too so I'm kinda clueless.
Wasn't sure if I didn't seat the plugs correctly or maybe I hit the coolant sensor above spark 1. Never had this error before and I'm sort of stumped on what to do next. any help is appreciated.
Yeah it seemed to be okay. I did unplug the connector and plugged it back in but same error. That's the only thing I can narrow it down to being a temp error.
If you have a DVOM you can easily check this 2 wire thermistor circuit…a 5 volt reference voltage on one wire (yellow) and a low reference ground on the other (tan)…if connector were unplugged you would see -40 degrees I believe on your coolant temperature gauge…if you have a scan tool see if you have any “pending” codes which will illuminate the check engine light after the problem still exists after the next drive cycle…if a ECT code pops up the IAT sensor or its wiring may be skewed and cause this code to set.
I may have to get a scan tool then. I didn't run it long due to the error and didn't want any internal damage. Spark plugs wouldn't be related to it would it? Since it just happened after installing them. Seems like if it was spark related, it wouldn't run at all.
I may have to get a scan tool then. I didn't run it long due to the error and didn't want any internal damage. Spark plugs wouldn't be related to it would it? Since it just happened after installing them. Seems like if it was spark related, it wouldn't run at all.
Don’t think it’s plug related…you can get a good bidirectional scan tool these days for less than $500.00…you can’t diagnose these cars without one…is your coolant temp reading 100 degrees and DIC shows XXX ??
This is a good one and 24% off right now…like I mentioned you can check the sensor with a DVOM and the sensor itself with the ohm meter setting on it…your next ignition cycle may reveal something if there is a problem.
Well just let us know if the check engine light illuminates and what coolant temps you see on the next start up…if it comes back and if you have the equipment or electrical knowledge to test this find an auto electric or diagnostic shop in your area…it’s not a blown fuse as everyone hopes their issue is.
For sure I'll check tonight. Is it okay to run it like that to at least check with fans kicking on so high. I believe it's not getting a Temp. reading so the car trips into overheat mode when its not actually overheating. I only had it running for 30 secs tops.
You can run it but see what the gauge and DIC are showing…if the ECT were disconnected the fan wouldn’t kick on like that at high speed on startup …if the 2 ECT wires were shorted together it would because the engine computer is seeing high coolant temps at 300 degrees…also the injectors would start shutting off and the car will run rough because the ECM is trying not to let the engine get any hotter…that circuit and the IAT which are both thermistors you can jumper together the 2 wires without frying the engine computer…any other sensor with a 5 volt reference if you short that 5 volts to ground will smoke the computer sometimes...if the ECT were bad you just need to remove the #1 plug wire and use a deep socket...no need to remove the alternator.
Cool cool, another thing is the car has been sitting for 6 months so the battery was completely dead. Used a jump pack and it fired up without this issue. Charged battery with a tender over a couple days, change plugs and pop battery in and the problem pops up. Could the battery just be too shot and causing computer errors? Did have a little trouble getting to spark 1. Maybe I bumped the sensor too hard. Hard to say. Just trying to narrow down things and figure out the cause.
Yes, if a battery goes dead that’s not good…get a new one !!…low battery voltage can cause a lot of electrical issues especially the cars modules…mentioning someone like this in your first post is critical…get a battery with the highest Reserve Capacity or RC is helpful…every time a battery drains like that shortens its life considerably !!…with an AGM battery that goes completely dead sometimes it may not even take a charge at all.
Purchased OEM AC Delco gold 90. Will update when I get it in a few days. it has to be the battery messing with that sensor. I hope so anyway. Thanks for all the help so far.
Installed the new battery and same thing, although I inspected the coolant sensor plug and the pins pulled out easily so I'm assuming it can't plug into the sensor. Ill just buy a new plug and sensor of need be.
Help super confused.
