That coil pack lasted only a couple of months . It was Duralast from AutoZone. Had the same issue again same cylinder number three . Just replaced it with a denso unit. We will see if that one holds up or if it's indicative of a different problem .
Rough Idle/Sputtering/CEL/Misfire = Coil pack problems (4 Viewers)
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That coil pack lasted only a couple of months . It was Duralast from AutoZone. Had the same issue again same cylinder number three . Just replaced it with a denso unit. We will see if that one holds up or if it's indicative of a different problem .
I had the same thing with mine this summer - ended up getting a misfire again on cylinder #5 (after chasing my tail thinking I was having a centre diff lock issue because of the code I pulled). I replaced all the spark plugs this time (200 000 miles) and the #5 coil. It was a bear to remove the rubber insulator, it got stuck down in the spark plug cavity after it separated from the coil pack. Had to buy a pair of long-long needle nose pliers to get it back out. Got about a year and a half out of this one, only a year warranty though.
John
Was on my way to the gym this morning and as I came to an idle at the traffic light... my 2002 LX started shaking pretty significantly along with a blinking check engine light. I put the truck in park and it seemed to help with the vibration... Went through the light under acceleration and the vibration ceased... Turned the truck around to head home and every time I slowed down to an idle the truck started vibrating. Also the CEL never stopped blinking. It feels like an ignition problem to me. If it is a coil pack, how do I identify which might be bad? What do yall think?
You will have to get a code reader and pull the code. It will be specific to a cylinder.
Drove it home from my folks... about a mile... blinking CEL and now VSC and VSC TRAC lights on...
Someone talk me off the ledge!
I’m also thinking about buying an ultra gauge. Will this help me identify my issue?
You should buy a code reader. I got a cheap one off amazon. The code showed three different cylinders were misfiring, so I went through them 1 by 1 until the codes went away and the engine was running good. I have heard that the sensors are very sensitive so it is common to have misfires reported in multiple cylinders even though you just need to replace a single coil pack.
266K miles on my '98 - Just started running rough last week, and engine light occasionally blinking. Bought the wifi OBD2 dongle from Amazon prime ($20 - got next day) and OBD Fusion IOS app ($10). Although 'recommended product' from amazon, took a few tries to connect. App showed 'engine light off' when it was blinking, and no codes . . . however I clicked on 'report' button in diagnostics and a report downloaded showing P0306. I swapped coil to number 1 cylinder, and got additional code (P0300). Bought the DENSO coil from local Napa store ($86) because I need vehicle - although Amazon has it for $56 and Rockauto a few $ less.
Although a cheap OBD2 scanner might be faster - the phone app is nice - it does show MPG, temp, rpm, gal/hr, MAF and more - info. It is wifi - so if used on a trip the phone cannot 'go online' because it is trying to use the OBD dongle wifi, so no OBD display + waze or Pandora/Spotify (unless I set up ipad).
Although a cheap OBD2 scanner might be faster - the phone app is nice - it does show MPG, temp, rpm, gal/hr, MAF and more - info. It is wifi - so if used on a trip the phone cannot 'go online' because it is trying to use the OBD dongle wifi, so no OBD display + waze or Pandora/Spotify (unless I set up ipad).
Same as Wolffo.
No code, no CEL, only misfiring when cold.
Replaced all spark plugs and 4 coils as they had cracks.
Still stuttering.
No code, no CEL, only misfiring when cold.
Replaced all spark plugs and 4 coils as they had cracks.
Still stuttering.
I’d suggest testing your cam and crank position sensors. On modern vehicles the ignition formula is Air, Fuel, Spark, Sensors.
Will have a look at the FSM where they are and how to it.
Is it a failure of one of them you are thinking of?
Shouldn't that cause a code?
Is it a failure of one of them you are thinking of?
Shouldn't that cause a code?
Check the cam and crank sensors and if that doesn’t work take the covers off your timing belt and check the belt. I had the same problems with mine and me and a buddy thought it was the ignition coils or CPS and come to find out my timing belt was shredded and jumped a few teeth from the cams and screwed up the timing.
Where can I find these sensors? I am searching for a drawing on the web but no luck so far.
Been thinking.
I don't really think it is the sensor. Why would it if after driving for 15 kms the misfiring is gone and the engine runs smooth again.
It must be something else, like a vacuum leak?
I don't really think it is the sensor. Why would it if after driving for 15 kms the misfiring is gone and the engine runs smooth again.
It must be something else, like a vacuum leak?
morganism
SunkCostFallacy
Try resetting the ECU? Look up the "readiness monitor drive patterns" I think ther is one in the 80 FAQ.
You can't just disconnect the neg cable, you also have to turn key to Run, and tap brakes for good measure. To clear the batt/capacitor.
I usually then restart, run it up above 1k rpm for 6-7 min till the fan comes on, then let it drop down, and hunt its own idle. This will usually get it idling well enough to get out on highway to relearn. They say it won't relearn when the CEL is on, so you may have to do this again on the apron, cuz holding down the brake at traffic lights will usually make CEL trip again...
You can't just disconnect the neg cable, you also have to turn key to Run, and tap brakes for good measure. To clear the batt/capacitor.
I usually then restart, run it up above 1k rpm for 6-7 min till the fan comes on, then let it drop down, and hunt its own idle. This will usually get it idling well enough to get out on highway to relearn. They say it won't relearn when the CEL is on, so you may have to do this again on the apron, cuz holding down the brake at traffic lights will usually make CEL trip again...
morganism
SunkCostFallacy
PS. This is a firmware flaw in an EPROM prob. Is a temp trigger in the ECU. If you get a 45f temp swing between coolant temp, and outside temp, it flips a bit, and resets ECU. So that record high may have done it. Happens peak o summer and winter her to the moms Corolla.
Filled up for the first time after replacing the fuel filter, spark plugs and 4x ignition coils.
Normally I had 18l/100km or more. Now 17l/100km.
Normally I had 18l/100km or more. Now 17l/100km.
After i installed the dual volt gauge, I noticed that the main battery is way too low when I turn the ignition key to aux.
It is showing 10.9V. :-(
An internet search shows that a bad battery can cause misfiring.
The main battery is 5.5 years old so a possibility.
I will put the battery on a charger tonight and see what happens.
It is showing 10.9V. :-(
An internet search shows that a bad battery can cause misfiring.
The main battery is 5.5 years old so a possibility.
I will put the battery on a charger tonight and see what happens.
Thank you for this post! It solved my rough running problem. I changed all 8 coils and it runs like a champ again! Mahalo
An update on my issue.
I dropped it off at my mechanic as I was sick of the problem.
He confirmed it later: one ignition coil failed.
One of the 4 I didn't change. :-(
Now everything back to normal.
I dropped it off at my mechanic as I was sick of the problem.
He confirmed it later: one ignition coil failed.
One of the 4 I didn't change. :-(
Now everything back to normal.
any thoughts given the multiple codes?
Think I just had a coil pack go out in the 100-series. Hoping that’s all but there is more than 1 cylinder misfire per the scan Advance Auto parts did for me— results below. It had been sitting for a bit over the holidays.
P0300 - multiple misfire
P0303 - cylinder 3 misfire
P0304 - cylinder 4 misfire
P0306 - cylinder 6 misfire
Cylinder 3 and 4 makes sense for a bad coil and sympathetic code in the matching cylinder (based on what I’ve read). The addition of a cylinder 6 has me concerned. It does follow 4 then 3 in firing order— not sure that means anything though.
Running rough and down on power but drivable-ish. Cleaning the MAF helped a bit.
Ordered two Denso coil packs and cable to get Techstream setup so I can dig in more.
Think I just had a coil pack go out in the 100-series. Hoping that’s all but there is more than 1 cylinder misfire per the scan Advance Auto parts did for me— results below. It had been sitting for a bit over the holidays.
P0300 - multiple misfire
P0303 - cylinder 3 misfire
P0304 - cylinder 4 misfire
P0306 - cylinder 6 misfire
Cylinder 3 and 4 makes sense for a bad coil and sympathetic code in the matching cylinder (based on what I’ve read). The addition of a cylinder 6 has me concerned. It does follow 4 then 3 in firing order— not sure that means anything though.
Running rough and down on power but drivable-ish. Cleaning the MAF helped a bit.
Ordered two Denso coil packs and cable to get Techstream setup so I can dig in more.
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