Questions and Answers

Dodge B250 Intermittent No Start Q. I have a 1992 Dodge B250 full size van. It has a 5.2 liter MPFI 318 and automatic transmission. About 150,000 miles, standard brakes, P/S, A/C and cruise control. My problem is one of those wonderful intermittent problems that maybe someone else has had I thought you might be able to help with.

Every now and then my van will not start. The engine cranks but doesn't start. When it cranks it sounds normal, timing doesn't seem to be advanced or retarded. If you wait a few minutes and crank again it will start. For example this morning I would crank and wait until my battery finally died about 20 minutes later.

I came home this afternoon put a battery charger on it for about fifteen minutes turned the key and it fired right up. I just bought this van about six months ago with a cracked cylinder head and have replaced the head had a valve job done/heads surfaced.

I have also replaced wires, plugs, cap and rotor, O2 sensor, and throttle body sensor. I think the problem could be the fuel pump but I don't want to replace a $160.00 dollar part without knowing. The problem doesn't happen for long enough for me to properly diagnose it.

Do you have any ideas what this could be? Or where to look next. I can't seem to figure this one out.

Thank you,
Jamie

A. There are a hundred reasons for this to happen. The most important thing to do is to isolate it to fuel or ignition. And, as you know, that is difficult to do when it is an Intermittent problem like this. The first thing you should do is to see if there are any codes in the computer and go from there.

You can check for spark when it won't start with a spark tester. You can make one from an old spark plug easily enough. Gap it to 0.200" then take a piece of wire and strip off about 8" of insulation and wrap it around the threaded portion of the spark plug. Put a large alligator clip on the other end of the wire and clip it to the negative post of the battery.

The next time it won't start, unplug a plug wire and plug in the spark tester. Crank it over and if it won't start and you have spark, then the problem is in the fuel system. If there is no spark, then you'll know it's in the ignition system.

You might have to do this a number of times before you get it nailed. The other alternative is to wait until it won't start at all.