1999 Ford F-150 blown spark plug. I replaced the spark plugs on my F-150 approximately three months ago. I replaced the original plugs with autolite double platinum plugs. Yesterday (June 13, 2004) while accelerating from a stop light, I heard a loud bang from under the hood. Luckily I was only about a mile away from home. Once there, I raised the hood and found that the number two spark plug had been blown out of the cylinder head. It destroyed the coil pack as well. It appears that when the plug blew, it shot up into the coil pack thereby destroying the coil. Since the ignition wire is part of the coil pack, it further appears that the compression of the rubber insulator acted like a spring and pushed the plug back into the oriface with enough force to break the white insulator at the bottom of the plug and and slam the tip into the electrode. I was able to remove the plug without incident. I did not find any remnants of aluminum in the spark plug threads. Since the plugs were changed only a few months ago, I still had the old plugs. The damaged plug was replaced with one of the old plugs. The threads felt as though they were still intact, and I was able to get the replacement plug back in without any modifications. It was tightened down, just snug, not tight. The coil pack on that cylinder had to be replaced. The cost from autozone was approximately $45. I will continue to watch and listen for any tell-tale signs of the plugs backing out as described on the F-150 web page. I do recall a "ticking" noise about 2-3 days prior to the incident.

- Houston, TX, USA

Digital odometer light turns on & off. Door ajar light, dome light, and automatic door locks go on & off also. Electrical problems may be the "GEM module." Seat belts do not retract getting cut/damaged from door latch when door is closed, they have been replaced once already. Ford engineers were notified nearly six months ago but no reply.

- Shelley, ID, USA

Door switches for lights fail to turn off interior lights, have seen same problem with several other truck of same year.

- Paris, TX, USA

Water was getting down into the dashboard and causing windshield wipers to stop. The windshield wipers work normal when the vehicle is in neutral or park. The wipers would only work on low, the radio would cut off when driving in the rain which would happen after 10 minutes, the vehicle wouldn't turn over. The diagnosis was that harness assembly needed to be repaired at the starter assembly. There was a clicking sound coming from under the dash, and the theft light flashed. The mechanic found a bad GEM module which also caused the blower to stay on and drain the battery. The heater bower wound not shut off intermittently when shutting the trunk off and had to be manually shut off.

- Brunswick, OH, USA

Spark plug blew out of head, stripping threads from head. This is the second one for this vehicle. The first was in June of 2002.

- Anchorage, AK, USA

While driving spark plug blew out of the cylinder head and a loud noise was heard. The noise startled the driver who lost control of the vehicle momentarily. The cylinder head was replaced.

- Winona, MN, USA

July 2003 my electronic odometer blinks out. I have had to tap the glass to ge tit to come back on this is usually when 1st starting the truck. Now the odometer will blink out while I am driving and then turn back on. I have on 67,000 miles. Plus the driver side window motor is making a grinding noise when the window is going up. Also October 31 the gear shifter will no disengage while I am applying the brake to go from park to reverse.

- Huntington Beach, CA, USA

Ford F-150 lightning spark plug blow out.

- Houston, TX, USA

Spark plug blew out of number three cylinder. Cost between $1900 to 2000 to repair.

- Perham, MN, USA

While backing out of a parking space at 8 mph the vehicle suddenly accelerated backwards up to 60 mph. The shifter was moved drive and the vehicle continued to accelerate forward. The brakes would not stop the vehicle. As a result the vehicle slammed into an embankment. Vehicle was taken to the dealer where the replaced the mass air glow sensor and throttle assembly. The bed of the truck was pushed outward on the passenger side. The dealer cleaned and lubed the latches. The passenger side striker was shimmed and adjusted.

- Bowling Green, IN, USA

Consumer states electrical system failed. Dealer notified.

- Eglin Afb, FL, USA

3 spark plugs on my 99 F150 have backed themselves out, causing immediate engine decompression. The only way to adequately repair is to completely remove the head, a multi-day, multi-dollar task. Viewing auto message boards suggest I am not alone in this experience. Apparently there is some defect in the Triton V8 engine design, although my research shows Ford has not addressed this issue.

- Blairsville, GA, USA

I bought the 99 F-150 used. I've owned it for 2 years and in those two years spent over 3000 dollars repairing it. I cant handle the thought of keeping a truck that cost so much in repairs. And now the dealer tells me I need a new transmission. This is one week after I spent over 500 replacing the spark plugs, fuel filter, and getting the fuel injectors cleaned. I have only 58,000 miles on the thing and was told by the dealer that the plugs don't need to be touched for 100,000 miles. Well it was missing and that was the problem. The truck slams into gear between 1 and 2, and now the problem is my transmission is bad. At 58,000 miles" and I've never even towed anything. Just regular wear and tear" I think these trucks must be lemons. After I get the transmission fixed, I'll have spent $5,600 in a two year span. I have to sell it because the repairs are more than the payment. I guess that's why it was sold to me when it was only two years. Old.

- Grand Rapids, MI, USA

My family and I were traveling on the interstate when our gauges on our truck began to go from zero to one hundred miles per hour back and forth. Our gas gauge would from full to empty. All gauges on the dash would go crazy. Our battery light had come on a few miles before this occurred. We lost all power and our truck decelerated quickly on the interstate. We found a parts store and put on a new alternator and battery thinking that would do the job. As we continued our trip, the gauges began to do the same thing within ten miles of changing alternator and battery. I would like to know if there is a flaw in 1999 Ford F150's. we checked all fuses and have no idea why this occurred. The truck cannot be driven because it will shut off while driving.

- Southaven, MS, USA

I own a 1999 Ford F-150 lariet and the power locks are malfunctioning on both sides. I have a neighbor with a 2001 F-150 and he has the identical problem. The locks work at times and then don't at others. I am only at 45000 miles and am out of warranty but wanted to know if this is a Ford recognized flaw.

- Douglasville, GA, USA

Consumer states the circuit board on the vehicle has malfunctioned causing the brake lights to stop working. Contacted dealer and the dealer is aware of the problem but have no rememdy.

- Shaker Heights, OH, USA

Truck was unstable with cause unknown by dealership. Owner has taken vehicle in for corrective action several times, however nothing has changed. Vehicle vibrates excessively when at idle with RPM gauge fluctuating up/down. Consumer states that the engine runs rough, oil level dropped and there was a clicking noise in which the dealer replaced the fan blade and fan clutch. Rear brakes experienced grinding, dealer applied a silencer to the front and rear brake pads. Consumer has experienced several problems with the A/C and heater, problems still exists. Vehicle uses a lot of gas, idles rough and experiences small hesitation upon acceleration. Vehicle kicks into gear. Vehicle drifts to the right, while driving at higher speeds, vehicle and steering wheel vibrate. Driver side rear view mirror rattles when closing door, when everything is closed there is an outside noise, dealer resealed the windshield. When turning on the lights, the clock and A/C are delayed. There is a whining noise when turning steering wheel. Window control buttons stick at times, dealer replaced the window switch.

- Miami, FL, USA

Door ajar indicator stays illuminated. Interior and cargo lights stay illuminated although doors are shut, also drivers side door is the only one that is used. Problem has been going on for 3 months.. consumer also stated if the key is in the igniton the bell will go off.

- Cumberland, IA, USA

Faulty electrical wiring causing erratic operation of different parts in vehicle, such as power windows do not to work properly and cause the motor to overheat/ no brakes/no tail lights and malfunctioning of cruise control. Vehicle been in the dealer shop on two occasions, problem still has not be resolved, and vehicle still in the dealer shop. Dealer would not give consumer a loaner until they can correct the problem. Can NHTSA help or provide additional information on this matter.

- Atco, NJ, USA