New answers tagged

0

Bad ignition coils or spark plugs would be my first guess. Low voltage to the coils or if timing is off could also cause misfires. I just looked up 2012 corolla and you have a timing chain, not a belt. I doubt you would need to replace it. Get your battery tested (many stores do it for free). If you're mildly savvy with a screw driver, you can swap an ...


0

If you want to change your battery, that would be easy enough to do. But take note that there may be a radio code you need to know after replacement. Your best bet is to have the timing belt done by your repair shop and have them diagnose the misfires. But before they do the timing belt have them check the integrity of the engine via a compression test so ...


2

My car misfired for years with audible ping, sometimes quite badly, without any check engine light (CEL). It wasn't until I soaked the engine with Seafoam for several days that the dashboard light suddenly appeared. As it turns out, there was a leak around the PCV valve all that time. Now, no more light and the car runs great. I had the same phenomenon ...


3

A misfire is detected primarily by the crankshaft sensor. It will actually detect a speed variation caused by a weak contribution from the weak cylinder. The computer knows which cylinder is misfiring by the crank location. A fault code is triggered when a misfire is detected multiple times. Many times a misfire is detected before it is noticed by the driver....


0

Fix the exhaust leak, impossible to diag properly with a leak. Then look at O2. If your car has been running rich for a long while, your catalytic converter is likely bad or going bad. I would also check for vacuum leaks, that gets the engine running rich (sucks in too much air.) Actually now that I think about it, maybe it'll run lean. Unmetered air and all ...


0

This thing has vacuum leak written all over it: 44 kPa manifold pressure at idle seems high for a naturally-aspirated engine At nearly +50% the long-term fuel-trim (LTFT) is working overtime The lambda response appears to be sluggish Lumpy idle observed You might want to review this case with a similar set of symptoms.


Top 50 recent answers are included