I have a e150 4.9l, that dies frequently when raining. I have replaced the plugs,cap and wires. Taped up the wires to the disributor. When I hit the engine with a garden house the thing won't die. (Except for the dist. and atl.)

However when I am driving around it dies all the time. Many times when I am turning or was just idleling for a short period of time.

Do I need to worry about the electrical connectors going to the diff. or the trans. ?

thanks

 

My experience with the 4.9 is that you must use a quality cap and rotor, like Motorcraft.

 

You aren't spraing the engine directly are you? You can wreck some stuff that way. The engine can take some water, but the pressure from spraying it can get inside a faulty connector, and cause problems.

 

both rotor and cap are Motocraft.
Also the hose is set to a light spray, not trying to hard to flood the engine compartment

 

Try checking for a slight leak in the intake system. had the same problem with my 99 Suburban, turned out I had a vaccum leak at the intake manifold gasket. I kept driving it anyways because I did not know at the time what it was. then as time grew on it started running real bad... take a can of carb cleaner and spray it around the intake etc.. and see if the idle increases or sputters as you are spraying around certain areas.

 

Replace the coil also. Some 4.9's in vans had heater hoses that ran right above the coil and distributor. When these leaked antifreeze got on those components. AF will short out when moisture is present. Once the component arcs over it forms a carbon track in the surface that can't be removed.

 

That has to be an annoying, and certainly dangerous, fault! Do you live in a place where you will see more rain this Spring? Here in So. Cal., the rains seem to be finished.
My guess is your problem is electrical...that is, IGNITION related.
It would be helpful to know if your coil is generating a sparking voltage during the fault condition. This would be easy to observe, but you would have to be careful to not introduce a second problem that didn't exist before.
Obviously, you have not been able to synthesise the fault with a garden hose. Intermittent faults like yours require replication of the fault situation. You can't hit 'em if you can't see 'em.
If you can find out whether the coil IS or ISN'T generating a spark, during the fault, then you will know which direction to look as you work this problem down.
If your van just "quits" instead of sputters or misses before dying tells me the problem lies in the distributor or before the distributor...not a crack between two of eight distribution terminals on the distributor.
My sister's car died in a rainstorm, and she was towed to a garage. The mechanic said a relay got wet. This seemed fishy to my sister, but it does indicate a catastrophic electrical fault that lay outside the most commonly suspected area, that is, the coil and distributor.
One of the spookiest ignition faults that I recall resolving had to do with a shorted rotor, in a distributor on an older vehicle. This had nothing to do with water, but shows the propensity for high voltage to seek a ground, though any defect in a plastic body.
You haven't mentioned that you looked inside the distributor cap, just after a fault condition has occurred. If there is any moisture in there, you car will like sputter or stall. If you can get your stalled van started again, by spraying the inside of the distributor with WD-40, then that tells you a great deal. That would indicate your distributor cap can't keep moisture out.
If your car can "crank" but not start, during the fault condition, then that says that at least you've got +12Volts...at the starter motor, if not at the B+ terminal of your coil.
A sophisticated approach toward solving your problem would be to strap surveillance instrumentation to various points on your vehicle, and to record the goings-on while driving around. This is one way to "catch a thief" that only visits your engine intermittently.
Perhaps you can work out a deal with a car wash.
You have said that the van "dies all the time." Your descripition implies that stalls are brief, and repetitive. This is different from "dying and staying dead." When the van starts up after stalling, does it run rough, or smooth. Roughness points finger at moisture inside distributor housing, typically.

 

kgk,

Welcome to the forum.

Have you checked for any trouble codes?

The above suggestions are good and should be ruled out first, but you stated that the engine dies when idling or turning which brings up another potential problem to check for.

The power steering pressure switch located at the bottom of the power steering pump just above the engine oil filter works by closing when you turn the wheel and cause the pump to build pressure. It signals the PCM to increase the idle to compensate for the additional load that the power steering pump is placing on the engine and prevent the engine from stalling. The rain may be affecting that switch and your attempts to duplicate the problem with the garden hose are not getting it wet.

Just something else to check if the ignition basics don't solve the problem.

Gene

 

I know a guy who had the same problem with his 95 F-150, he ended up locating the problem after damn near replacing everything electrical, he had a cracked coil, water would splash in and it would cut out.

 

It finally started to rain heavy again. The van died twice today.
I was able to remove the engine cover from the interior. I do have spark, got shocked several times so it is strong.

The engine is very dry from the disributor on back, both sides, No water on the intake manifold either. Cap and wires are very dry

Any other ideas

 

still voting on wires, been there, done that on an '85 4.9 Expensive wires brand new leaked in the rain. $15 Wells wires from Walmart lasted 3 years.

 

Still unclear here on the "manner of dying" your car exhibits. Does it sputter, backfire, and die? Does it fire at all? Even if there is no firing at all, you might still have traces of water inside the distributor. You can remove this possibility by spraying inside of distributor cap with WD-40; it displaces water. Less likely, but still possible, is that you have compromised insulation on B+ wiring leading to coil; or between coil and distributor; this makes for intermittent faults.

If you have water inside distributor, you'll get spark (hence shock) but the timing won't be right. Therefore, the car won't run. Analytical instrumentation is much more effective in revealing this, than feeling around for a shock.

 

If you're getting shocked, it's aching outside of the wires, it should not.

 

You don't say what year van you have. You have a carb, or fuel injection?

 

Hello,

Great news I think ?

To answer some question's:
The van is a 1992 4.9l Fuel injected with 205k miles. All original and does not leak or burn oil. The codes are fine (flash 11 or 111)

The van just dies without warning when raining, wait 10-15 min. and the van will fire up, and act great. Like nothing ever happen.

Every time it dies I am not in a position to safely work on it, I have to pull into a parking lot or side street. This van coasts great in Neutral.

I know I have spark, because I placed my Leather man inside the spark plug boot, and got zapped. I was not touching the wire when I got zapped.

Today however I was going to replace the spark plug wires, when I noticed that the coil nipple, like on a sparkplug: was all chewed up. It had the feel like someone put a Vise-grip to it, and the wire from the coil to cap was a little lose.

I bought a new coil at advance for $13, when I removed the old coil, the nipple was heavily pitted, and missing the round shape it should have. I guess it was electrical erosion?

For the coil to get that way it must have been in contact with air ? is this true ?

So I think I might have solved the problem. I replaced the Coil and the wire going to the cap.
My troubleshooting experience tells me to do one thing and only one thing and see if it fixes it.

Lets hope it rains !!!!