Ford Thunderbird & a 2000 Mustang
Your Questions Answered about a 1994 Thunderbird and a Ford Mustang
Aug 5, 2007
Question: 1994 Ford Thunderbird
On a 1994 Ford Thunderbird, my hazard signals and brake lights quit working. I checked the fuse under the dash; it appears to be good. The question is, do the hazard flasher and brake lights run through the same relay? Please advise.
Thanks,
Mark Favors
Answer:
No, the brake lights and the hazard lights are on totally separate circuits. Your best bet would be to check all the fuses in the primary and secondary fuse boxes with a test light or DVOM to be sure they are, indeed, good. There is a good chance that you have 2 separate problems here.
Question: 2000 Ford Mustang 3.8 liter V-6
It was running good, then all of a sudden, it just started running real bad. Missing, hesitation pings real bad, and lacking enough power to get out of its own way.
It still had the factory plugs, but a new fuel filter. I pulled the plugs and found number 6 plug had a lot of carbon build-up on it, Their were no codes present.
Number 4 spark plug appeared to be wet with fuel. I changed all the spark plugs and number 4 wire and started the vehicle. I still ran bad, so I ran a decarbonizer with a small amount of water. It still ran bad.
This has dual exhaust with 2 40-series mufflers on it. The driver's side converter started glowing red, which means in most cases there is a lot of fuel going into that converter.
I pulled plugs to see what story they would tell. 4 was wet again. 5 and 6 not jet-black but signs of being a little rich. Cylinders 1, 2 and 3 looked great. I cracked number 2 spark plug pulling them out, so I bought 3 new plugs and replaced them. A mechanic told me a common failure on that car was the coil pack and he felt it was that, so I replaced it. The coil is not glowing now. It will idle now and sounds good when you raise to 2000 rpm, but it backfires when you accelerate, and if you try to put it in gear it pings and knocks and tries to die.
I unplugged the MAF. It did not make any changes. I removed the oil cap, and when it misses at idle sometimes you can hear a sucking noise, which makes me suspect a valve, but something else affecting the timing could cause that too, I think.
Do you have any ideas?
Answer:
Have the PCM scanned for codes again to be sure there are none stored. The Ford Dealer would be the best way to go. Ford has a lot of problems with their Mass Air Flow sensors getting dirty. For more information about this read Ford Expedition P0171 & P0174 for an explanation of the problem and a possible fix for it.
Assuming that's okay for now, then you will need to check for vacuum leaks. It sounds like you may have a big one and that will cause the engine to run too rich. After that you will need to do a fuel pressure test to see if the fuel pump is putting out the proper pressure and that the fuel pressure regulator is working correctly.
That’s all for this week. Feel free to browse the archives for past topics. And, as always, if you are stuck and need an immediate answer you can always call Vince on the phone.
