Q: Truck idled, ran rough, fluid streaming from motor

asked by on

A very bad knocking noise has developed in my dad’s truck recently. It has that sound as if something is loose. A couple of days ago when I was driving his truck and I got to his house, the truck idled, was running rough, and then the engine almost shut down. There was a stream of fluid pouring from the motor and so I opened the hood and saw that the master brake cylinder lid was loose and the brake fluid was spilling everywhere. Now, the truck has a muted knocking noise when I start it. My dad thinks he changed the oil and put synthetic oil instead of regular 10w-30. So I'm thinking that he did not change the oil and kept the same oil that was in it and just added the synthetic oil. I don't know if this happened or not. He’s a bit forgetful these days. I don't know if that is what would make the knocking noise, or not. Perhaps it is the brake fluid that has gotten inside the cylinder. The oil pressure lights read a bit high and my dad also told me that the truck has stalled coming up their road. Now he has no transportation and I want to fix this for him; he needs my help. We are hoping that it is a simple fix so he won't have to scrap this truck. In your experience, what will fix my dad’s truck?

Hello there, thank you for asking about your car. It’s highly unlikely that brake fluid entered the combustion chamber. The noise also would not be caused by using synthetic oil instead of conventional oil. As for the oil pressure, I’m not sure what your dad considers too high. With the engine fully warmed up, oil pressure should be about 24 psi at 3,000 RPM. To know for certain what’s going on, a professional will need to listen to your vehicle firsthand. A certified technician from YourMechanic can come to your home or office to inspect why your truck is idling roughly and make any necessary repairs.

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. Truck idled, ran rough, fluid streaming from motor

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: My car's Check Engine Light came on. The code is for engine knock sensor 1. Does this mean it is bad?

If your Check Engine Light came on for the knock sensor circuit then it is likely that there is an issue with the sensor. Knock sensors are designed to help protect the engine against detonation, commonly referred to as ping...

Q: Loud sound when eccelaratjng.

Hello Hazel, thank you for writing in. When the noise is associated with acceleration, then the issue is likely exhaust, transmission, or engine related. There is also the option that the RPMs are reaching higher levels before the vehicle shifts....

Q: Clutch has to manually be lifted from floor

Hello! This reminds me of a similar experience I had last summer. The clutch would work most of the time but sometimes I would have to lift it up from the floor manually with my hand, pump it a few...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
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.