Jumpy Acceleration, check engine
 

I rencently bought a 1997 Protege LX 1.5l Auto with 120,000 miles on it. When I got it the check engine light was on, and a friend of mine at the Mazda dealership checked it on the computer and told me I needed a new catalytic converter.

He cleared the code and I drove about 1,000 miles. I changed the plugs and wires, and it drove fine.

Now the check engine light it on again. Autozone said I needed front oxygen sensor.

Now the car hesitates and then jumps when I accelerate from a stop. I have been roud the bend with this kind on thing on a couple 93-99 626 LX Autos, so of course my first fear was the transmission. But I have been assured the Protege does not have this chronic condition.

I have also observed a drop in fuel economy of about 20% since the acceleration problem started.

Will the oxygen sensor fix this?

RE: Jumpy Acceleration, check engine
 

if your cat is bad....it causes a blockage in your exhaust, thus backing up excessive heat, which can make O2 sensors go bad...i would have someone really look into your cat being good or bad..saty an exhaust shop...if not..try the front sensor....

RE: Jumpy Acceleration, check engine
 

I AGREE 100% WITH PATRICK-IF THE CAT IS FOULED THEN THE O2 IS PROLLY BURNT TOO

RE: Jumpy Acceleration, check engine
 

find a infared thermometer,it shoots a lazer ,some parts stores carry them (raytec) makes them, take the temp of the exhaust going in to the convertor {in front of it} with the engine warm , then take the exhaust temp on the outlet side of your convertor 2 inches behind the convertor if there is a big difference in the 2 temps ( alot higher temp in front of the convertor} then you convertor is bad

RE: Jumpy Acceleration, check engine
 

Also check the air intake hose for cracks. this is a common problem.
Marshall

RE: Jumpy Acceleration, check engine
 

I emailed you.
Had the same problem. Your mass airflow sensor needs to be cleaned or replaced. Try cleaning it first. I used some electronic spray from Autozone for six bucks. Now it runs perfect. I thought I was going to have to sell the car because I couldn't figure out the problem. This fixed me right up. Goodluck.

Mike

RE: Jumpy Acceleration, check engine
 

I doubt randolphpat is still looking as it was the only post made back on March 17. If he is then there is a possibility that may be the problem. I had a 98 with the 1.5l and about 100k miles in a few months ago that had a similar complaint. Bad hesitation from a stop or accel from closed throttle about 1/4 of the time when hot.. Oxygen sensor had been replaced with a cut and splice Bosch due to a front end accident. Sensor signal voltage was stuck at a steady 750mV. No fluctuations. I did not think that should have cause the hesitation but decided to replace anyway as it was obviously defective and sure enough the hesitation was gone and has not been back since. But you are also right in that the MAF could be at fault too. Depends on what kind of code was stored.

RE: Jumpy Acceleration, check engine
 

I had a p0171 code, along with what felt like a lot of missing during acceleration and especially when maintaining speed on the uphill. Also, the car stalls at startup in the morning, but not at other points throughout the day, and the car has had a significant loss in overall power. I replaced the MAF sensor, as mine was coded prior to July of 2000, and that got rid of the CEL, but not the driveability issues. I also replaced the plugs.

Does all of this sound like it might fall under the same category of O2 sensor? How do I check the coil packs for spark on a 99 protege?

Thanks for the feedback...

RE: Jumpy Acceleration, check engine
 

I have a '99 Protege 1.6L LX and I have the same problems. The car shakes a lot when accelerating from stop in first gear, and sometimes when I put it into second. It just started a few weeks ago, in semi-cold weather, but it still does it in warm weather. My check engine light is on and I got the following two codes from advanced auto: P1141 Fuel Air Metering, P0171 System Too Lean - Bank 1. I cleaned my mass air flow today but the light came back on while driving a little while ago. I am also suffering from loss in overall horse power. Any suggestions??