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Hello guys im apprentice-mechanic and I have a problem on my first car honda civic 1998 dx manuel transmission - 156 000 KM on the car.At low rpm the car lack power up until 2000 - 2500 rpm by lack of power I mean when you press the gas it takes time to get to 2000 - 2500 rpm.At high rpm the car accelerate fines ( i think ).
Things i checked : I changed the fuel filter , I checked the timing , I change the catalyctic converter for headers , I changed fuel filter , I added fuel and engine system cleaner , I checked the throttle cable , Spark plugs are shinning brand new, I changed Air filter also . I don't wanna change every part on the car to find the problem so I need some help from expert please. Also , when i release the clutch slowly without giving too much gas , the car drops to almost 100 rpm but then it catches back and runs ( no stalling ) I also realized the lack of power when I was going up a small hill on second gear full throotle and it almost wasnt going to make it.When your rolling really slow in first gear and you give full throotle you see that it hesitates until high RPM.I sparayed some brake cleaner near the intake to see if there a was leak but i couldn't find anything. Thank you guys

 
Rep Power: 210

Have you driven another 6th gen DX, LX model other than your's?
They have pretty ball-less low end torque so, if you haven't driven another then what you're experiencing may be normal for that drivetrain.

"I change the catalyctic converter for headers"

Are you saying that you changed the exhaust manifold to headers and a cat-back (EX/SI style) catalytic converter/exhaust?

1) Do a power balance test: https://www.ericthecarguy.com/faq/so...issues?start=3
2) Do a dry and wet compression test
3) Valve lash adjustment if needed
4) Have you performed a fuel pressure test?

Any transmission clutch slippage going on?

 
Rep Power: 518

Which timing?
What was the spec? What were the test results?


Got fault codes?

 
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hello , i havent driven another one and I changed the exhaust manifold with the catalytic converter for header , the rest of the exhaust system is there, nothing modified.No clutch slippage going on.I couldnt find a "valve" to check the fuel pressure

 
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I removed the valve cover and turned the engine to top dead to see if the marks align. And there are no codes.

 
Rep Power: 210

If you do not have service records or history through previous long term owner then a valve lash adjustment is a good place to start, free (other than tools needed), and good maintenence in general. Is the timing mark on the crankshaft pulley and timing cover matching at TDC ?

If you have craiglslist or other way of finding a similar 6th gen civic DX or LX with a manual transmission used car for sale that you can test drive it may be helpful for a comparison.

 
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Hey man this is what happens with the car i think i can explain better now.
When you are releasing the clutch slowly and lets say you wanna give more gas while releasing it , the engine doesnt rev up.Even if i give full throotle right at the friction point it doesn't rev.The timing mark are matching im gonna check the valves next.

 
Rep Power: 210

That is a better expanation..thanks.
Sounds like a possible throttle cable issue.. how did you check it and did you try adjusting it?
Is the throttle body and flap clean?

 
Rep Power: 518

Best suggestion IMO.

The engine has a whopping 106 rip-snorting horsepower in it, should it cause whiplash when you accelerate? LOL

 
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i took out the air filter to see the throttle body and my friend went inside the car to press the gas pedal.Im gonna check it again

 
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I though i was going to fly in first gear man , im joking i know its not a crazy engine but i can feel the lack of power

 
Rep Power: 210

Throttle cable adjustment:


Clean the throttle body and flap too... don't need to remove throttle body. Use TB spray and a toothbrush.

 
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Alright man i'm going do to this right now , im also going to film the dashboard to show you exactly what happens ( if this doesnt fix the problem )

 
Rep Power: 210

Just have someone in a golf cart film your car because, a golf cart can outrun your car anyway...LOL.

Joking aside, unless your engine's throttle cable has way too much slack I doubt it will solve the issue. but, a good TB cleaning and proper throttle cable tension can only be a good thing.

 
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hey buddy im gonna film today and upload on youtube for you to see clearly whats going on.I adjusted the cable it didnt do much.

 
Rep Power: 518

Pics of golf cart or it didn't happen.....

 
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Im uploading the videos on youtube right now.
edit - i will upload a third one where when you give a bit of gas at low rpm the car shakes for a second like its not getting air or something

 
Rep Power: 210

What's that bright yellow/orange (amber?) light near the tach doing on? Did you forget to mention CEL's ? Scan the codes yet and if so, which codes are coming up?
Can you get the engine to rev higher than 5000 rpms in any gear or in neautral?

 
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I took off the catalytic converter for header so the second o2 is not plugged.every gear go over 5000

 
Rep Power: 210

If you have a secondary sensor to install then use a : double sparkplug defouler mod (Google it) to keep it from throwing a CEL. IMO all signs point to the normal operation of that weak powertrain. Maybe Ezone will have more input.

 
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another video

 
Rep Power: 518

Last video sounds like a misfire on a single cylinder.......

like a plug wire leaking spark out the side of the tube,

or arc trail burned into the outside of a porcelain and in the boot of the plug wire.



The check engine light has been on all this time, when was the last time you checked for NEW codes?

 
Rep Power: 210

To test:

 
Rep Power: 518

That works when a cylinder is completely dead all the time, but not when it's a load related miss. OP seems to have a miss only under a load. (snap throttle)?
Or does it stutter (miss) under all running conditions?

One might lift the plug wires one at a time, watch inside the plug tubes for arcs coming out of the side of the wires' plastic tube arcing to the metal plug tube.

 
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Like you said it does it when I snap the throttle.When the engine was running , I unplugged all the coils 1 by 1 to see if the engine sound changes and it did.If there is arc in the tube what does it mean , i have to change to plug wires ? ( spark plugs are new )

 
Rep Power: 518

The car has only one ignition coil.
What did you unplug four of?


If spark leaks out the side of the wire through the insulation/boot/tube, then yes.

 
Rep Power: 518

 
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wow man i'm gonna check this

 
Rep Power: 210

I'm going to try that on my my engine as well. The video below seems helpful as well:

 
Rep Power: 518

It's definitely necessary to know all of those tests when dealing with 20 year old Ford products LOL