Engine issues...Please read...

[johnboneske]

I have a 95' SHO, 3.0 MTX, When comming to a stop light if the clutch is in or in Neutral the engine stays at about 1200RPM, when you finally stop it runs about that RPM for about 4 or 5 seconds, then drops suddenly to about 500 to 600 RPM and usually quits. It starts back up just fine, and runs smooth at idle no matter how long it idles for. It just happens when you are at "cruising speed/RPM" when it runs like that... Does that make sense? I dont have any check engine codes... Crank position sensor was already replaced about 20K ago, and the last owner said it ran fine...

 

[frosho]

Sounds like an IAC issue. See if an idle reset will fix it. The procedure can be found here.

If that doesn't work, clean out the IAC with brake or carb cleaner, and try the idle reset again.

 

[rubydist]

it sounds like a sticky iac to me.

the engine should be around 1200 rpm as you coast to a stop at the light. after you come to a stop, it should drop to the ~700 idle speed. it sounds like the iac sticks, and then moves too far causing the stall.

I would clean or replace the iac. fwiw, I have not had much success cleaning iac, they generally get sticky again within a month.

 

[AREA 91]

I have a 95' SHO, 3.0 MTX, When comming to a stop light if the clutch is in or in Neutral the engine stays at about 1200RPM, when you finally stop it runs about that RPM for about 4 or 5 seconds, then drops suddenly to about 500 to 600 RPM and usually quits. It starts back up just fine, and runs smooth at idle no matter how long it idles for. It just happens when you are at "cruising speed/RPM" when it runs like that... Does that make sense? I dont have any check engine codes... Crank position sensor was already replaced about 20K ago, and the last owner said it ran fine...

It's either the IAB, or VSS.

 

[93rev2sev]

^^^

This

Unless there's a vacuum leak. Does the idle speed rock up and down?

 

[itwonder]

Try the easy fix first - idle reset procedure. A forum search will find instructions.

 

[frosho]

Or click on the link I already provided...

See if an idle reset will fix it. The procedure can be found here.

There seems to be an echo in here.

 

[johnboneske]

it runs a steady RPM without "jumping" only drops after the amount of time... I tried the fix...didnt work, now what? How do I fix it? I have the Haynes Manual...

 

[itwonder]

If you have done the idle reset, next step is second part of post #2.