High RPM

[rw87tt]

What causes high RPM at start up? After which it quickly comes down and idles normally. Problem is it makes the lifters rattle and makes other noises untill it builds oil pressure.

 

[Alex7747]

the fiav in the trottle body causes that in cold start. its normal.

 

[josh408]

He's right. But once the car is warmed up the idle should be normal and the noises should stop

 

[steve]

How high is high? Cold the engine will start up and the Fast Idle valve should cause it to run about 1500 RPM.

 

[rw87tt]

Thanks for the replys. Steve, If I were to guess. It's probably no more than 2000 RPM. It quickly comes down. It just makes engine stuff rattle. It doesn't rattle all the time. Probably half the time and the severity varies. I'll pay closer attention to the rpm when I start it up. Thanks a bunch for any feed back.

 

[cbarr0288]

Thanks for the replys. Steve, If I were to guess. It's probably no more than 2000 RPM. It quickly comes down. It just makes engine stuff rattle. It doesn't rattle all the time. Probably half the time and the severity varies. I'll pay closer attention to the rpm when I start it up. Thanks a bunch for any feed back.

In cold(er) weather on starts my RPMs would shoot up to 2500, pause, then drop significantly to around 500 at the lowest and cause the engine to rattle like it was about to stall. The ECU would compensate and it would normalize, then drive normally.

Check all the vacuum hoses and made sure everything was connected tight. There could be a small vacuum leak. I secured my hose connections, seafoamed, and changed oil. The combination of the three seems to have fixed this. Which helped the most I'm not sure.