Q: Losing coolant, high idle rpm, 2x P0300 1x P1111

asked by on

Hello, I've been having some trials with my '05 Sentra SE-R Spec V lately. My idle rpm has been fluctuating between roughly 700 and 1600 revolutions per minute, and the car is quite loud. More importantly, I'm losing a lot of coolant from my reservoir with no visible leaks. I am suspecting a head gasket or intake manifold gasket. The hard part is figuring out exactly which one and if my rpm problems are related or not. My oil and coolant are not mixing and the misfire occurs on startup, particularly with a hot engine.

I do not have any equipment to pressure test the cooling system and am lost on where to turn. I'd like to figure out exactly what is wrong with it and what options I have available. Do you have any advice or tips?

My car has 194000 miles.
My car has a manual transmission.

Hello. From what you describe it would appear that there may be more than one issue with the vehicle. The rpm fluctuations can be caused many different things. A few things I would check are the idle air control valve, and the any vacuum lines for the possibility of a vacuum leak. Coolant loss with no visible leaks can be difficult to diagnose. It may be possible for you to rent a cooling system pressure test kit from an auto parts store, sometimes even free of charge. A cooling system pressure test would be best way to determine if there is any internal, or external oil leaks.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Losing coolant, high idle rpm, 2x P0300 1x P1111

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car wont turn over clutch ism clicking

I would recommend checking your alternator as well as all fuses. Test the alternator with a multi meter to ensure that it is maintaining 13.8 - 14.2 volts while the vehicle is running. Next, use a circuit tester to test...

Q: Car revs up and won't rev down. Changed ICV

High idle problems are often times related to vacuum leaks or lean fuel conditions. I would start by checking for vacuum leaks and other fuel delivery components, such as the mass air flow sensor, injectors, throttle body, etc. High idle...

Q: Q: Check engine light

Did the cam shaft or cam shaft sensor get replaced. You are having misfires and should get the vehicle scanned to see if one of the codes is to a misfiring cylinder. You may have leaking oil from the valve...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.