Possessed '05 Expy?

[red-russian1]

On our way home from the in-laws yesterday, we ran into heavy rainfall that lasted about 90 minutes. Shortly after the rain started, the engine began to miss and the CEL started flashing. Eventually, the CEL turned on solid. About an hour down the road, the security alarm started going off. The only way I could silence it was to cut the wires going to the siren. So, we got home, I shut the engine off and pulled the keys but the door/headlight/key in the ignition dinger wouldn't stopped dinging. The only way I could get it to stop was to turn the headlight switch to AUTO. Well, 30 minutes later my wife says the park lights were still on. Only thing I could think to do was pull the battery cable. I waited 15 minutes, reconnected it and everything works fine again. Anybody have any ideas?

Sent from my LM-G710VM using Tapatalk

 

[Cooper]

I don't know about the alarm going off. But when I first bought my 03 XLT...
Everytime it would rain heavy it would run rough and a few times the cheak engine light would blick.
I put in new plugs, coils, and O2 sensors and it have never did it since.
I was stabbing in the dark but it worked.

 

[Hamfisted]

If it only happens when you encounter heavy rain look for signs of water under the hood, and inside behind the passenger side kick panel ( the security module and fuse box location...). Check the condition of the hood to firewall weather gasket. Are you the original owner ? How does the windshield seal look ? You may have problems at a few areas and the heavy rain just ties them all together for that symphony experience. You have a separate siren for your alarm? Usually it's just the vehicles horn that honks during alarm mode. An aftermarket security system could introduce a whole problem in itself.









This windshield support under the cowling is known to leak as well .... this is the area above the fusebox

 

[red-russian1]

If it only happens when you encounter heavy rain look for signs of water under the hood, and inside behind the passenger side kick panel ( the security module and fuse box location...). Check the condition of the hood to firewall weather gasket. Are you the original owner ? How does the windshield seal look ? You may have problems at a few areas and the heavy rain just ties them all together for that symphony experience. You have a separate siren for your alarm? Usually it's just the vehicles horn that honks during alarm mode. An aftermarket security system could introduce a whole problem in itself.









This windshield support under the cowling is known to leak as well .... this is the area above the fusebox

I looked under the hood but couldn't find any wet connections. I didn't even think to look behind the RH Kick panel. I'll have to take a look at it tonight. I am not the original owner. I will have to take a look at the windshield seal also. As far as the separate siren, I thought it was Factory. It appears OEM anyway. I can take a picture under the hood when I get home. Also, this is a 2005 Eddie Bauer with remote start.

Sent from my LM-G710VM using Tapatalk

 

[trhymers]

On my 03 water was getting into the harness in the drivers side rocker panel. There is a purple wire that got corroded and was causing all sorts of electrical issues like you describe. Just take that plastic rocker panel cover and look at the wires in there. Confirm there has not been water getting in there. https://www.fordf150.net/forums/viewtopic.php?t=54294

 

[AftonJay]

Is your remote start fob the OEM or an aftermarket? I am thinking maybe your alarm and start are aftermarket, and that may be part of the problem. The actual drivability issue you had with the rough running and CEL light, are consistent with plugs and or coils. the other stuff may just be bonus issues due to aftermarket system.

 

[98eb5.4]

a flashing cel indicates a misfire & code tells which one

 

[red-russian1]

Is your remote start fob the OEM or an aftermarket? I am thinking maybe your alarm and start are aftermarket, and that may be part of the problem. The actual drivability issue you had with the rough running and CEL light, are consistent with plugs and or coils. the other stuff may just be bonus issues due to aftermarket system.

As far as I know, it is OEM. We've only owned this thing for about 1 1/2 years. I did plugs and coils about a year ago. FUN TIMES!

When I connected O'Reilly's Bosch code scanner on Saturday, it showed 3 transmission codes but no engine codes. Originally I had disconnected the battery for about 15 minutes in order to get the security system to reset. So I'm guessing I probably cleared the CEL codes.
And the engine is still missing. I ordered a code scanner last night so I will have to see if I can find out which cylinder is misfiring. I've got to put it up on jacks tomorrow night to change oil and locate an exhaust leak so I'll check it out then.


Sent from my LM-G710VM using Tapatalk

 

[Mad Oshea]

all the expis will leak at the wind shild, and into the box behind the fuse cube. Then go hay wire. seal the wind sheild again, and watch it stop.

 

[98eb5.4]

as far as the park lights staying on, not sure about gen2 but there is a known issue out there related to tow package wiring,

i just pulled the trailer park lighting circuit fuse under the hood on my 98