1987 Ford Taurus Failed smog

SUSAN P

MEMBER
1987 FORD TAURUS
6 CYL
2WD
AUTOMATIC
143,000 MILES

My vehicle had passed a smog test just a few hundred miles ago, but then was not driven for about 7 years. Now it is a Gross Polluter. I changed spark plugs, re-set timing, changed oil, cleaned EGR & Oxygen sensor, put fresh fuel in and drove it for a few hundred miles prior to testing. Readings are:

HC NO
15 mph Max112 (285) Max 778 (2198)
25 mph Max 86 (292) Max 717 (2667)

The car runs great, gets good mileage, has lots of power, sounds good, and no codes show up when scanned. Can you tell me what I should check/replace next?

Thank you,
Susan P

3 Replies

PACECLASSA

MEMBER
39 POSTS

Just a guy with a '95 Taurus and not a mechanic, but none answered you so I will give it a shot.

Mine failed emissions and was running "hot" also. I checked thermostat, o2 sensors, MAF sensors, etc. And it was not any of those. I cleaned all the filters, gave it an oil change and ran some engine cleaning stuff through the throttle. Nothing. Replaced all the vacuum hoses (they needed to be replaced badly). It only helped a little.

Replaced the catalytic converters (my car has two) and that solved it.

The stuff up top I did myself and it was cheap. The catalytic converters. A shop and it was a little bit more expensive.

I hope this helps you.