How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Drew Your Own Question
Drew
Drew, Super Mazda Tech.
Category: Mazda
Satisfied Customers: 2518
Experience:  19 yrs. experience. Mazda Senior Certified Tech, with Ford, Linc. & Merc. experience. ASE L1 Advanced Certified Master Tech.
49548721
Type Your Mazda Question Here...
Drew is online now
A new question is answered every 9 seconds

98 Mazda: rough idle..stop light and pulls the car..high way..needle

Customer Question

98 Mazda rough idle jumps rpm when at a stop light and "pulls" the car and feel it on the high way too "pulls" a lot and rpm needle jumps . Any suggestions? Thanks
Submitted: 5 years ago.
Category: Mazda
Expert:  Drew replied 5 years ago.

Welcome to Just Answer. My name is XXXXX XXXXX I will be glad to assist you.

 

Sounds like you may have a few different concern going on here.

 

Inspect to make sure the check engine light is not on and no fault codes are stored in the computer.

 

With the engine running, look/listen under the hood for any sign of a vacuum leak. Inspect the air hose between the air filter and engine throttle body for cracks.

 

If the engine runs smooth on accelerating from a stop, the fuel, and ignition system should be good. If it lacks power and runs rough during acceleration, you should replace the ignition coils, plugs and wires.

 

If the engine has a idle concern at stop light, you will need to remove and clean the throttle plate, throttle body and idle speed control valve. If idle is still low/high or stalls, replace the IAC valve. (#2 and #9 in diagram.)

 

If the engine has a vibration at idle, I suspect a broken engine/trany mount. You will need to remove and inspect all mounts for wear/damage and replace as necessary.


Please let me know if you have any additional questions by hitting the reply button.

Thanks
Drew

 

graphic

Customer: replied 5 years ago.
No check engine light. And it started doing that 2 weeks ago and it acts up about every 10-15sec it "pulls/sputter" when at a stop sign/ driving. Acceleration seems fine.
Expert:  Drew replied 5 years ago.
If the engine has a idle concern at stop light, you will need to remove and clean the throttle plate, throttle body and idle speed control valve. If idle is still low/high or stalls, replace the IAC valve. If it also does it while you are driving down the road at any speed, also try cleaning the mass air flow sensor. (MAF)

 

Thanks
Drew

Drew and 5 other Mazda Specialists are ready to help you
Customer: replied 5 years ago.
I just cleaned those parts and didn't do anything. But I left the car running and noticed ticking/spark sound coming from the distributer cap and very time it ticks it makes the engine vibrate/ bog down and the rpm needle moves too
Expert:  Drew replied 5 years ago.
Looks like you found the misfire that should be causing your concern.

Thanks for the accept.

Drew
Customer: replied 5 years ago.
Do I replace the distributor cap? And wires and spark plugs? Or just the cap? Thank you very much for your help Drew
Expert:  Drew replied 5 years ago.
If it has been more then 30k miles since you last replaced any of them, I would replace plugs, wires, cap and rotor to keep the ignition system operating properly.

If spark plugs are newer, just replace wires, cap and rotor.

Thanks
Drew