Rough idle random misfire and hesitation when acceleratin...

Q: Rough idle random misfire and hesitation when accelerating

asked by on November 03, 2017

Rough idle, random misfire, and hesitation when accelerating; new plugs and wiring, just did oil change,cleaned throttle body, and Mass air flow sensor. I gave fuel treatment and engine restorer, which there is definitely improvement but still having issue; any suggestions????

My car has 151000 miles.
My car has an automatic transmission.

Hi Brandon. Thanks for contacting us tonight. If you were having these same symptoms prior to the services you completed, then I would assume that either you’ve got a misfiring or clogged fuel injector or a distributor (ignition coil) that is worn. If these symptoms have popped up after the service, I would double check your spark plug wire connections (making sure they are attached to the correct plug) or check for a vacuum leak. A loose electrical connection to the crankshaft position sensor can also be a cause of these type of symptoms - as could ECU issues. In worse case situations, damaged valve springs and other cylinder head components. You might want to have a professional mechanic help you diagnose this issue.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Code P300. Tried fixing with no success.

When you receive the OBD code P0300, it means your Buick LeSabre is experiencing a random misfire. This code is given because one or more of the engine’s cylinders are misfiring. While our first instinct is to think spark plugs,...

Stall while idle or coming to a stop replaced IAC MAS and TPS due to codes still same issue

Hello, and thank you for writing in. With the codes you are pulling, and the replacements you have already made, you are likely dealing with an issue pertaining to the the throttle itself, or the idle air control valve gasket....

The heater, radio and rear defroster stopped working. Check all fuses and they were fine. what else could it be?

If all of these issues began at the same time, it is possible that you have a bad ignition switch. Heat, Air Conditioning and I believe the radio are only powered with the key in the ON position. They will...

Related articles

The Best Used Cars to Buy That Can Be Towed Behind an RV
Summer Summer is a great time for a road trip, but often travelers like bringing all the conveniences of home along, in the form of an RV. Then they tow their car behind it – sometimes this practice is called...
A Buyer's Guide to the 2012 Buick Regal
The The 2012 Buick Regal is definitely not the Regal of yesteryear you may have heard your grandparents fawn over. This mid-size sedan has a lot of modern features that start at the engine and stretch all the way to...
The Best Used Cars to Buy If You’re an Architect
Obviously, Obviously, architects appreciate beauty and symmetry. This is not just the case when it comes to their building projects, but also in terms of the vehicles they choose. We have evaluated several used cars, and identified the Mercedes...