Why does my engine have low power it will not accelerate?

I have replaced the following items:
1. Camshaft position sensor.
2. Engine wire harness.
3. Upstream O2 sensor.
4. Fuel pump.
5. Injectors.
6. Coils.
7. Spark plugs and wires.
8. Misfire sensor.

I have also cleaned the Idle Air Control and the throttle body.

I am at my wits end, what else can I do?

I have a 2004 hyundai sonata 5 spd manual trans. The problem is that its arcing from where my spark plugs are located. I have replaced my spark plugs, the wires and I have used dielectric grease. I also tried it with other coils but it still keeps arcing. I have tried everything I could think of. It sparks only when I accelerate from the engine. I really don't know what to do.

Thanks for your answer. I have some auto lite double platinum spark plugs in it I gapped the at 0.044 because that's what the guys at autozone said it had to be. As I mentioned before I already tried other coils, spark plug wires, and spark plugs but it still arcs and its every time I accelerate from the engine. The engine is a DOHC 16 valve 2.4L.

It arcs from the coils but sometimes it runs thru the wires. Like I mentioned to you before I replaced wires, spark plugs and even tried other coils but kept doing the same thing. You could hear the current running thru the wires

Yeah I can see the electric discharge. My car on neutral is at 800 rpms about. When I accelerate and the rpms reach 1000 my car hits them rough. There is no lights on the dash. I took it to a mechanic to get it scanned but he said he got no codes. Also every time I turn my a/c on my car shakes heavily and drops to 500-600 rpms.

The current jumps from my coils but I already tried others but it did the same. I am going to try and regap my spark plugs. They are brand new but they just might be gaped wrong. I used an old gaping tool (worn a bit down). Thanks for your advise :)

Hi, sorry to bother you, but I am tired of the guessing games with my car. I have put a fuel pump in, checked spark plugs ( all are firing), put wholes in the catalytic converter, took the whole converter off and cleaned it out, and we have cleaned the injectors. But I still have no power when it cranks up sometimes it dies, but when you put it in reverse it will die sometimes when you put it in drive at first it might go five or ten mph for like the first ten minutes going down the road it will eventually pick up to about forty or forty five mph but hardly ever over that when you try to give it more gas it bogs down going up a hill, yeah it just does not happen at all.

Will not accelerate after warm up, it bogs and shuts off. No DTCs! Cannot attain 3,000 rpm. Crank, cam, and knock sensors, okay. New coils, plugs, wires, ballast resistor, O2 sensors, fuel and air filters.

Dsims6465

Thanks for the try, but this is not a fuel pressure problem. And the fuel pump has been changed twice with new units. When warm the car will not rev up in neutral! And the problem is somehow temp related. When cold, the car is drivable. Also, the ECU, MAF, CKP, and CMP sensors have been changed. Nothing has changed the behavior.

For the past six months I have had acceleration problems in 2001 Sonata. I had the spark plugs replaced about three months ago and all that did was stop the car from shaking like crazy. Also when I accelerate there is an ocasionally a popping sound coming from the engine. About two months ago I was driving on the Hwy and all of a sudden the car would not go over 40 km/hr and was making a noise similar sound to a bad muffler but coming from the engine. I was advised by a friend to unhook the battery to reset the computer. I left it unhooked all night and the next morning the issue seemed to be resolved but still had poor acceleration. I took it to the dealer because I didn't want this to happen again. They said the only code they where getting was a bad outout speed sensor. After they fixed this the car had no issues except for the poor acceleration still. Today driving on the hwy I had the same issue. The car would not go above 40 and there was a loud deep sound coming out of the engine that I can only decribe as sounding like a bad muffler. I don't want to have to keep replacing the sensor every couple of months as this could be very expensive. Is there anything that could be causing the sensor to keep going bad like this? The mechanic at the dealer said that replacing the sensor should fix the loss of power problem but they would need to look further to find the problem with the poor acceleration. Which of course will cost more money.

Major hesitation from 0 MPH, then takes off like a rocket; checked compression, manifold vacuum, exhaust restrictions, installed a new TPS, and now we are trying to determine what the readings should be on the MAF sensor. Should there be a 5 volt reference signal to it? This MAF is integrated with the IAT sensor (5 wire)