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Just another misfire/rough idle thread...


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I added half can tò the throttle body directly, using a small size diameter tube which insert under the air hose and pour the seafoam slowly while some one keep the rpm on 1800, dont forget to unplug the MAF when seafoam, plug it back after having few miles on the car and seeing no smoke going out from muffler . Car is running perfect and codes till now!
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Update:

 

  1. I really need someone to tell me that #YNANSB is not in my future.
  2. My neighbors liked the seafoam show, but it didn't help my car.
  3. Swapping cam sensors didn't move the misfire.

I guess my next task is to pinpoint the vacuum leak that's coming from under my intake manifold.

 

Thoughts on painted intake manifolds?

Edited by StkmltS
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So I've been reading all of of the build threads on here and I'm scared that the light at the end of my tunnel may be ending with #YNANSB. I may take my car to a local speed shop this weekend and see if they have an opinion about my problem.

 

Very fortunately my wife is awesome and understands how much I like the car, unfortunately (if ynansb=true) the $ for a big project like this wouldn't be available until this winter.

 

p.s. #RememberTris

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Sorry, I have not read all the six pages of your thread, but

1. have you checked your valve clearance just in case?

2. are you consuming oil?

3. does the misfire at idle happen with a cold or hot engine? (or both)

 

 

22% leakdown is pretty high in my opinion. If your valve clearance checks out OK, then it is probably ringland, since you have checked everything else.

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1. I have not checked valve clearance... the internet hasn't taught me how to do that yet haha. Any tips or links?

2. I'm consuming less than 1qt every 1500 miles. It does not smoke while running, at low or high RPM. FWIW I've only put about 5k on the car since buying it last June.

3. The misfire happens at all temps, 100% of the time.

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mmh. I think I would park it at this point until you figure out what is really going on.

 

~2.5 quart per OCI is quite high in my opinion. My engine consumes ~0.25 quart per OCI FWIW.

Checking valve clearance is really not that bad. You need to

1. take off battery

2. take off both coil packs

3. take off the valve cover (kinna of a pain),

4. and then use a feeler gauge to measure the clearance between the cam lobes and the valve lifter, by making sure the nose of the cam lobe is pointing away from the valve lifter.

 

I just did it last week. It really is not that bad. What will take most of the time is to take out the valve cover, and then put it back with a new gasket and some permatex ultra grey sealant.

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She's parked in my garage and in a somewhat organized state of undress.

 

Let me explain my oil consumption estimate... It's barely a rough estimate, more like an educated guess.

 

 

  • About 2k mi into my ownership I added 1qt to get the level to the very top side of the acceptable range on the dipstick. I had been checking the oil at every fill up, I just didn't add any oil until then. When I bought the car the oil level was within the acceptable range, but I don't remember if it was towards the high, low, or in the middle. The previous owner said the oil had been changed the week I purchased the car.
  • At the only oil change I've done so far (OCI 4,060) the dipstick still showed the oil to be on the higher side of acceptable.
  • Since that ^ oil change (1k mi) there hasn't been a noticeable change in my oil level.

 

I just got done reading a couple other valve clearance check-a-roo threads and it sounds like it's worth a shot. Work at my job #1 is slow so I can surf online much of the day and learn about our cars, but my wrench time is severely limited by job #2 and my 3 little kids who are driving their mommy crazy because they don't get to wrestle with or even see their daddy during the week. To make it more difficult, my wife loves the wagon but she hates me spending time on/under it. This weekend is our yard sale, next weekend is Father's day, the next weekend is... it never ends. We'll be out of debt this fall so I'll have time (and $) to put into the car.

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I understand. IMHO, family first :). So you do what you can.

 

What do you mean by 'acceptable range' on the dipstick? Essentially, you want the oil level to be on the 'F' all the time. See this pic:

 

http://legacygt.com/forums/attachment.php?attachmentid=140478&stc=1&thumb=1&d=1359547698

 

I don't allow my cars to be lowered than that.

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Below the first dot is LOW (add oil NOW).

Above the second dot is FULL (stop adding).

Anywhere between dots 1 and 2 is sufficient to keep your engine healthy.

I didn't know what the third dot was for.

 

I like to keep the oil in my vehicles towards the high side (almost or right at "full).

Dipstick.png.b4ccd269eec3f3bb15339b0dbecd826f.png

Edited by StkmltS
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The third dot (or notch) where it says 'hot' refers to a full level of oil when checking at operating temps. If you check when cold, then the full oil level should be at the 'full' dot.

 

I always keep my level at 'Full'. I don't even allow in between. fyi, when it is at the low mark, you are 1 quart low.

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Never let the oil get low in these cars, always keep it at or above the full line. A little more is better then not enough.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Again, i have misfire in cylender 3 and 4.....can some tell me how to check the ignition coil? I already did but probably didnt do in right way....the rpm goes down to 600 with check engine light on when car get warm otherwise it is smooth when first turn the engin on.
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Again, i have misfire in cylender 3 and 4.....can some tell me how to check the ignition coil? I already did but probably didnt do in right way....the rpm goes down to 600 with check engine light on when car get warm otherwise it is smooth when first turn the engin on.

 

Grab a sharpie marker and after you take off each coil write down the number of the cylinder where the coil came from. Do this before you rearrange anything so that you don't get confused... it's easy to get things mixed up.

 

Take off the #1 coil, take off the #3 coil.

- Put the #1 coil where #3 was, and put the #3 coil where #1 was.

Take off the #2 coil, take off the #4 coil.

- Put the #2 coil where #4 was, and put the #4 coil where #2 was.

 

^^ doing it this way will allow you to work on one side of the engine at a time.

 

If your problem moves it was your coils. If it doesn't move then do everything I did in post #1 and/or start researching #YNANSB (you need a new short block).

Edited by StkmltS
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I didn't have much time to mess with my car this past weekend, but I managed to get my tactrix cable working enough to take a snapshot and log what the car does at idle. I didn't take the time to make sure I was logging the correct parameters, I really just wanted to see what kind of numbers would show up for cyl#2. I hadn't ran the car in about 10 days so this LV snapshot is probably worthless.

 

While I was messing with the car I noticed that my coolant is really dark, it looks very much like oil is leaking into it. Going the other way, my oil looks, feels, and smells like it should. Don't flame my scientific look/feel/smell test...

 

Could that be a head gasket leak?

 

This weekend after I fix my leaky camshaft sensor I'll drive the car around and get a couple good logs.

755472020_2015-06-20_LearningView_SS_6-20-201565948AM.jpg.733101ba13d3aa798386f2c2ee26aadb.jpg

2015-06-20_romraiderlog_20150620_154511.csv

Edited by StkmltS
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By just looking at your LV, I see that you have MAF related CEL codes. Is your MAF sensor failing? Have you tried swapping with a good working one?

Those two codes were there because a few minutes before I took this snapshot I started the car without the MAF connected... doh! I've never seen these codes under normal circumstances (MAF plugged in).

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I don't think downloading the ROM resets the ECU. So you've done 30 miles. Have you been pushing the car in those 30 miles? Just wondering if you've been through all the rpm/load ranges.

 

In any case, good thing about your LV is that your car is not knocking. Also we usually prefer the four long term fuel trims values to stay within +/-5%.

 

Those four fuel trims value may indicate the following:

-large positive values outside the above mentioned range may indicate vacuum leaks (values are positive as the ECU has detected that more air is getting in than it was measured by the MAF sensor--so it is adding fuel)

-large negative values outside the above mentioned range may indicate boost leaks (ECU detected that only a portion of the measured air by the MAF sensor actually got inside the combustion chambers--so it is pulling fuel)

 

fyi..

Edited by xt2005bonbon
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