I have a 97 Expedition and I replaced the alternator, but now it's misfiring. The spark plug wires are all tight and it seems like all the connections are good. I had the Check Engine light come on also. I took it to have the code scanned at AutoZone and it came back with a misfire code.
When I drove it before I replaced the alternator, It completely shutdown and the headlights went real low. Could this have messed up the computer in any way?
Thanks guys!
2007-12-05 09:43:16 · 4 answers · asked by Jason M 2 in Cars & Transportation ➔ Maintenance & Repairs
First, check if the plug wires are still in sequence. some vehicles have specific orders in which the plug wires go. Next pull your plugs and make sure the points are clean. (the part that goes into the cylinder, not the top) Other than that, they make cars now specifically so you have to go to a shop with a diagnostic (OBD2) machine. It's unfortunate, but the way of the world. I hope I could help.
2007-12-05 09:51:49 · answer #1 · answered by Quigi 2 · 1⤊ 0⤋
Anything is possible, but not likely. Remeber that for the engine to run properly, all voltages need to be stable. Your spark plugs and fuel injectors will not work correctly if there is low voltage power supply. Is your battery new or old?? Sometimes a bad battery will drain the power away from engine functions, and draw the power to itself instead of supplying ample power to injectors and plugs. It is also possible that the replacement alternator was improperly rebuilt or has a regulator problem diverting the power away from the injectors and wires. Have your charging system evaluated for proper voltage.
2007-12-05 10:02:30 · answer #2 · answered by Robert M 7 · 0⤊ 0⤋
I drive a GM (Olds) but I believe that loss of battery power can screw up the computer. I've had to disconnect my battery twice (once while installing my stereo, once while replacing the timing chain and tensioners), and both times my spedometer would constantly read 140 mph after reconnecting the battery. It would show this reading until I got it up to 70 on the freeway. Sounds like your misfiring problem might be related to the initial loss of battery power as well. I would run a complete diagnostic.
2007-12-05 09:49:16 · answer #3 · answered by justme 4 · 0⤊ 0⤋
check to make sure you got the correct AMP alt. installed. this could cause a "surge' in your electrical track.
2007-12-05 10:06:42 · answer #4 · answered by † God Bless You † 3 · 0⤊ 0⤋