Unique misfire problem need help
#1
Unique misfire problem need help
On my recently aquired 2006 TL. It idles poorly and sometimes stalls. Under heavy acceleration there's a noticeable valve chatter around 4k. It still has excellent power under acceleration. It has a misfire in cylinder 2. It throws no codes and has none stored. I have narrowed it down to weak spark in said cylinder. I have swapped coils and still a weak spark in the cylinder. The plug looks fine, the egr ports look fine, the throttle body is clean. What would cause one cylinder to have weak spark even with known good coils plugged in??
#4
I appreciate the replies. Thank you for that. In my experience a misadjusted valve and/or low compression usually doesn't cause a low spark condition at the coil. These are definite problems that should be addressed if they were present but I'm almost positive they aren't causing the problem I'm having at the moment.
#5
Moderator
iTrader: (1)
I appreciate the replies. Thank you for that. In my experience a misadjusted valve and/or low compression usually doesn't cause a low spark condition at the coil. These are definite problems that should be addressed if they were present but I'm almost positive they aren't causing the problem I'm having at the moment.
rule it out, please.
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Acura-OC (08-24-2015)
#6
Senior Moderator
On my recently aquired 2006 TL. It idles poorly and sometimes stalls. Under heavy acceleration there's a noticeable valve chatter around 4k. It still has excellent power under acceleration. It has a misfire in cylinder 2. It throws no codes and has none stored. I have narrowed it down to weak spark in said cylinder. I have swapped coils and still a weak spark in the cylinder. The plug looks fine, the egr ports look fine, the throttle body is clean. What would cause one cylinder to have weak spark even with known good coils plugged in??
#7
Race Director
How do you know that if there are no codes?
How do you determine what defines a "weak spark"?
How many miles on the car? auto or 6MT?
Have you check the passenger side carpet for wetness?
Have you checked all plugs for proper torque?
Last edited by nfnsquared; 08-03-2015 at 02:56 PM.
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justnspace (08-03-2015)
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#9
Senior Moderator
On my recently aquired 2006 TL. It idles poorly and sometimes stalls. Under heavy acceleration there's a noticeable valve chatter around 4k. It still has excellent power under acceleration. It has a misfire in cylinder 2. It throws no codes and has none stored. I have narrowed it down to weak spark in said cylinder. I have swapped coils and still a weak spark in the cylinder. The plug looks fine, the egr ports look fine, the throttle body is clean. What would cause one cylinder to have weak spark even with known good coils plugged in??
how many miles on the car? Running premium fuel? Are you also running low on oil? Check that oil level.
#11
You're a funny man.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
#12
Race Director
You're a funny man.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
#13
Senior Moderator
You're a funny man.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
I performed a power balance test to determine which cylinder was giving me trouble. I do not need a check engine light to determine that the engine has a misfire. I will do a compression test today and report back with the results. I know there is a weak spark because I used a spark tester to measure the spark on the front 3 cylinders and the middle cylinder has a noticeably weaker spark.
I know that it's valve chatter that I am hearing because I am familiar enough with engine sounds and am not exactly inexperienced with them.
so much for "need help"
#15
Race Director
I gotta say:
1. If there's no MIL, no flashing MIL and no codes, it's not misfiring.
2. #5 is notorious for the loose spark plug issue. It's possible the chatter you heard was the fact that the plug is/was loose.
3. You also could have water in the ECM. Again, check the ECM for water stains/corrosion and also check the passenger side carpet for any signs of wetness.
1. If there's no MIL, no flashing MIL and no codes, it's not misfiring.
2. #5 is notorious for the loose spark plug issue. It's possible the chatter you heard was the fact that the plug is/was loose.
3. You also could have water in the ECM. Again, check the ECM for water stains/corrosion and also check the passenger side carpet for any signs of wetness.
#17
Drifting
Tip: Put a diaper on the ECM/PCM if it keeps wetting it self. Lol
I'm sure Pampers or Depends will work, depends on your preference or it's age I suppose. If you want a snug fit try Snuggles. Lol, puns intended.
I'm sure Pampers or Depends will work, depends on your preference or it's age I suppose. If you want a snug fit try Snuggles. Lol, puns intended.
Last edited by 01acls; 08-04-2015 at 10:51 AM.
#18
Race Director
Yeah, water in/on the ECM from the A/C drain tube getting plugged has happened several times. The water backs up in the evaporator area and then spills over and drips down onto the passenger side carpet and the ECM...
It usually results in melted/fried coil packs.
It usually results in melted/fried coil packs.
#19
Not sure how my comment gave you the impression that I thought I "know everything already". I'm also curious as to why I'm having to defend myself. I thought that the children were on vw vortex. I guess some of them decided to buy some Acuras. Anywho, the compression test was a straight 195 psi across the board. I'm going to do a leak down test this week to rule out valve issues. I appreciate all those with helpful, non-angsty teenager comments.
#20
Race Director
Well, you sure don't know which cylinder is which
#21
#22
Senior Moderator
HEY! I'm 26...
We have had our fair share of people asking questions, disregard all answers, and then "figured it out". Your posts were leading down that path. Once bitten, twice shy.
Maybe you've done most of what we've assumed you haven't done but don't actually write it out in your post thus leading us to presume you're not properly diagnosing, in which case: you know what you're doing when it comes to cars yet your writing leaves much to desire.
At the end of the day, we're trying to help you here, but you're our eyes and ears and hands. You have to help us help you too
We have had our fair share of people asking questions, disregard all answers, and then "figured it out". Your posts were leading down that path. Once bitten, twice shy.
Maybe you've done most of what we've assumed you haven't done but don't actually write it out in your post thus leading us to presume you're not properly diagnosing, in which case: you know what you're doing when it comes to cars yet your writing leaves much to desire.
At the end of the day, we're trying to help you here, but you're our eyes and ears and hands. You have to help us help you too
#23
HEY! I'm 26...
We have had our fair share of people asking questions, disregard all answers, and then "figured it out". Your posts were leading down that path. Once bitten, twice shy.
Maybe you've done most of what we've assumed you haven't done but don't actually write it out in your post thus leading us to presume you're not properly diagnosing, in which case: you know what you're doing when it comes to cars yet your writing leaves much to desire.
At the end of the day, we're trying to help you here, but you're our eyes and ears and hands. You have to help us help you too
We have had our fair share of people asking questions, disregard all answers, and then "figured it out". Your posts were leading down that path. Once bitten, twice shy.
Maybe you've done most of what we've assumed you haven't done but don't actually write it out in your post thus leading us to presume you're not properly diagnosing, in which case: you know what you're doing when it comes to cars yet your writing leaves much to desire.
At the end of the day, we're trying to help you here, but you're our eyes and ears and hands. You have to help us help you too
#24
Ok. For those who may have the same problem I had, I have solved the misfire issue. Yes, regardless of what others have said in this thread and despite their false conviction, it is possible to have a misfire without a check engine light. My timing was off by three teeth. I took the belt off, lined up the timing marks and put the belt back on. You will need a bench vice and small allen key, drill bit, or other small price of metal to press the tensioner in. The timing being off caused the misfire. I appreciate all those who tried to be helpful and at least acted their age. I might not have known what cylinder number I was talking about and may have disregarded some advice that I knew was not facing the right direction but I never acted with the childish candor that I don't even expect out of my 6 year old nephew.
#25
Race Director
Who did your TB change?
#26
I bought the car with this problem from the original owner (I'm in the car business). I am assuming, since the timing belt looks new that whoever did the service royally screwed it up. I don't know who did it but it cost me nothing to fix it thank goodness.
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