2001 F150 Crew 4.6L w/ AT. Vehicle starts - no problem and sounds normal, but ABS light stays on (1st time ever the light has stayed on). Apply brake to shift into drive - engine shuts down. Also, when in park idling, if you turn on lights the RPMs drop 200-400 and starts to sound rough.

Talked to Ford garage and they are confused.

Any help would be appreciated.

 

Welcome to the site..

Good one.. When idling in Park, is your foot on the brake when the headlamps are turned on? Does the engine stumble, run roughand die with the shift, or does it shut down like with the switch?

 

Engine will not start with foot on brake; you can sense that it wants to turnover, but just won't. Take foot off brake and it starts just fine. The vehicles headlights are always on. ABS light stays on.

Apply brake and engine shuts off - just like a lightswitch.

Restart engine and let idle with no brake. Turn on driving lights. RPMs down 200, idles a little rough. Tail lights are bright. Turn on headlights. RPMs down another 200, idles rougher. Tail lights are extremely dim. Turn high beams on - taillights appear to be out. Turn high beams off. Tap brakes - just on/off. Engines stumbles big time - never dies. Headlight flash off then on. Engine then resumes normal idle.

Disconnect ABS on rear differential. Run same sequence with same results.

Since this seems electrical, I check all fuses in both use boxes. All appear to be fine.

Thanks.

 

So I pulled the fuse and tried to drive to the nearby Ford dealer. Had problems moving the vehicle from a standstill. Everytime I took off, the engine stumbled, rumbled, and died a slow death. Finally able to baby it through the stumbling process and get to the garage.

They had about a dozen codes pop up and then further tested the ABS, fuel pump, alternator, etc. But everything checked out. They concluded that is was a grounding problem. Two more hours of tracing things out and they found that the ground bolt behind the drivers headlamp had broke off / fell out and created this situation. This is located between the headlamp and the radiator overflow reservoir. Replace bolt and it runs like a champ. $362.00.

Hope this helps somebody.

 

Thanks for the update and fix post..

 

same thing happened to my 05 4.6 4x4...took it to the ford place and they put a whole new throttle body on it and it runs great after about 300 bucks.