Hi,
My name is Josh. I have a 2011 Nissan Frontier SV 4.0L 6 cylinder with automatic Transmission with approx. 155,000 miles current OBDII codes include Bank 1 Sensor 1 O2 and Mass Air Flow Sensor. I have been the sole owner of the truck since i bought it in 2011. This truck has been owned and driven in New England Area the last 10 years.
While driving my truck a very short distance this morning less than a mile my truck started making a super loud noise. The only way i can describe the noise is a grinding metal on metal noise that sounds like it is coming from the engine, sounds like a jet engine ready for take off. When i first started hearing the noise, I didn't notice any change in performance for the remaining short distance I drove it to the nearest parking lot and parked in the nearest spot I could find this was probably less than 500ft of additional driving after the noise started. After parking the truck was immediately turned off. The distance driven total wasn't even enough distance to allow the truck water temperature to heat up to normal operational temp, it was still cold when it was parked. After allowing the truck to sit for a few minutes I attempted to restart the engine, it appeared to have no issues starting, however, the original sound had gone away and there was a new sound as if the engine was running rough sort of like a knocking or ticking and chirping sound and within approx 12 seconds the loud noise originally heard came back very suddenly. I repeated this process and got the same results and also took a short video and uploaded to my google drive, here is the link:
https://drive.google.com/file/d/1gLH12XBT3bydPlH8V5YiyM700xkKNbEP/view?usp=sharing
After taking this video I popped the hood and did a visual inspection of under the hood I checked the oil and it was full and looked fine, also I check the coolant level, which still had the radiator full and a decent amount still in the reservoir. In addition I also checked all of the hoses to make sure they were all snug to make sure any of the vacuum hoses didn't come off or loose causing the vehicle to run rough. I also started the truck one last time while looking at the dash to make sure the oil pressure gage showed oil pressure between L and H like it normally does and also a quick check for unexpected dash lights. There weren't any unexpected dash lights and the oil pressure was normal.
I am trying to get an idea of what this might be before I have it towed to a mechanic shop, so that I'm not being told something its not so they can get more money out of me.
My gut feeling diagnosis is the water pump, but i have never had a water pump go bad on me with any of my vehicles, so i have no idea what it sounds like, however, after this morning and looking back at a series of events it makes sense to me that it might be the water pump. The following I have taken into consideration to come up with my suspect diagnosis.
About a year ago my heat stopped working in the truck when the truck was at idle and the only way to get heat was above 2,000 rpm. I originally though it was the thermostat went bad so I was getting ready to do the thermostat replacement and then realized my coolant was low, so i refilled the coolant instead and my heat came back during idle but that only lasted about a week so then I checked the coolant again and it was a little low so i topped it off assuming i didn't get all the air out of the coolant hoses when i initially refilled the coolant. Since then about once a month I have been adding coolant about a gallon of coolant approx. every 3 weeks or so. After 2 months I started to suspect the water pump was leaking and then learned of the weep hole and figured the vehicle was getting old maybe it was normal for the coolant to leak more from the weep hole and dismissed the issue and just kept adding coolant as needed. Just last week I changed the oil in the truck, however, on the under side of the oil cap i saw some brown sludge and assumed that I had a blown head gasket, but after looking at the old oil, it was a normal dark brown color and had the normal oil consistency to it, I added some stop leak to the new engine oil just in case and didn't notice any white smoke from the exhaust. I also took the ignition coils off and took the spark plugs out and looked inside with a flash light for any signs of fluids that weren't supposed to be in the cylinders and surprisingly they were actually pretty clean. So I figured because of all the super short trip driving I had been doing I was just getting a little bit of blow back into the crankshaft that might have caused the brown sludge, but just to be on the safe side in emptied all the coolant and refilled with new coolant and added a small bottle of K-seal. After starting the truck i though I heard something that sounded like an occasional knocking sound that would come and go, and I figured that maybe I still had air in the coolant hoses so i turned the truck off and and burped the hoses and added more coolant and repeated this process about 3 more times until I couldn't add any more coolant, by this time the knocking sound seemed to have disappeared, so i thought i was right about the knocking sound being air in the coolant system. I also chose this time to add some fuel injector cleaner to the gas and drove the truck around the block and noticed an almost immediate positive change in performance and engine idle. The more i drove the truck this last week the better the engine seemed to operate all the way up until today when it all of a sudden started making that god awful loud grinding noise. This noise came on so suddenly it doesn't make any sense to me after the truck running like a dream this whole last week.
I apologize for the war and peace novel and I'm sure there is plenty of irrelevant information here. My suspect and my hope is a bad water pump. Please anyone let me know if you think I am way off on this or if I'm headed down the right path.
My fear is a blown head gasket, but also makes the least amount of sense to me, because its missing all the other signs of a blown head gasket. I don't want to keep starting the vehicle or drive it anywhere, so that if it is something more serious than a water pump I don't end up damaging it anymore. I really don't know anything about vehicles in the slightest. I only recently started doing my own vehicle maintenance out of necessity to save money because finances have been tight this whole past year.
Thank you for you help!
It sounds like the radiator fan.
You need a helper for investigating.
There's a lot of different things going on here, and it's very hard to separate cause (or causes) from symptoms because of the complexity.
So, what we do know, from your narrative, is that you're losing coolant. Sometimes coolant loss can come from a leak close to or around the intake manifold, which, when the engine is running, is so hot that it evaporates the coolant. (So, you never see it) You might have a coolant line or lines that are brittle and leaking. So, you should check for that.
In fact, it would be wise to very carefully check all the hoses going in-and-out of the engine. as well as any gaskets (including the thermostat gasket) that funnel coolant inputs and outputs to and from the engine.
If there's a coolant leak from hoses or fittings for hoses, that would obviously affect the water pump. Parenthetically, if there's compromised hoses, I doubt that K-Seal would be useful.
You can run a very simple block tester on the radiator to determine if there's combustion gases in the engine. Scotty has videos showing how this can be done. (See the bottom of the post).
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Clean the Mass Air Flow Sensor. It's easy and cheap to do. Scotty has a video on that, as well. (See the bottom of the post). Also, as easy and cheap, you should also clean the throttle body.
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Now, if the 02 sensor is bad, it will make an engine run rough (and play havoc with the 14.7/1 ratio of air to fuel). There are ways to test an O2 sensor. Google it. You'll find tutorials. And, if you have a decent OBD II scanner that can check for problems with the cat, do that, as well. (Usually, you'll get a P0420 code).
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Obviously, the vehicle might benefit from a fuel injector cleaning. (Scotty has a video on that, as well). Erratic spray patterns will give the ECM and engine fits.
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Scotty usually advises to start simple and cheap. Do the obvious things first (like very carefully looking in-and-around the hoses and inputs and output of the engine and the intake manifold) which is what I'm suggesting.
If you do the simple things systematically, you'll eliminate possibilities and then what remains becomes what it must be. (It's very much like detective work). Keep a log of what you're doing, in case this does eventually go to a diagnostically-oriented mechanic.
I spent nine years in Massachusetts, in places like Lowell and New Bedford. I know what a beating a vehicle takes during a New England winter, particularly along the coast.
Good Luck.
https://www.youtube.com/watch?v=v0U8Iyf0kk4
https://www.youtube.com/watch?v=xQGSkWEC_u4
Yeah I’m with Joe on this one, it sounds more like a plasticky grinding noise, rather than a metallic one.
Ofcourse you’ll need a helper to look under the hood while the noise sounds. It’s so loud that it should be easy to pinpoint with the hood open.
Does it do it with the AC on/off?
