Back story/what we have done so far. It is a 2003 Buick Lesabre with 102k miles.
Car started “overheating” on us
Car started “overheating” on us, no engine light. Temp gauge would go from reading halfway to all the way in the red within 1 second. Sometimes it would bounce back down right away, sometimes you’d have to turn off car and restart for gauge to normalize. Verified with infrared thermometer that car was not actually overheating, temp was always 190-200. After doing this for 3 or 4 times, engine light came on and car threw itself into limp mode would not go past 3rd gear. Parked the car until coolant temp sensor and thermostat were both changed. Since then been driving the car around for about a month with no temp issues. Temp stays constant at 194. However engine light will not go away, still showing code for coolant temp sensor. Will try to clear code manually and see if if comes back on.
However a new issue has arisen and I am not sure if it’s related. 3 times now when trying to start car after quick errand, car won’t start unless I give her a lil gas. This is not a problem in the morning and not all the time. Only after for example running into the store for about 5 min and coming back out to restart car. If I am gone for longer periods of time like in the store for 30-45 there is no problem starting. Only after turning it off then trying to restart within a few min. After I get it started it runs fine. Temp still ok, no idle issues. Threw some injector cleaner in and will be replacing fuel filter soon. Any thoughts? Are these two issues related?
I do not think the two issues are related. The second issue sounds like a idle air control valve sticking. This issue doesn’t throw a code. But from how you explained being able to press the accelerator pedal a little allows it to start tells me the story. Cleaning and or replacing the IAC Valve should take care of that issue.
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Buick Code P0128 – Engine Coolant Temperature Below Thermostat Regulating Temperature
Possible causes for code P0128
- Leaking or stuck open thermostat
- Low engine coolant level
- Insufficient warm up time
- Faulty engine coolant temperature sensor
- Engine coolant temperature sensor harness is open or shorted
- Engine coolant temperature sensor circuit poor electrical connection