Problem while at freeway crusing

[teamitr]

Ok here is what is going on while crusing in the freeway and only in the freeway while going about 80mph in 5th gear at around 3000 rpm at part throtle the cars starts to buck or stumble or something like that I have tried everything boost leak etc... I even went as far as putting the stock injectors back in and taking of the afc my fuel pump is stock no aftermarkit fpr
the boost is at 12 psi. So i don't know what to do anymore. also just when that happens i look at the wideband gauge and it goes all the way to rich while it's doing that.
It will also do it when i put it in like 2nd or 3rd gear and try to do a pull from like 2000rpm
all the way to redline, but from 2000 to 4500rpm while at full throttle it will do the same thing it will buck and or stutter. until it goes above 4500 then it will run good.
Also while at the track it does not do anything from the moment i take off to the moment i cross the finish line it will run real good also while driving in the city it will run real smooth.

Hopefully someone can help me out.

 

[Defiant]

Are you trying to run BPR7 or 8?
How old are your plug wires?

 

[just2asian]

Yea, that definitely sounds like plugs or wires. I had that exact problem when I first got my car, get a fresh set of plugs and some nice wires and enjoy the stutter free rides.

 

[PieEyedPiper]

Is there a CEL accompanied with this behavior at all?

 

[teamitr]

I'm runing bpr7es's and yes i'm getting missfire in cylinder number 3, I'll try the wires since that is the only thing I have not tried. I'll keep you guys posted.

 

[Charlie90GST]

Ok, I had a problem similar to this a few months ago. Check your cv axles, I have a 1st gen fwd turbo and was having problems at hwy speeds, stumble from 3rd gear up during a race, etc. I switched out the coil, wires, plugs, everyt5hing I could think of to no effect. I gave up and took it to a mitsu dealer and found out that both of my cv axles were bad, I replaced both and haven't had a problem since.

 

[teamitr]

Ok so I changed everything plugs,wires,oil change... I even found out that my map sensor was bad so I replaced that also I tried adjusting my blow off valve and nothing. still that same problem. so any more ideas

 

[siceclipse]

my question for you is what tranny are you running that lets you do 80mph at 3000rpm?

 

[teamitr]

it's actually at around 3500. Now i was thinking that it might be the ecu but the problem is that I can be driving around the city the whole day and I can be at the track the whole day and it wont do it unless i go into the freeway and reach that rpm wich is when my boost gauge shows 0 to 3 lbs.

 

[teamitr]

Ok so I have to bring this back up because I cannot still figure it out. I just cheked the coil resistance and it was like 12.5 for both of them so i belive is withing specs.
the only thing that I'm thinking migth be doing it is the fuel filter (wich i took out and blew on it and i feelt really free) and the other thing is the fuel pressure regulator but would that cause the hesitation? Like i said before when that happens I'm at part throttle going into boost around 3000 rpm's and my wideband just goes into rich then back to fluctuating. kind off like it has the hikkups. but if i floor it from fist gear and on it will not show the symptoms at all. I hope some one can help me out since i'm trying to sale the car.

 

[PieEyedPiper]

How's your o2 sensor voltage?

 

[teamitr]

The o2 sensor is going up and down and then it reads 1volt when the hesitation occurs and then it goes back to up and down. but when it starts hesitation and i just floor it it will do it really bad and the o2 will stay at 1volt. I just did a boost leak test and it holds 20psi pretty good.

 

[teamitr]

By the way i'm using bosch wires(just exchange them at autozone) Are they really crappy to where they would be that bad when new?

 

[Smevans]

I'm having the same problem too, and rarely does it happen in the city but sometimes it does. If I turn the car off and then restart it the symptoms go away, it does come back again if I'm on the highway though.

Any chance it could be exhaust related? The reason why I ask is because I was driving on the highway one time and started having these problems with the acceleration so I pulled over and popped the hood to have a look. I noticed that one of the bolts came loose on my exhaust manifold so I tightened it up, started the car and it drove fine for a bit and then the problem came back. I pulled over again, found the bolt had come loose again so I tightened it up real tight and didn't have the problem.

Any thoughts?

 

[twicks69]

you will get a cylinder misfire, or a random misfire code usually when this happens. It should be happening between 3200-3500rpms. Most people see it happening in 5th gear on the highway. Usually if you let the car go into neutral, let the rpms return to idle (while driving still), then return into gear, the problem will go away, but the check engine light will stay on.

The key components that will be affecting this is: Crank angle sensor, Cam Angle Sensor, TPS sensor, Spark Plug Wires, Ignitor, and Coil Pack.

It is worth checking the impedence of these along with the IAC (since you are already checking the sensors).



I had this problem with my 99 GSX several years ago, and I ended up getting rid of my Magnacore wires, changed out or tested every sensor, etc.

It is also worth thoroughly checking the condition of your crank pulley for any cracking, along with checking out the timing of all the engine components. I have seen people running a crank pulley that separated, rotated 90 degrees on them, etc. and they couldn't understand why the car would run like shit.

 

[twicks69]

I'm having the same problem too, and rarely does it happen in the city but sometimes it does. If I turn the car off and then restart it the symptoms go away, it does come back again if I'm on the highway though.

Any chance it could be exhaust related? The reason why I ask is because I was driving on the highway one time and started having these problems with the acceleration so I pulled over and popped the hood to have a look. I noticed that one of the bolts came loose on my exhaust manifold so I tightened it up, started the car and it drove fine for a bit and then the problem came back. I pulled over again, found the bolt had come loose again so I tightened it up real tight and didn't have the problem.

Any thoughts?

It is NOT exhaust related.

 

[twicks69]

By the way i'm using bosch wires(just exchange them at autozone) Are they really crappy to where they would be that bad when new?

First off, visually check them out thoroughly, then measure their resistance versus the specs of "stock" ones in the mechanics manual using a multimeter.

Here is a detailed link to check your spark plug wires to see if they are all within parameters.

http://www.inct.net/~autotips/plugwire.htm


Good luck,

 

[gob4sho89]

I know this is an old thread, but I am having very similar problems. When I'm cruising on the freeway at about 3000-3200rpm, my car will studder like crazy, and my wideband will read all the way lean. It only happens on the freeway. If I cruise in any other gear at the same rpm it will not happen. Also it usually happens after I have been in the boost a little, but only sometimes. I have a 6bolt swap with 2g head....

 

[twicks69]

I know this is an old thread, but I am having very similar problems. When I'm cruising on the freeway at about 3000-3200rpm, my car will studder like crazy, and my wideband will read all the way lean. It only happens on the freeway. If I cruise in any other gear at the same rpm it will not happen. Also it usually happens after I have been in the boost a little, but only sometimes. I have a 6bolt swap with 2g head....

Check the things I have mentioned in the previous posts for fixes.