Warm engine restart

Ross

I am having a warm engine restart problem. I see it is common on the 350 mag mpi. What is the fix?

Black_Diamond

I’ve not heard of that being a problem. Mine fire up fine, cold or warm. 

skennelly

Vapor lock?  I've heard of that happening on warm engines..not just 350's.  Never experienced it on mine.

Black_Diamond

Vapor lock would be rare on a FI engine. Plus these all have some variant of the cool fuel module.  I’d be looking at cap/rotor/plug wires as a start. 

aero3113

It could be the coil. 

PickleRick

I second  @aero3113, coil and or ignition module if equipped would be prone to showing failure after a little heat soak and are common failure parts in street applications.  Ive seen ignition modules mounted both under the distributor cap and bracket above the valve cover on vehicles.  The automotive shop next door keeps good used spares of these 2 parts at all times to test a 4.3/sbc powered vehicle that is exhibiting a no spark symptom.  You can test spark with a timing light.

Is the engine spinning over normally when warm or does it start drag/spin more slowly?

Ross

Thanks all, When the engine is warm I have to restart like it was flooded. I'm changing out the idle air control vale and if that doesn't work, I'll look at the coil . Starts fine when cold, but floods when hot.

PickleRick

Now the plot thickens.  I don't think it will be coil or ignition module being that you are having to give throttle to restart.

First off check the compression of the warm engine and inspect/read all plugs.  This could be the signs of a failing/aging motor. Rule this out before digging in too deep and tossing lots of parts at it.  

Next, a leaking injector (s) or failing tps sensor could also be the culprit. What are the fuel rail readings when warm compared to cold?  

Also does the engine sound fine turning over when warm? Is there any chance of a leaky riser/manifold gasket that's allowing some water to suck back into the cylinder on shut down and start up when warm?  It might only be leaking when she's hot.  Just spit balling ideas at this point but these are the simple ones I'd probably start with to rule out.