essstwokay

Driving about 5 min away today I noticed a ticking noise coming from the front end of my car. Got home and popped the hood to see where it was coming from. Put a screwdriver up to the block and played with the throttle... And it's making a knocking noise. Noticeable without the screwdriver and with. It speeds up with more rpms. Car still drives fine. (but I'm not going to drive it)

Anyone have any ideas? Retainers? Rod knock? Something else?

K1ngfunK

When was the last time you got a valve adjustment?

essstwokay

A year ago. (15,000 miles maybe?)

Also, the noise is coming from the back of the motor. It is not constant. It kind of goes in and out. When I hold it at 2000rpm it gets louder. And the noise speeds up and gets louder with more throttle. Then at like 4000 rpm it goes away

Pinky

Does it get louder when you are driving and accelerate and then virtually go away when you decel? If so you might want to listen to some YouTube videos of spun bearings with S2000's to see if it is the same noise you have. I did and well sadly it was the same!

Early model year AP1's have a habbit of having oil starvation on the #4 cylinder. Mine sounded like it was coming from #3 but a bore scope told me it was #4(against the fire wall). If it was up front I would say it's TCT but it's not.

essstwokay

f@#k.

Yeah I was just looking at videos of rod knocks vs TCT sounds and it sounds similar to both. But it sounds like cylinder 3... But also cylinder 4.

I may be building my motor sooner than previously planned.

Pinky

Do you have a friend with a Bore Scope? Something to look down inside the cylinder to look at the walls.......they will really tell the story!

TCT vs. spun bearing are very different(to the trained ear) TCT is a light rattle sound it's always there and definitely comes from the FRONT of the engine. The Spun Bearing I thought was more of a metal screwdriver tapping inside the engine and had a very unique sound when coming back from an almost stall when revving it. I put my ear on the intake and listened and it was definitely in the #3-4 area and not so much in the 1-2 area and definitely not from the front of the engine. You can also take the rubber hose off the top of the valve cover and listen in there.(should be purring and not get louder from inside there)

I ended up opting for a low miles engine swap vs. re-build or new short block.(though that was b/c of a unique opportunity that presented itself)

Good luck!

essstwokay

Whelp. It's def a knock. Not sure if crank Bearing or rod bearing. I'll be pulling the motor within the next week or two and building it. I'm going to keep the block (which I'm assuming is still fine.. Knock is very quiet and not bad... Have not driven it since i first heard it). So I'll be going all out. I'm going to keep the f20 and do 10.5/1 compresson pistons. Have not decided on S/C or turbo yet. I was originally Going to do s/c... But I may go turbo now if I'm going to do a full build. I'll try and keep ya updated!!