Well I have an 94 civic ex and it's giving me problems and the problem is that when I shift gear and go (happens on every gear) then its making this sound from the engin and plus the car is'nt picking up speed like not enough airflow going though or burning gas so I think my trans bad or clucth is bad but that's the problem I don't know well if anyone of out there know what's the problem is please.

Explain what happens a bit more closely.

Does it only happen while you're letting go off the clutch pedal? Does it stop when you let go off the clutch pedal completely? Does it happen at every RPM (same at 2000rpm and at 6000rpm)? Does it happen when upshifting as well as downshifting?

Can you determine exactly where the sounds come from? You can do like this: pull the hand brake, lift both your front wheels and drop your car on jackstands so that your front wheels are not touching the ground. Now get someone in the car and make them shift gears and pretend to drive while you open the hood and listen for sounds. Does it come from the engine, from the transmission or in between (clutch)?

Make sure you have enough oil in the engine before you do this, because if you're low on oil and lift your front end of the car too much, your engine might not be happy with the lack of oil.

Also, when you step on the gas, do the RPMs go up quickly, and car doesn't accelerate that well? What engine do you have? If it's a 1.5 liter DX, you should be at 30MPH at about 3000RPMs in 2nd gear. If you're at lower speed at such RPMs then you most likely have a slipping (worn-out, old) clutch which needs replacing. How much miles are there on your car? Has the clutch ever been replaced?

When I started the car and drive it accelerate OK but after like 2 to 3 min if the engine gets warm then the problem happens starting to not accelerate that well, it doesn't happen when I shift gear it happens after it while stepping on the gas padal. It does it at 2000rpm and like rumbles like there's something stuck inside like the intake manifold. Not picking up speed but sometimes it picks up over 3000rmp then will the after shifting gear then the same problem happens again. My engine is a 1.5 liter EX sohc Vtec the mileage's at 160,000 and I just brought the car July of this year I don't know if the clutch has been replaced yet or not

when i started the car and drive it accelerate ok but after like 2 to 3 min if the engine gets warm then the problem happens starting to not accelerate that well, it does'nt happen when i shift gear it happens after it while stepping on the gas padal. it does it at 2000rpm and like rumbles like theres something stuck inside like the intake manifold. not picking up speed but sometimes it picks up over 3000rmp then will the after shifting gear then the same problem happens again. my engine is a 1.5 liter EX sohc Vtec the mileage's at 160,000 and i just brought the car july of this year i dont know if the clutch has been replaced yet or not
So it's not about sounds, it's about performance?

My car stumbles too, and doesn't want to accelerate like it should before I reach 3000 RPMs. Did you try using any fuel system cleaner? When did you have your air filter changed? Spark plugs? Fuel filter?

Also, get your grounds cleaned. Clean your battery terminals and all ground points you can find. I'm looking into making myself a set of ground wires too.

If it means anything, my Civic '90 (1.5, 90HP) has 150.000 miles and it still has a good clutch.

And before that happened when that rpm goes high it is'nt picking up speed at all too

Because I have the same problem with my civic ex 94

and before that happened when that rpm goes high it is'nt picking up speed at all too

They are all good ideas but when was the last time the oil in your cars were changed. If your running conventional oil that's bad for a car with over 120000 miles on it. I have a 89 honda civic with the 1.5 sohc with a 5 speed trans. And my car did the same thing when I got it and I did all the same things that your both talking about and when I found out it was because the oil and the oil filter were bad and despretly needeed to be changed I was like hook me up. Anyway what I'm getting to is change your oil (if haven't yet)and if your over 150000 miles I wjhould recommend moble one fully sythetic it works wonders. I know my car is working profe