Car Hesitates...

[Green&GoldGT]

I might as well join the crowd. Mine hesitates at WOT right after i shift into the next gear. I changed my intake manifold about a month ago and at the same time, replaced plugs and coil boots(one was taking a bath in coolant-rear driver's side). I just bought a fuel filter and new PCV valve, but haven't installed them yet.

One thing I noticed is when i added 2% fuel on my XCAL2 and ran it, it was fine. Now the problem seems to reoccur.

 

[TrueBlue03]

Fixed my car finally. It was a bad coil.


have you tried replacing coils?
try the fuel filter first as its cheaper...coils are around $50 a pop.

My car would only hesitate/misfire during WOT without ever throwing a check engine light or having anything out of the ordinary show up on any scanner tools.

My problem ended up being caused by 1 bad coil...along with all the corrosion/buildup on my plugs and boots.
(My car lived next to the ocean for the first 4 years of its life AND the intake manifold blew as well)
In the end it came down to going to Kragen (because of their return policy ) and buying 1 new coil and trying it out on the cylinders one by one, until i replaced the one that was faulty.

 

[Smokeurhonda]

Fixed my car finally. It was a bad coil.


have you tried replacing coils?
try the fuel filter first as its cheaper...coils are around $50 a pop.

My car would only hesitate/misfire during WOT without ever throwing a check engine light or having anything out of the ordinary show up on any scanner tools.

My problem ended up being caused by 1 bad coil...along with all the corrosion/buildup on my plugs and boots.
(My car lived next to the ocean for the first 4 years of its life AND the intake manifold blew as well)
In the end it came down to going to Kragen (because of their return policy ) and buying 1 new coil and trying it out on the cylinders one by one, until i replaced the one that was faulty.

Do you have a tuner with Diagnostic? IF so for future reference try this. I've had many coil issues because I cut and drilled my hood scoop to make functional for cooling. Knowing this when I would wash my car all kinds of water would enter the coils causing problems. The only way to get the car to throw a misfire code is to have it constantly mis. What I would do to find the cylinder is put it in 5th and floor it. It hurt my soul but after about 15 seconds a code would pop up.

 

[97GTSTANG]

Update on my car:
After replace the plugs and the wire, the car runs like new. I am acutually getting 300miles to a full tank of gas, i used to get about 250-260. One of the wires were bad, thats why it was hesitating. I bought some autolites wires from autozone, they have lifetime warranty, so if anything happens i get a new set.

 

[Javi]

I've also had this problem before. But each time it was the IAC (Idle Air Control).

 

[Hardtop68]

I got the same problem BUT ONLYwhen the tank is below half-full... I pulled into a gas station and topped-up just after hesitation without even turning off the engine... then I went off and no hesitation occurred at all... until the talk is below half-full again... Yesterday I check all plugs and coils... everything OK... Next time I will check the fuel pump...

Cheers...