I have an 89 Dakota 4 cyl, when the weather gets above 90 the truck will run for awhile then out of the blue it will just stop running and die. if you try and restart, it will start after 2 seconds or 15 min whichever it chooses. to me it sounds like a vapor lock, but my girlfriend thinks electrical. any ideas??

I have put a DEI sleeve on the fuel lines and put a block of wood against the valve cover to help prevent vapor lock but it still quits from time to time.

 

Well first basic troubleshooting....when it won't restart is it missing fuel or spark? Does your 89 have a mechanical fuel pump or electrical? I thought 89's were electrical (at least on the 3.9....maybe the 4cyl carbs were mech?). If it's electrical, almost assuredly it is NOT vapor lock.

 

fuel pump in the fuel cell

 

If it has a fuel cell, you need to go back to the mods made to install a fuel cell and find out what's happening there.

WAY before you start checking anything factory on your truck.

RwP

 

Sorry for the misunderstanding
It has a regular fuel tank.Now for a little update--I took the truck on some arrends and everything worked fine,got home shut the truck off ,did some chores and got back into the truck,---wouldnt start ---tried to start it for 3+ minutes and finally got it started.When grinding on the starter---no fire. then it started like nothing had happened,ran fine.

 

Again you're going to have to do some basic troubleshooting....air fuel and spark are all your engine needs to run. Assume you have air so are you missing fuel or spark? Next time it happens pull a spark plug wire and hold the metal electrode near your cast iron manifold....have someone turn the engine over....do you have a spark? If yes we can probably assume fuel issue....if no then spark issue.

For spark look at anything electrical. Distributor and coil being the main components. Check that all your grounds are tight and clean....there are several on the firewall and interior fender walls.

For fuel check your fuel filter....have you ever changed it? It's on the frame rail driver side ahead of the rear tire. Do you hear your pump kick on when you turn the key to on? Do you hear the ASD relay click when you turn key on? It's on the drivers side fender in the engine bay...there will be two or three relays here depending on if you have AC. Have someone listen to it see of its clicking on.

There's a multitude of reasons it is intermittently starting but it's more than likely a component failing when it gets hot. You just have to start narrowing down cause.

 

most of the time it happens in traffic or at an intersection so its impossible to do any troubleshooting---just get the POS out of the way!!