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Not long ago did a engine swap because my old one had a blown gasket and this was easier and quicker to do.
Did the normal maintenance: ignition timing, spark plugs, coolant, oil, filter and some valvoline injector cleaner but for some reason when I go near the vtec point it's holding back.
Today I checked the spark plugs and 2 out of 4 are black. I know that this means the air/fuel mixture is too rich.
Engine doesn't use any oil, starts and runs great except when I hit Vtec in the beginning.
Could it be a bad rotor or a distributor or even a map sensor? Some guy at the junkyard said it could be the bearing in the distributor because I changed the timing belt but I find that hard to believe because the distributor came from my old car and that was running great before the blown gasket!
It's the same engine code and same ECU before the swap: D15Z6 all stock
New spark plugs and already dry black residue? Yes, you are correct..most likely rich fuel condition:
*Cylinder(s) misfire... do a power balance/drop test. With the engine idling remove each spark plug boot one at a time (replace before moving to next cylinder). The RPM's are supposed to drop and if not then there is a cylinder misfire. If, there is a misfire then fuel injected to the cylinder(s) is not being combusted properly causes black, dry soot to built up on plugs. Also, can eventually clog the catalytic converter.
Any dark black smoke coming from tail pipe on startups (especially cold starts)? Have someone start the engine while you check the tail pipe..look and smell for dark fumes and if it smells like fuel that's another sign of a rich running condition. Also, inspect the exhaust manifold for cracks..very common issue with 6th gens and can cause a fuel or rotten eggs smell.
Causes of cylinder misfire.. lack of: spark, fuel, air, compression, or combination of either. Start by checking spark : remove one spark plug and then reinsert plug into spark plug boot. While holding the rubber part of the boot, put spark plug electrode near chassis (ground) , crank engine and look/lsiten for spark. This is a good tester: Lisle Inline Spark Tester-LIS20610 - The Home Depot O'Reilly sells them too. If spark is good: do a dry and wet (one tablespoon of oil) compression test for each cylinder .
Vtec not engaging:
1) low oil
2) harness not connected to solenoid
3) gasket screen is fully or partially clogged causing improper oil flow.
4) solenoid is jambed/clogged and not rotating properly.
5) spool valve (top part) is faulty
6) items listed in article linked below
Remove Vtec and clean screen and valve passages with brake cleaner.
Read this for other possibilties: http://my.prostreetonline.com/2014/10/17/faq-top-ten-reasons-vtec-doesnt-work/
#9..VSS.. on that list could be the issue.The VSS is transmission specific (A/T or M/T) and were made by two different OEM manufacturers.
Last edited by Jimi Hondrix; 11-23-2016 at 09:59 PM.
To see if all cylinders are firing, disconnect the fuel injectors one at a time, not the spark plugs. The coil is prone to blow when fired into an open circuit.
Swap the fuel injectors between the bad cylinders and the good ones, drive for a little while then check plugs again to see if the problem moved.
To see if all cylinders are firing, disconnect the fuel injectors one at a time, not the spark plugs. The coil is prone to blow when fired into an open circuit.
Swap the fuel injectors between the bad cylinders and the good ones, drive for a little while then check plugs again to see if the problem moved.
Good suggestion.
For the record I've never experienced coil damage testing spark the way I stated but, not saying it can't happen either.
Yesterday I checked for misfire by unplugging the plugs 1 by 1 and idle dropped so that is all good then right?
weird thing is that first and second gear there is no weird holding back when I floor it only in 3rd gear you can feel the hiccup for a short moment and then it'a normal (still don't feel good like my old engine, also plugs shows that something is wrong)
You can also feel the hiccup when I'm near 3500rpm and floor it! Vtec is around 3500 and it isn't really that Smooth like my old engine..
Didn't check the other things because of work so Gonna check that on Tuesday.
Also here are Some photo's of the plugs and distributor
Yesterday I checked for misfire by unplugging the plugs 1 by 1 and idle dropped so that is all good then right?weird thing is that first and second gear there is no weird holding back when I floor it only in 3rd gear you can feel the hiccup for a short moment and then it'a normal (still don't feel good like my old engine, also plugs shows that something is wrong)You can also feel the hiccup when I'm near 3500rpm and floor it! Vtec is around 3500 and it isn't really that Smooth like my old engine..Didn't check the other things because of work so Gonna check that on Tuesday.
The plugs don't look too bad as the center elctrode's tip and ground electrode are not covered with dry, black soot... only the seat is.
When you performed the power balance (drop) test did they all the cylinders drop in idle close to the same amount of each other?
Is an automatic or manual transmission?
Vtec engages around 5,500 rpms not 3,500rpms. Might be a transmission isuue you're experiencing rather than an engine issue.
You never said whether your car is manual or automatic.
Check the plugs again. If the same two are still getting black, swap around the fuel injectors and test drive again. You could have someone follow you and watch if the car ever makes any smoke, if so when and what color.
Did anyone want to tell them that those are carbon deposits on the plugs? I didn't see any of that mentioned. Is the timing correct? Has it been checked? Are the spark plugs the correct plugs for the car? Correct heat range?
If all that checks out to be correct, then get yourself some BG Products 44k fuel cleaner. Dump it in the tank, then fill up. It will clean out carbon deposits in the combustion chamber. No need to keep throwing parts at it, just a waste of money.
Timing was off when swapped, did check the timing and set it to the mark but no big result 😑.
Gonna check the plugs later today..
Also already used valvoline injector cleaner, did help a bit (could be placebo effect) and we only got here Wynn's, Forte and Valvoline for cleaners. 😢
Timing was off when swapped, did check the timing and set it to the mark but no big result 😑.
Gonna check the plugs later today..
Also already used valvoline injector cleaner, did help a bit (could be placebo effect) and we only got here Wynn's, Forte and Valvoline for cleaners. 😢
Ok so timing was off and corrected.. check.. see what plugs (part number) they are, and compare it to what the manual says (or the sticker under the hood). And I think in the picture those are NGK's.. I like that brand, but the part number (heat range) is important.
Yeah I tried all the other fuel system cleaners and never really saw much if an improvement until the 44k fuel cleaner. You can order it online at amazon if you can't find it locally. https://www.bgprod.com/find-a-shop/ is where you can find shops that sell it. some will sell it to the public others say they'll only use it in a service they'd sell you. I usually call around to see if new places will sell it. It's about $20 a can. But like I was saying, it's the only stuff I've used that really worked.
The other thing to check are the spark plug wires. I didn't see anything about it, but did you get a multimeter, set it to ohms (usually the 20k setting or 200k) and put one probe to one side of the spark plug wire and the other probe touching the other side of the plug wire, checking the reading you get? If not, get a multimeter and check the wires.
Pull Vtec and clean it inside and the screen with brake cleaner..an hour long job at most. Will most likely need to use RTV or Hondabond on gasket's rubber part only as the Vtec solenoid has a tendancy to warp. Try it without the sealant first and use proper torque spec.. but, if it still leaks oil will need sealant.
You have two cylinders making soot and two not, you need to find out what is different about those two cylinders. Trying to "remove the carbon" with some miracle in a bottle is pointless as it's just going to soot up again.
You have two cylinders making soot and two not, you need to find out what is different about those two cylinders. Trying to "remove the carbon" with some miracle in a bottle is pointless as it's just going to soot up again.
According to the pics he posted the soot isn't on electrode tip and ground tip...it's only on the plug's seat but, it's still concerning for plugs that were changed recently. OP: scrape that soot off and run them again for a few days, pull and inspect for same soot pattern. At what mileage was the last valve lash adjustment performed?
Be a good idea to do a dry and wet compression test on all cylinders.
Last edited by Jimi Hondrix; 11-27-2016 at 03:04 PM.
Pulled the spark plugs out and swapped them for some others that I had laying around (all nice brownish color). Checked them the next morning and only 2 had some black soot on the seat not the center part.
Switched the MAP sensor but no results
Got another VTEC solenoid and tested it by hooking it up on 12v to see if it clicked (worked), cleaned it and replaced mine with this one!
Got some other spark wires (not new ones) and switched this with the other wires.
Also checked ECU for codes, jumped service connector but engine light was solid so either no codes or bad ECU..
At the moment got the plugs that I had laying around in it with the "new" VTEC solenoid and the other spark wires.
Did a small test drive and there is some improvement but not that much
You can feel the hiccup in 3rd! 4th not so much and when I floor it from 1st gear to 4th gear I don't notice the hiccup (maybe it's still there and I just want it that it's not there LOL )
Everytime @ VTEC point: 3500rpm
Rotor and cap are okay in the pictures or needed replacement?
Also pulled the cap off today to see if there was some play in the rotor itself but it's solid as a rock! Only the spring thingy was for some reason bend (upper part) so bend it back in the right way so it was straight again (don't know if this makes any sense )
Don't know the history of this engine... when swapped I did put on a new Timing belt with tensioner to be safe but don't know when the valves were adjusted.
D15Z6 has VTEC Switchover : depending on load, max ~3,500 rpm in 5th gear
I'm sorry, you can inspect and replace parts all over the place but you can't do a compression test?
All you need is a friend and a compression tester which will cost you less than many of the parts you throw at the car.
Agree. A compression test is definitely in order OP and throwing parts an issue without testing first is never a good idea..Performing a dry/wet compression test seems intimidating but, is actually very simple on an inline four cylinder. There's plenty of videos to show you how and Harbor Freight sells a $25 8-piece tester that is good enough for occassional use. A few tips to ( in addition to video below) during a compression test:
1) Perform while battery is fully charged to ensure starter cranks optimally.
2) Perform when engine is warm or at operating temp
3) Remove all four spark plugs (shown in video)
4) Perfrom at WOT (wide open throttle/shown in video)
5) Disconnect the distributor harness (shown in video)
6) Use a bit of oil each time/cylinder on compression gauge lead that screws into spark plug hole to prevent the lead from getting stuck
7) Don't overtighten compression gauge lead into spark plug hole.
8) If you use purchase a HF gauge use two channel locks to tighten correct adapter size onto gauge lead. If the adapter is not firmly tightened it's very possible that the adapter will satyed screwed into the spark plug hole while the gauge lead/hose unscrews and pulls out.
9) Unlike ETCG;s suggestion (in video) to crank over engine a certain amount of times per test.. another (IMO better) way is to watch the compression gauge needle rise as high as possible/peak psi and then allow for a few more revolutions past that before turning engine off.
10) Wet test oil amount = 1 tablespoon. Adding too much oil can artificially inflate compression numbers by displacing too much cylinder volume and possibly cause hydrolock. Don't be alarmed of smoke from exhaust after adding oil to cylinder .. it will burn off shortly
Once you gain confidence from doing a successful compression test use it towards a valve adjustment.. your engine will thank you and will be another area of maintanance you will have notched.
9) Unlike ETCG;s suggestion (in video) to crank over engine a certain amount of times per test.. another (IMO better) way is to watch the compression gauge needle rise as high as possible/peak psi and then allow for a few more revolutions past that before turning engine off.
The purpose of ETCG's method (I tend to do 4 or 5 cranks) is that even a weak cylinder can eventually push up to an acceptable max pressure.
Doing a set crank amount closer emulates the running engine pressure IMO. Granted the running engine piston is moving much faster, but it only compresses in one stroke. A leaky piston will leak more on the higher speed (pressure) single pass than a non leaky.
When you only crank each cylinder 3-5 times (choose a number and stick to that for each cylinder) you will be much more likely to see a weak cylinder than if you crank it until it can't create any more pressure.
Also, I've noticed 4 or 5 cranks per cylinder tends to get me results that align with the factory service manual, where max pressure is beyond that in most cases.
Both methods work, I just think the 4-5 crank method provides slightly more accurate results.
The purpose of ETCG's method (I tend to do 4 or 5 cranks) is that even a weak cylinder can eventually push up to an acceptable max pressure.
Doing a set crank amount closer emulates the running engine pressure IMO. Granted the running engine piston is moving much faster, but it only compresses in one stroke. A leaky piston will leak more on the higher speed (pressure) single pass than a non leaky. When you only crank each cylinder 3-5 times (choose a number and stick to that for each cylinder) you will be much more likely to see a weak cylinder than if you crank it until it can't create any more pressure. Also, I've noticed 4 or 5 cranks per cylinder tends to get me results that align with the factory service manual, where max pressure is beyond that in most cases. Both methods work, I just think the 4-5 crank method provides slightly more accurate results.
I used to do it the way you described. I often post ETCG's compression test video on the Civic Forums site and a long time member (15yr Honda dealer mechanic) there said he feels that ETCG's video is very good but suggested for me to try it the way I described here. My assumptions is/was that the peak compression from each cylinder, even an out of spec cylinder (10% or higher) is optimal for a compression test. Most of the compression test videos I've watch do recommend a set number of cranks per cylinder and use the same number for each cylinder. Some say 3-5, 5-8 and some are in between those numbers. I would say (in my experiences) that in most cases max psi is generally reached around 5 cranks per cylinder.
What I have experienced is using longer cranking time drains the battery enough to effect cranking by the time the 3rd or 4th cylinder is reached and that can effect compression as well. It's probably good practice to charge the battery for 30 minutes or so between dry and wet testing for optimal cranking and to give the starter a chance to cool down a bit. I will bring it up to him and see what he says. Either way a cylinder that is significantly low on compression or out of spec with the others will reveal itself.
Last edited by Jimi Hondrix; 12-02-2016 at 05:09 PM.
Okay. I posted on CF and got his reply for clarification:
(copied and pasted): " That's why I watch the gauge while I'm doing the checks, note how much the needle climbs with each 'puff'.
But really, the statement quoted (" even a weak cylinder can eventually push up to an acceptable max pressure.") .... depends on the failure...most of the time it won't be that way, but once in a while it may.
But LOW is still LOW no matter what. If one is really low, it's still gonna be low using either method.
And.....I've successfully diagnosed problems using my method that others could not when using the other method. (In one case, I was just standing nearby and watching their gauge during their testing, I could tell 2 cylinders out of 6 had a problem....but the person doing the test couldn't see it).
Same could be said for leakdown testing: low pressure vs. high pressure, each method has advantages and disadvantages."
Last edited by Jimi Hondrix; 12-02-2016 at 08:14 PM.
11-22-2016, 10:33 AM
D15Z6 - Dry black gunk on spark plugs
re: D15Z6 - Dry black gunk on spark plugs
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