Sho Wont Stay Running????????

[erik5555]

i need help ......my 93 sho starts and idles perfect like a champ........but give it like 3-5 mins and the thing will shut down without notice.......butt starts back up and then does it again ....and each time it takes less and less time for it to shut off..........ive replace the crank sensor, water pump,and ignition module in this car because of this and iam still getting nothing??????

 

[Pro*banshee]

your IAC is bad presumably. The IAC relay keeps the throttle open and allows enough air to idle the engine, when this solenoid goes bad it can't keep it open and unless you stay on the throttle the car will stall. A temporary fix which sometimes solves the problem is to just remove it and clean out the area (gently) and re-install the IAC. If you have a multimeter, test it if you can. I got about 11 ohms on my one that I restored to working order by cleaning out the throttle body gently with carb cleaner.

 

[USHOMEISHOU]

sounds like a faulty crank position sensor to me

 

[Mr95Gl]

Swap out your IAC for a known good one. I had the same thing happen to me after getting carb cleaner all over it.

 

[USHOMEISHOU]

Sorry, off subject...

Mr Tire Iron

:laugh_ti:

I Love It!!!!

 

[erik5555]

ok ill give the IAC a try

 

[erik5555]

i took a look in my sho manual and it say the IAC controls the secondaries so i conat be that

 

[mtascill]

Actually it's the idle air bypass valve that the other posts are referring to. This is attached to the intake manifold just opposite the throttle body, attached by 2 allen head bolts. It regulates air flow at idle with the throttle closed. One way to diagnose this is to press lightly on the throttle at idle, see if the car stays running.

If the valve is not opening enough or staying open the engine will stall. Opening the throttle slightly yourself serves the same purpose. If the car still stalls with the throttle open then the problem is likely to be elsewhere.

Have you pulled any codes or noticed any temperature issues? The few min running time seems like a temperature issue with a component, especially with the diminishing run time for each attempt.

If you do pull the idle air bypass, watch the lower bolt doesn't fall into the engine valley, right along with the allen key. You might want a magnetic parts grabber handy for this one.

 

[38SHO]

also check your fuel pressure, its another thing that can cause stalling


Better to know what its NOT then to throw parts at it with no idea