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99 Honda civic loosing power

My 99 civic 5 speed has a weird power loss issue. Right after starting up for the first few mins while I’m driving(any speed and gear) it’ll start lagging like it isn’t getting gas or something.

Letting off the gas peddle stops it, then pressing the gas causes it again. If I go up and down on the gas peddle it goes away for a few seconds. If I’m just at idle the idle speed goes down and down untill it almost stalls then it revs up a bit and then does it again.

I would first check for leaks in a vacuum hose.
If that doesn’t help, then I think you need to look at the Mass Air Flow sensor (MAF), and
I would also suggest that you also take a look at the Idle Air Control (IAC).

Also, I have an evap code p1457, evap control system leakage (evap canister area) not sure if that has anything to with it.

Also, it does go away after running for a few mins. It comes back after the cars been off for around 30-50 mins.

A hose runs from the evap canister to the purge control solenoid on the intake manifold just downstream of the throttle body. That may be worth a close look.

Shanonia has a good line of thought here. If you have leakage in the purge system, or the purge valve is staying open, you’ll have a vacuum leak that’ll manifest as your symptoms. If the purge line is a rubber hose (it should be), try as a test pinching it off and see if the problem disappears.

I have clamped the line from the intake-just downstream of the throttle body-to the evap canister twice and both time my car seems to have a bit more power and my problem didint happen. COULD be coincidence because it is a slightly come and go problem but it is there more often than not.

Seems like that solenoid on the throttle body where the hose goes is staying open all the time. It should only open once the engine is warmed up. Clamping that hose is doing the same thing as having the solenoid shut off the connection - without the benefit of electronic controls. I don’t know how long you can operate with that hose pinched: the canister may become saturated.

It could be a bad electrical connection or an actual failed solenoid.

It isn’t a coincidence.
Actually, it’s the purge valve that’s probably sticking open rather than the solenoid that is supposed to activate it, but I basically agree with shanonia.

Well, with the hose not clamped it didn’t happen. Few hours ago

Change my statement to “sticking open intermittently”.

Changed the purge valve, right when I got on the road my power loss happened for about 3 seconds and then just stopped. Usually lasts 30-3:00 sec-mins

Are you sure the vacuum line is not cracked somewhere also.

It again happened very briefly. I’ll take it over what was happening. I looked the line over it looked ok but I will check it again when I have a minute