1989 cadillac deville service engine light on??

bklynsoulja · #1 (**permalink**) 01-05-09, 07:32 PM

hello, i am wondering what can it be when my service engine light comes on after an steady speed of around 65-70 on highway, it only pops up if i drive fast i believe well only happen on highway for me...i kno my cat converter is dieing due to hitting it and it rattles and today i experience the freakin rotten egg smell for the first time so sad can it be my o2 sensor and my cat converter? cus i also got very bad milage (9 mpg) i got 152000 miles on my car

chubbyranger · #2 (**permalink**) 01-05-09, 07:41 PM

Your symptoms are consistent with a bad cat - I replaced mine much sooner on my 1990. Pull codes ('Off + 'Warmer' on the climate control), watch the Fuel Data Center, and you may get some more clues.

bklynsoulja · #3 (**permalink**) 01-05-09, 08:04 PM

i aciddently deleted all my history codes (yes dumb me) and now im on the guessing game...i think i got a bad cat and o2 sensor, i am deciding to replace them both soon

bklynsoulja · #4 (**permalink**) 01-06-09, 12:17 AM

does any1 know if a 89 have a fuel pressure regulator?

chubbyranger · #5 (**permalink**) 01-06-09, 07:55 AM

If the light is on you will have a current code - codes go with the light and you shouldn't get one without the other. A PFI motor should have an FPR, not sure about TBI.

bklynsoulja · #6 (**permalink**) 01-06-09, 12:52 PM

so the next time i get the service engine soon light on i should check for the code?

noahsdad · #7 (**permalink**) 01-07-09, 01:28 PM

Yes. This could also be EGR related.