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I’ve got a 98 civic ex 5 speed 1.6l vtec.
I’ve had the problem for a while tested and replaced a few things (some needed replacing anyways). It’s a rebuilt engine with 10k on the build. Brand new plugs, coil, wires, crank sensor, fuel rail was cleaned, new air filter, cleaned out throttle with a wire brush, and the problem still persist.
While accelerating the car jerks a little from 2k to 3k rpms and while going up a hill. The car doesn’t miss if you have it in neutral or gear and hold the rpms at any range.
A day ago I pulled the head checked the pistons and valves, head was pressure tested, reput car in time and ran a compression test. All turned out okay.
I haven’t replaced these two things however I’m not sure exactly how much of a roll these may play, I haven’t changed my fuel filter.
I also have a 12″ sub with a 750 cheater amp. My battery is newish (less than a year) however it’s fairly small is it possible that enough spark isn’t getting to the plugs under load? Just curious.
Had alternator checked and it’s good.
Any help is much appreciated.
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I see nobody has responded yet, so I’ll offer a couple basic ideas. The issue of it being under a load while acting up sounds a bit like an ignition issue, especially with reference to hills. You should check the distributor and rotor for carbon tracking, any cracks or oil that has leaked into the distributor cap. Also, even though the coil is new, test it. Sometimes they only act up after the car has warmed up a while. Last year I purchased a bad one from an auto parts store.
A couple questions:
Are there any recent check engine/ DTC codes associated with the problem?
We’re the fuel injectors cleaned when you addressed the fuel rail?
Did you go back with original OEM Honda ignition components? ( Hondas are notoriously finicky when it comes to ignition components).
Are you able to create the misfire/jerking while brake torquing the engine in gear under a load?You should go after the fuel filter to ruled that out. These are some very basic suggestions. The real mechanics on this forum can help you go deeper…
Best of luck
Thanks for the reply, no there aren’t any engine codes stored in the memory or anything. Yes the injectors were cleaned as well and yes I used genuine Honda parts I heard Hondas don’t like aftermarket parts so I stay with OEM. I tried break torquing the engine (never thought of doing that) and everything was okay. I just replaced the fuel filter and the problem remains.
And Karl I believe they were NGK if I’m remembering correctly.
After the fuel filter was replaced I took the car to Honda for a tech to do a ride along and was told he had no clue till he looked under the hood for 100 bucks (just looking not a look and fix the problem) I’m gonna go with no on that one.
It sounds liked you are knowledgeable and careful. These kinds of things can drive you nuts. I tend to approach things from a general standpoint first, then more technical. That said, I have one other thing to suggest. There may be a small vacuum leak somewhere. You’ve done a lot lof work to the engine and it’s entirely possible a hose or gasket is allowing in some unmetered air. This too can show up at a certain rpm range. Maybe you could do a smoke test. If you didn’t want to pay for one at the shop, you could do it with a cheap cigar or two. I did this once after having a smoke test performed in a shop and found some vacuum leaks that the shop tech missed. Here is a link showing Scotty Kilmer doing this. You may also want to check your fuel pressure and fuel trims. Was your crank sensor OEM as well? Keep us posted.
It is driving me crazy..I haven’t done a smoke test so I’ll try that. My top mount doesn’t seem to be working properly holding the engine down as the engine has quite a bit of lift during the break torquing but it isn’t missing like when I accelerate. Maybe it’s torquing the Axel when driving causing the car to “jerk” or “bounce” when accelerating or going up hills?
The crank sensor I’m not sure if it was OEM I got it from Autozone however the problem was there before the replacement.And brink it has a map sensor I’ve cleaned it up already. But thanks for the suggestion.
Well, that scenario would be more likely right upon takeoff/ acceleration. If it’s truly happening at a certain rpm range, and not while shifting into another gear, I’d lean away from the transmission as the source. Of course, I’ve been wrong before. Do you still have the old coil you could swap out and try? Too bad it won’t throw a DTC at you. Sounds like someone with a good scanner needs to do some diagnostics with live data. You’ll get it figured out…
It’s not the tranny mount it’s the driver side liquid one. And I noticed it goes away slowly the faster I go (rpm wise probably because of engine revelation) yes I tried the old coil and tried a friend of mines destributor entirely. And the lead mechanic for the shop I used to work for has a scanner that reads air flow and everything. Tomorrow’s my birthday so I may nudge him as a present to let me borrow it lol. Anyways I bought a used mount from a salvage yard called hilltop Honda I’m gonna try in see if it helps any one way or another I know it needs to be replaced. Hopefully I can figure it out soon.
Gee, with a problem under load I would be chasing ignition or maybe drivetrain issues rather than vacuum leak, which is typically more an idle problem. You may need a labscope diagnostic to track this one down….
Figured I would update everyone in case someone else runs into the problem. I replaced the mount and no big noticeable difference however I did notice some of my valves were lose and others were excessively tight so I did the valve lash over again and BOOM problem fixed. Thanks for the replies everyone.
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