E350 engine misfire only with lights on
Thread Starter
|
Freshman User
Joined: May 2008
Posts: 26
Likes: 0
E350 engine misfire only with lights on
This somehow ended up in the wrong forum.
I have a 1989 E350 with 460ci engine & C6 trans. It runs fine unless the parking lights or headlights are turned on. With lights on two cylinders drop out. If I give it lots of gas one of them will kick back in leaving one cylinder misfiring but back to cruise and two cylinders die. With lights off all cylinders run all the time. BTW, this van has quite a few marker lights so the light draw is somewhat higher than most vans.
All the ignition components are relatively new.
I checked voltage at the "downstream" side of the main accessory breaker (mounted on chassis near battery) to ground with engine running it holds a constant 13.8v with lights on or off. With the engine off it measures 12.8v with lights off and 12.4v with lights on.
Ideas?
I have a 1989 E350 with 460ci engine & C6 trans. It runs fine unless the parking lights or headlights are turned on. With lights on two cylinders drop out. If I give it lots of gas one of them will kick back in leaving one cylinder misfiring but back to cruise and two cylinders die. With lights off all cylinders run all the time. BTW, this van has quite a few marker lights so the light draw is somewhat higher than most vans.
All the ignition components are relatively new.
I checked voltage at the "downstream" side of the main accessory breaker (mounted on chassis near battery) to ground with engine running it holds a constant 13.8v with lights on or off. With the engine off it measures 12.8v with lights off and 12.4v with lights on.
Ideas?
Post Fiend
Joined: Jun 2002
Posts: 13,873
Likes: 3
From: Atlanta GA
> runs fine unless the parking lights or headlights are turned on.
The headlamp switch is probably being overloaded.
It might not be so easy to disconnect the marker lights in series, so see what happens when you pull all the bulbs and if it misfires with the bulbs out and only the marker lamps on. This would help eliminate a bit that they are wired wrong.
Yours is EFI EEC4 with the TFI module, correct?
The headlamp switch is probably being overloaded.
It might not be so easy to disconnect the marker lights in series, so see what happens when you pull all the bulbs and if it misfires with the bulbs out and only the marker lamps on. This would help eliminate a bit that they are wired wrong.
Yours is EFI EEC4 with the TFI module, correct?
Thread Starter
|
Freshman User
Joined: May 2008
Posts: 26
Likes: 0
The headlight switch is about a year old. I replaced it when the lights became intermittent. The load is less than when I bought the truck since I replaced a pair of taillights with LED a couple years ago, but all the marker lights are still incandescent. The marker lights are all original but this is a Lewis conversion 17 passenger van. I haven't added any more.
It is EFI with OBD-I so I assume it is EEC4. The computer was replaced with a revised FORD unit to correct some original programming issues with power loss.
It is EFI with OBD-I so I assume it is EEC4. The computer was replaced with a revised FORD unit to correct some original programming issues with power loss.
Thread
Thread Starter
Forum
Replies
Last Post
