Strange unknown noise

JOE1983
1h
I been having a similar nose I cannot figure out. When I park my car after driving it and wait ten minutes. When I restart it. My engine rpms drop and it almost sounds like a growling sound coming from the fuel tank. My fuel pump has been changed. This weird nose has been going on a long time. Does anyone else have a clue?

Not sure what you mean by “similar noise” , but it’s p ossible you are hearing something in the exhaust system rattling. That can occur sometimes only at certain rpms, due to the physics of “sympathetic vibrations”. Your engine may only idle at those rpms during start up on hot starts for some reason, and that’s the reason you hear it only then. Ask you shop to inspect the exhaust system for loose hangers and that the cat heat shield isn’t rattling.

Its possible its just the fuel pump noise. Its just an electric motor so is maybe vibrating against the tank or maybe the tank was installed a little different than before. Outside of a looksee to make sure everything is tight and nothing is against the tank I wouldn’t worry about it. Years ago my Park Ave developed a growl from the fuel pump at 20,000 miles. It wasn’t that noticeable and never caused a problem for the six years I owned it.

Okay so an update with this vehicle showed an inconsistent ohm reading to the throttle. I replaced it so voltage was in spec of the vehicle. Resetting the codes I have made putting it on. I went for a test drive and car shook and stalled out with a 335 code. I went to work and shook really bad with rpms going haywire. Today I drove it and every time I waited 15 minutes just so it would start again. When it did the fuel injectors were clicking hard and it stayed alive luckily long enough to get me home. First I was thinking a crank sensor or ecu but now I’m thinking the ignition coil since I read it could have similar issues. I will not drive it far until I get it figured out. Has anyone had a similar problem.

The code is for the crank position sensor. If that part isn’t working correctly, you’d get very rough engine running. Take a look at the sensor and its connector, maybe you’ll see something wrong, like a broken wire or corroded connector. Has there been any work done in the area of the sensor, for example something which might have affected the reluctor ring (the thing the sensor senses).

No well they replaced the timing belt a few years ago and had a new sensor put on. I looked at the wiring and couldn’t tell. Some of it runs behind the timing belt cover and behind the timing belt. It’s a hall effect type and ohms like 500 from red to the signal wire. I’m getting 12 volts There like there should be at the harness

Did any of these symptoms start immediately after the timing belt job?

Not that I was aware of. He replaced the belt because it was time for one. Id hate if it was the sensor because i know that’s behind the crankshaft hub and be expensive to repair. The engine did start surging meaning the rpms went really high by itself after switch gear. But hard to say if it was related. Every time I re connect the battery it seems like the rpms want to go really high but does drop. Without making the car speed up.

Update…I changed my ignition coil and car gets me from point A to point B. I smashed that coil open and white powdery blue looking and smells burnt up. Though the sensor on the crank shaft could be weak so I might change that sometime soon.

Keep us informed of your progress. I expect there may still be a lurking problem.

Well I did change the crank sensor and that was not a particular easy task considering how tight they torque the harmonic balancer on. Though I did get it off and putting it back together I over torqued it and broke it the bolt. I had to get it out and get another one from a junk yard. The engine runs great. My only concern is that when it is cold it sounds like a motor boat in reverse and drive until it warms up and then the sound disappears. It’s like that all the time. The trans fluid looked a little low but it was rebuilt. So if it is low I’m wondering if that can cause the noise.