1992 Mazda Protege Emission failing

Tiny
TEO
  • MEMBER
  • 1992 MAZDA PROTEGE
  • 4 CYL
  • FWD
  • MANUAL
  • 180,500 MILES
I have a 1992 Mazda protege 1.8L Manual Transmission. First Emission test HC Cruise limit 170 pass at 98, Idle limit 220 pass at 198. CO Cruise Limit 1.2 pass at 0.33, Idle limit 1.2 failed at 1.79.
After I replace spark plus (found one cracked when I took it out), replace Rotor and Distributors. I did not replace Wires, they are fairly new-3 years and in great condition.
But second test result got worse:
HC Cruise limit 170 pass at 31 --much better, Idle limit 220 failed at 223.
CO Cruise Limit 1.2 pass at 0.09 --much better, Idle limit 1.2 failed at 2.53.
Both idle condition are much worse. I drive (at 9am) to the test center about 5 miles from my home after I replace the parts a night before.
What do you think the problem is and can I be able to fix it myself or get a teachnician to fix it?
Thank you very much for your help.
Saturday, June 14th, 2008 AT 12:21 PM

3 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Hi teo,

Did you check the ECU for any codes? Is the O2 sensor ok?

Idling being rich, give the throttle body a good cleanup with carb cleaner. Check TPS setting.
Was this
answer
helpful?
Yes
No
Sunday, June 15th, 2008 AT 10:02 AM
Tiny
TEO
  • MEMBER
  • 2 POSTS
Hi KHLow,
Thanks. What is ECU. Where is O2 sensor located, how do I know it is good?
Where are you referring to is trottle body. I know this has no Carburator. What is TPS and where to find it?
Sorry, I really do not know about the car except changing oil, filter, plugs, wires, and dist cap.
Thanks.
Was this
answer
helpful?
Yes
No
Monday, June 16th, 2008 AT 1:26 AM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
Hi teo,

ECU = Engine Control Unit (computer) If you cannot get a scan, you need to manually get the codes with a LED bulb or voltmeter.

O2 sensor is plugged into exhaust.

TPS = Throttle Position Sensor, found on the throttle body
Was this
answer
helpful?
Yes
No
Monday, June 16th, 2008 AT 6:23 AM

Please login or register to post a reply.

Sponsored links