1998 Mazda 626 Fuel Pump? TPS? Stutter.

Tiny
ROBIN55109
  • MEMBER
  • 1998 MAZDA 626
  • 6 CYL
  • FWD
  • MANUAL
  • 12,900 MILES
My daughter has a 98 626 with the 2.5L V6. When driving it likes to hesitate or stutter. This only under constant speed when accel and decel it doesn't seem to do it. It has gotten worse in the last week and if you run down the highway with the cruise at 80 it's not so bad. Try to hold it to 60 and it will buck and stutter in not a rythmic way. It just does it here and there. Not only that, it runs out of gas at 1/4 tank on the gauge. At first I was thinking TPS (Throttle Position Sensor) or Idle Corntol Unit. Now I am thinking fuel filter. With all of these being way over 100 clams I would like to see what you guys think. I have tuned up and checked MAF as far as it being clean. I have also notice that when it stutters the tach niddle does not drop for that split second so I am not thinking electrical. We did run codes on it and found a O2 sensor fault but I am wondering if I am getting that once in awhile because of the stalling?
Do you
have the same problem?
Yes
No
Monday, April 13th, 2009 AT 3:38 PM

3 Replies

Tiny
RASMATAZ
  • MEMBER
Could be the oxygen sensor and the rest below

Dirty fuel injectors (cleaning the injectors often fixes this).
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)

Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include:

Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires
Was this
answer
helpful?
Yes
No
Monday, April 13th, 2009 AT 4:51 PM
Tiny
ROBIN55109
  • MEMBER
Actually it isn't a miss. It is like someone shuts it off for a few seconds and then back on again. Plugs and wires are brand new. Checked coils they seem fine. Nothing should be wet or at least it would be dry by now. I also meant to say fuel pump not filter. If I bought a Chiltons or Haines manual for this car would it tell me how to check these componants? One other thing it does once in awhile is surge at idle. It will go from 750rpm to 1500 and back. The tune up helped this alot but it still does it once in awhile. Any more ideas? Thanks for you time.
Robin
Was this
answer
helpful?
Yes
No
Monday, April 13th, 2009 AT 5:07 PM
Tiny
RASMATAZ
  • MEMBER
Check and test the camshaft and crankshaft sensors
Was this
answer
helpful?
Yes
No
Monday, April 13th, 2009 AT 5:21 PM

Please login or register to post a reply.

Recommended Guides