Noise is loudest when engine is cold and on the down idle. Noise seems to lesson a lot when engine warms up. Chased the noise for over a month, Parts changed include; Timing belt, Timing belt tensioner, water pump, Drive belt, Drive belt tensioner, Power steering pump, Harmonic ballancer. Ran engine without the drive belt and the noise was still there so it can’t be the alternator or the ac compressor. The engine has only 50,000 miles. I changed the oil. went from 5w 30 to 5w 20 in accordance with the new ford spec for that year and model, noise still there. I tried using Seafoam, Stp and Lucaus oil additives with hardly any results. Someone Please help! It’s driving me crazy! Any thoughts? Low end bearings? Something loose? Thought about removing the oil pan and having a look
Engine has good power, did a full tune up
Year and mileage? What do you mean by “down idle”?
It seems like you’ve done all the right stuff so far. You’ve pretty much eliminated all the belt paths and drive belt accessories. If the water pump is driven by the timing belt, you couldn’t run the engine without that, so it could be the water pump I suppose. I had a rattling water pump on my truck one time. It diagnosed itself when it starting leaking coolant like a sieve. Try a mechanics stethoscope to narrow down where exactly the noise is coming from. Rattling noises can occur from the valve clearance being too wide for example, or lifter problems. Low end bearing problems in a normally driven vehicle are rare unless the engine has over 200,000 miles or it has overheated or run low on oil.
1999, 50 thousand and change, I changed the water pump, it’s run by the timing belt, have one of those stethoscopes on the way, what I meant by down idle, is when you rev the engine, the noise becomes loadest when the engine is returning to idle speed after i rev the engine, kind of sounds like a rattle like noise that does change with increased rpms
Changing the water pump was a total pain, went through 3 gaskets to get it right where it didn’t leak, got the pump on-line for really cheap, the car doesn’t run hot, noise does seem to come from that area, can a new WP rattle? I took off the timing belt and spun the gear, didn’t seem loose at all, and turned smooth, I just don’t know, this is driving me crazy, I have lost sleep over it, lol
Do you have a heat shield on the exhaust manifold or catalytic converter? Either might be loose.
Thanks for the reply, I have all 3 I think, I did take off the heat shield 2 weeks ago, I’ll have to check it out tomorrow, would that make a noise that decreases when the engine warms? Also would it make the engine vibrate during idle?
Yes, either b/c it’s faulty, or if there is some calcium deposits in the cooling system that have lodged in the pump housing. The latter sounds sort of like like marbles being swirled around in a ceramic bowl.
98 escort …cylinder rattle only when driving not in idle mode…Pulled plug rusty looking…loss of power.not overheating.only rattelsas im trying to go faster.thanks Ralph…
Time to take apart the engine, pull the head, and have the valve seats replaced before they break apart and destroy the pistons and cylinder walls. This is a known defect, and most likely the reason why few of these cars still exist.