2000 p71 smell

hi i have a 2000 crown vic 119000 sometimes out of no were there is a smell inside the car and it smells really bad all this happened after i got new cats on it can anybody help with this problem asked mahcanic but said fuel build up in cats thankz

If it smells like rotten eggs or sulfur it's the fuel being used. Try this.

1. Switch to a different brand of fuel and drive the vehicle for at least 100 miles. Monitor the decrease or increase in sulfur smell.

2. Do not add any type of 'fuel additive' as this could add sulfur to the fuel and cause/increase the odor.

3. Try to avoid extended periods of short trip driving or aggressive acceleration.

4.Request information from your local fuel dealers on the amounts of sulfur in their gasoline. Try to use fuel containing the lowest amounts of sulfur.

Hope this helps.
Franco

this smell only comes when i drive under hard acceleration which i dnt do any more and the smell isnt ther
thankz fo help Franco