A recall would be among the largest in history -- Ford installed the switch in every Ford vehicle built between 1984 and October 1992.
Based on the current cost of $50 to $90 to replace the switch at a Ford dealership, a recall of all 23 million vehicles could cost Ford up to $2 billion.
Ford has recalled 248,000 cars and trucks with the switches in Canada, and the U.S. government's auto safety agency is investigating whether an electrical short in the switches can cause steering column fires without warning.
``We have not seen the incident rates here that we saw in Canada,'' Ford spokeswoman Francine Romine said.
``We have found that a short has been happening in some of the ignition switches, but we're not ready to say that it is defective,'' she said.
Romine said Ford received reports of 300 steering column fires in Canada, two-thirds of which were caused by the switch, out of the total 248,000 vehicles recalled.
In the United States, Ford has received reports of 800 steering column fires, but out of a much larger population of vehicles. There are about 4 million vehicles on the road of the same model and year as those experiencing fires.
Many types of vehicles equipped with the switch have experienced no reported problems, Ford said.
``We need to look at every single incident'' before determining whether further action is warranted, Romine said.
But Donnetta D[...], of Muskego, Wis., is angry that Ford won't recall the cars. She said her husband, Harold, narrowly escaped with his life when his 1990 Ford Tempo caught fire on Feb. 2, and she blamed the ignition switch.
``There were sparks flying out from under the dashboard right at him,'' she said in a telephone interview. ``I'm scared to death of any Ford product now. I will never touch one again.''
The Ford vehicles recalled in Canada include the 1989-90 Escort, 1989-91 Mustang, 1990-91 Thunderbird and Mercury Cougar, 1988-89 Crown Victoria and Mercury Grand Marquis, 1989 Lincoln Town Car, 1989-91 Aerostar minivan, and 1990 Ford Bronco and F-Series trucks.
Ford is currently advising U.S. customers to replace the switch at their own expense if they are concerned about it. The new switch has terminals spaced farther apart to prevent a short circuit from occurring if a plastic insulator between the terminals deteriorates.
The National Highway Traffic Safety Adminstration continues to study the problem, but has not recently made any announcements about the probe. The issue received renewed publicity after story in USA Today's Tuesday edition.
NHTSA spokesman Tim Hurd said the agency began investigating the switches in 1990 model Ford Escorts in November 1994. He said the problem is potentially serious, but the agency has not determined whether there is grounds for a recall.