Vannin' Home Forums Chevy Troubleshooting Hard start when warm

I am having trouble starting the van when warm. When it is cold I can give the gas two even pumps and she fires right up. If I have driven it recently it usually takes 2 or 3 attempts to start. I have been trying 1 full pump on the gas, just a half gas pedal hold, 2 full pumps, and none of that seems to really change or help.

Shouldnt have to pump it at all to start it ....

You're just talking about when it's warm correct?

Ive been on many many trips for weeks at a time, north and south and neither of my vans cold blooded 454 RAT motors need to be pumped


Hard start in HOT weather means you have an amperage prob ... cant get enough to crank the hot starter ..... try going to a reduction gear starter.... way less amps required to turn it over

Another thing is check all ground straps and batt cables as things expand in HOT weather, you may be losin contact

It's not necessarily hot weather, more so running to a store, going in, and coming back out to a warm engine. I will try not pumping the pedal for a few days and see if I can get any more clues.

I see in your other post about headlights the ground straps is a possible answer ... you may need to do a rewire with fresh copper ....

After all the van is over 40yr old

Will do. Shouldn't be too bad and man these ac delco parts are cheap compared to my Audi we just sold!

Sounds like a carburetor problem. I have a similar problem on my 76 Dodge, starts good when cold, when hot after setting, hard to start and an odor of gas after starting, Been told it is the float, possibly the choke, or the carb just needs a complete rebuild. Timing can also affect starting when hot.

Need more detail on your current carb set up, engine specs, including ignition to better diagnose. Very likely your motor is heat soaking, which always makes for hard starts after running. But we need more info

It's a 5.7L V8 with Edelbrock carb. I tried not pumping but it was still hard to start. Also once it starts it dies or almost dies unless I rev it for a bit.

I scheduled a date with our mechanic in a few weeks. I will let you know what they say after they go through it.

Gasoline with Ethanol boils and evaporates quickly causing vapor lock on a hot carburetor. If you can find gas in your area without Ethanol, give that a shot.