So I have a 1998 4Runner with the 2.7L 3rz that I tried to start this morning.

Engine started for a minute, then immediately died. After it died, it sounded like it was not making compression/timing chain was broken while it was turning over. I have heard the sound before and know it well, it was just turning over freely/without resistance.

It wouldnt even hiccup trying to crank. I got my buddy to crank and I confirmed that the chain/cams were turning, but it was not making the *thud thud thud* from each compression stroke while turning over.

After a 5 min or so, I cranked it for a bit and it fired up. Ran ˟˟˟˟ty for a bit, then cleared up. It runs as good as new now.

I unplugged the coils and turned it over and it made a solid *thud thud thud* that it should while turning over.

How does and engine not make compression, then make compression?!

THIS DEMON ENGINE DEFIES PHYSICS

Any suggestions would be grand, thanks yotatech

 

Really, the whole post could almost be summed up as - "What could make an engine temporarily lose compression in ALL 4 Cylinders??"

I am quite mechanically savvy, but this one is driving me up the wall

 

Are you positive that the engine is making the "no compression" sound? May be the starter spinning but not engaging the flywheel of flexplate, only way to tell is to have someone crank it while watching the crank pulley when it is acting up.

 

I am 100% sure. Not only was the crank spinning, I took off the oil cap and watched the camshaft+timing chain spin as well.

The engine was turning over with no compression sounds