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As of just a few minutes ago I popped my car into manual from a red light stop and gave it some good gas, not fully flooring it, and it gave me dramatically erratic acceleration, and by about 3000pm it gave me a flashing engine light, but no codes came up and the engine light doesn't stay on. Flashes for maybe 10 seconds and goes off. Normal speeds cause no problems. I put some acceleration on it from 2nd or third, I get the same thing; acceleration rates all over the charts with constant pedal pressure, and a blinking engine light. I've yet to dry higher RPM's or sudden RPM changes in automatic or higher gears. The most recent service of any likely relation was transmission fluid a few hundred miles back (my first of a 3x3, and it's been much smoother since then across the board). Every day my car gets some time in the sequential manual setting with a bit of spirit to it, so this didn't occur earlier in the day in the same situation. I'm not sure where to start with this, as I'm no mechanic, I just do basic maintenance. Any ideas of what's going on, and what to look into? I'll be checking this issue in automatic and other gear ranges to get a better feel for it's presentation, but otherwise I don't know where to start. It's at ~183k miles, the transmission has never given me issues. Pressure switches never changed.
Plugs were done 10,000 miles ago for reference, coils not yet any known problems so none replaced. How do I go about figuring out which specific plug or coil has gone bad, besides change one drive around and check for missfires?
IIRC turn engine on. Pull one coil at a time. Engine should stutter if the coil is good and nothing will happen if its a bad coil. I think coil 5 is usually the bad one. Pull out the spark plug and inspect it thoroughly. Also, check the ignition coil relay. The #2 15A fuse is for the relay, and the relay itself is under the dash. See if the EGR valve is clean.
Also...I find it hard to believe you had a flashing CEL and no codes. I don't have a NAV so I don't know what it can do....but will the NAV show intermittent codes or only longer term ones?
I was going to say I wasn't able to duplicate it today, having several times yesterday and today floored it through the range, in automatic and manual, with nothing. Today I floor it first to third, shift into fourth and am just coasting in a neighborhood some 10 seconds later and it starts flashing, though with no noticeable variation in speed or engine behavior.
The nav lets me look up any codes it's throwing, it just stores them there for me to look at, to my knowledge. But it may indeed not store codes that come up momentarily. I'll pull the coils one by one and see.
Well, pulled out the cords on the front three coils with it running and all caused significant issue. The back three will have to wait until I can get in there with the engine cool, just arrived home and too hot to really mess around with too easily. I'm curious if it will be immediately obvious if the problem is only coming up inconsistently as it is; it's not a constant misfire, nor even consistent in the same higher intensity situations like flooring it at any given gear/range.
So, pulled the other ignition coils and each disrupted engine flow substantially. Stopped by an Autozone on the way home just to check, and yup, P0767 (Shift solenoid valve D stuck on), P0767 (Clutch pressure control solenoid valve C stuck off). So now I'm checking through the forums here as this sounds like pressure switches but I could be recalling incorrectly. That would certainly be an acceptable minor problem. I did my recent step one of a 3x3 with redline racing ATFx2 and lightweight racing ATFx1, so it is a decent change on an overdo transmission fluid change.
Looking into the codes with more thorough explanation, both suggest one possibility is low ATF fluid. I'll be honest, I'm very much on the amateur side of auto maintenance and looking at the transmission dip stick, checking levels as described universally, some small amount of fluid goes a fair way up the stick, and I feel that the high concentration of fluid on the stick is a bit ambiguous as far as where it reaches. Meh, I'll get a few miles on it in the morning and recheck levels tomorrow and see if I want to top off, check levels, check driving symptoms and see if switches need to be ordered.
Having put some 10-15 miles of driving in this morning and checking the levels, it's definitely at least just below the minimum dot. So putting a bit more fluid in and we'll see how she acts.
To give an update for future searches on these codes and issues, I've been slowly adding more fluid to make sure I don't over due it and we're just about in appropriate ranges. With that, symptoms have continued, and today I finally got a misfire code just driving mildly up a mild hill for P0306: missifire in cylinder 6. I'm going to go swap coils 4 and 6 and see if the issue jumps to cylinder 4 so I can get that ordered and swapped and see if that has been the issue. Once that's confirmed, car is not being driven until part arrives and is swapped.
What acceptable brands have we found for ignition coils? I assume Denso will be ideal, any others worth going with to save money, or should I just stick with Denso?
What acceptable brands have we found for ignition coils? I assume Denso will be ideal, any others worth going with to save money, or should I just stick with Denso?
Do you have any bad coils? If not, why bother replacing them?
My understanding is the OEM units are made by Hitachi; the Denso units have a great reputation as well.
Do you have any bad coils? If not, why bother replacing them?
My understanding is the OEM units are made by Hitachi; the Denso units have a great reputation as well.
It would appear so, I got a P0306 today. I moved the #6 coil to cylinder 6 and reset so we'll see if it pops back up, I've been having some missfire issues as it is .Looks like transmission fluid was low and maaay have to change some pressure switches . Trying to figure it all out as an without hitting a shop.
Much appreciated. Wanted to know which we're trustable to get early in case I confirmed it was a coil. Personally that'd be my preference for outcome.
Lots of folks go to the unnecessary (IMHO) process of preemptively replacing their OEM coils and then sell the set on E-Bay/Craig's List. I'm probably going to buy a full set for something like $20 and then use them on an as needed basis (if I ever need them at all). My two J-Series engines have a combined 350,000 miles on the clock, and of the twelve OEM coils, eleven are still working perfectly.
Yup, P0304 dropped today, so looks like the coil is indeed bad. I just wish I believed this is all that was going on right now with my car/transmission, but I don't believe it is.
So, hopefully someone can help me with a question so I can avoid making a separate thread. Assuming that this ignition coil isn't the problem (it does appear faulty so is being replaced) and my transmission fluid being topped off appropriately, I will be disconnecting the battery to see if codes P0767 P0796 remain. If they do, I'm hoping for some clarification in the naming. Is the pressure control switch process related at all to the Transmission pressure control solenoid C and Transmission shift solenoid "D"? And would low transmission fluid contribute to a possibility of one being stuck on, and one off? Seems logical. I also assume these parts are probably not related to having an ignition coil gone bad or vice versa?
Anyone with experience with an Auto wanna chime in? Not sure about the auto issues and fixes. Have you searched for problems like yours? I would definitely say that the coils and trans issues have no connection. Wish I could help more. Good luck
Danke Thoi. Yeah that's the plan. Coil gets here today or tomorrow, and we'll see from there. Interestingly the car was driving better for a day when I swapped it from cylinder 6 to 4 until I tested the throttle a bit more open to check for symptom changes.
Foxnotch, yeah I've definitely looked around wherever I could find, very little info even on these codes in general, besides the code encyclopedia sites, regardless of specific car.
So I replaced the faulty coil and not only are there no misfires, the acceleration is fully responsive. It looks like the coil had been slowly going bad over a few weeks then rather quickly getting a lot worse as I opened the throttle fully (which I do frequently to varying degrees). Confusingly when I let my car sit for a few days while I was waiting for the part, the ATF dip stick showed a bit overly full if anything (only 0.1* forward tilt on the pavement where it's parked), but after driving it for a while and checking as soon as I turn off the car, there is a very thin layer of fluid that maaay go up to the first dot (unlike the thick layer that was there when it was cold). So I'm finding myself mildly confused on that front. I also noticed that when cold, the coolant is below the minimum line, when the car is used its a bit over, but needs more either way. I ordered some a few days ago to top off anyway but it won't arrive for 8 days. I didn't want to wait that long, so I grabbed a different brand which is allegedly the exact same but all these things say not to ever mix with other brands...should I wait 8 days (no one locally has the actual honda type 2 it appears...though I now realize I could probably buy some from the dealer). Thoughts?
Danke. Luckily I grabbed the alternate stuff next to my wife's work, I'll return it tomorrow and just wait the 8 days. Just hate seeing the coolant so low, but the tube was still into the liquid at it's lowest, and when it's warm it does ride much higher.
So the fun continues. Once I had replaced the ignition coil, all symptoms went away immediately. About a week later it started feeling less smooth in acceleration. A few days later...open throttle and flashing CEL. Screw it, time to take it into a shop. I discuss the matter with a couple mechanics at a local trusted shop, so they dive in and find the ignition coils are just fine, the fuel injector on the most problematic cylinder looks fine, no oil where it shouldn't be, but there are misfires on cylinders 1, 4, and 6 (Before I changed the ignition coil it started on 6..I moved to 4 and the codes followed it, and after a few days while I was waiting for a part, it's partner #1 started coding). They check the spark plug in #4 and...well...they said the filament is basically gone, they said it looked waaaay worse than the plugs they just pulled off a Kia Soul which had just had it's first change at 180k. The prong wasn't horribly out of place, so I didn't fubar the gapping, the wear was just...incredibly severe. I changed these plugs 12k miles ago. So basically at the moment the symptoms are still...weird. They say they go through about 700 cars a month and that they get one a month that is...interesting...mine gets to be that. The suggestion currently is definitely replace the plugs (trying to get the seller of my NGK plugs to replace them under warranty) and move coils 1, 4, 6 to the other three slots and see if the codes move. They said if the plug filament had fallen off my engine would be kinda fucked, so just looking at a severely faulty plug(s). They only checked the #4 plug but I'll just be replacing them all and seeing how it goes.
The prong wasn't horribly out of place, so I didn't fubar the gapping, the wear was just...incredibly severe.
The thing is, with modern plugs you SHOULD NOT need to gap them, and if you do, it is extremely easy to FUBAR them as the electrode "pads" are easily damaged.
I've checked it cold, light use, heavy days use right after 20 miles of driving, etc. The shop said levels were fine.
The NGK plugs I'd gotten weren't gapped to acura TL spec when I got them. Close, but not within range.
They should be gapped correctly from the factory. The thing is, you cannot check modern plug in the old school way by using standard feeler gauges. The best advice it buy new plugs, put them in without messing with their gap.
Thew new NGK plugs out of box are gapped to about 0.30
Well, my mechanic was not bloody kidding, every plug looked like this; the tip was entirely worn off ALL of them. I'm wondering if the seller gave me fake/used plugs. As we can see from the picture, the left is the new one, the right is the plug that I had in for 170k and the middle is the one I just took out that had about 12,000 miles.
Cut that post off before I was done but was distracted: ngk are factory gapped to about .30 instead of around .44 where they should be for our engines
After replacing the plugs my engine is immediately responsive and performing consistently well with no problems with throttle wide open . So I'm hoping this was a faulty or fraudulent batch of plugs so that we can consider this a fix, but time will tell for now. My mechanic couldn't imagine something else that could have done this so quickly.
10-10-2018, 04:21 PM
