Today while driving my car after about twenty minutes on the road the motor started to bog with anything more than i'd say 15% throttle. That was in fifth gear while traveling 60mph. I stopped the car, put it in neutral and it idles fine. I then popped the hood to check simple connections and such, and everything checked out. Mind you the car has been driving perfect up until this point, i've put damn near 300mi. on it in the past couple days alone. Anyway, so i pull back onto the road and begin to accelerate in a decent fashion, 1st pulled fine till about 5400 , appeared to be right before vtec engagement then it cut, almost feeling like the rev limit engaging. So i shifted into 2nd and proceeded to accelerate slowly then at about 3800-4000rpm it starts to cut/bog. So then i shifted into 3rd, 4th, then 5th w/under the 15%ish throttle point. In each gear (3rd-5th) w/more than the described throttle it just bogged. I got home and checked everything out again with my friend, making sure everything was snug. The fuel pressure is ok, the fuel pump turns on, the injectors sound normal. Im puzzled because the b&m fpr, rc injectors, walbro fuel pump, plugs, and plug wires all have about 4K miles on them. Like i said before it has been running perfectly up until today. Anybody have any ideas, possibly fuel filter? ecu? a bugged injector?
Also when in neutral it will rev to just under 5500 perfectly normal then it feels like the rev limit engaging and it drops to 4000. vtec is set at 5500, 8700 rev limit, on a tuned p28 w/crome.

Any input would be greatly appreciated.

 

bump

 

Chipped ECU? a buddy of mine had this problem and it was his ecu he had to get it re-chipped...

 

you might want to check your motor mounts. ive had this experience before in my friends car. one of the screws was coming out and the car would bog down when vtec hit. check the mount by the fire wall. another time when my brothers gsr was bogging before vtec kicked was when the tranny ground came off. might want to look in on that also

 

Mine was doing the same thing last time i was Autocrossing! I was thinking filter or maybe pump.

Bump for finding out whats up!

 

i replaced the fuel filter yesterday, one because thats the only thing left fuel wise that needed to be replaced. Like i said the injectors, pump, fpr, and fuel rail all have only 4K miles on them. The problem is still doing it but its a little better. It runs decent all up until vtec. Until vtec it pulls pretty close to normal but sounds a bit off, however once i reach the 5500 vtec engagement it is as if that is the new rev limit. It will not go past 5500.
I just changed the oil yesterday along with the fuel filter, so low oil pressure can be ruled out.

The two possibilities that i am thinking right now are:

1) The chip on the ecu is screwy. It is a P28 chipped and dyno tuned on crome.

2) The dizzy is messing up (not sure if it would act like this due to a bad dizzy) I havnt had time to pull of the cap to check it out.

The plugs and wires were also replaced 4K ago.

So at this point i am open to any other ideas. Im trying to get a hold of my buddy's ecu to see if mine is the coulprit, then like i said im gonna check out the dizzy.

Oh and the tranny ground is secure, and the motor mounts are all tight. IDK how a loose mount would cause the problem im experiencing but hey stranger things have happened i guess.

 

Your tank has gas in it, right? (sorry, but I have seen this before so I had to ask)

Is the air filter clean?

Is the TPS working properly?

 

yup fresh tank of BP 93 octane

Air filter is clean and tps is fully functional

 

are you running a catalytic converter? if so, could it be clogged?

 

just installed a new high flow cat last week along w/a new 2.5" cat-back

 

well putting 300 miles in a few days could affect things it could be as simple as the fuel filter or fuel pump giving away wat 2 u have done 2 the car?

 

look up, replaced the fuel filter and still happening. Its a walbro 255 and i hope that wouldnt go bad w/this many miles. I mean i put over 15K on my last one b4 i sold the car and it was still fine