running rough... help!
#1
running rough... help!
So this problem has developed recently.
I have had my b16 swap with cams, valvetrain, cam gears etc with the cam gears still set a neutral.
It never did this before but recenly if I hold at a steady speed at a higher rpm it feels like my car is launching and then letting go... so it feels like I am tapping the peddle and backing off when really I am holding at a stead pace. Say 3500 rpm in 2 gear I really notice it also at 4000 rpm in 5th gear on the highway.
This only happens when I am trying to maintain a steady speed but not when I am accelerating. but sometimes on the decel.
It did it with my type r program on my p28 and its also doing it with my stock p30.
Any help would be great.
I have had my b16 swap with cams, valvetrain, cam gears etc with the cam gears still set a neutral.
It never did this before but recenly if I hold at a steady speed at a higher rpm it feels like my car is launching and then letting go... so it feels like I am tapping the peddle and backing off when really I am holding at a stead pace. Say 3500 rpm in 2 gear I really notice it also at 4000 rpm in 5th gear on the highway.
This only happens when I am trying to maintain a steady speed but not when I am accelerating. but sometimes on the decel.
It did it with my type r program on my p28 and its also doing it with my stock p30.
Any help would be great.
#3
I dont think its my clutch seeing as I have a new aftermarket clutch and flywheel just done in march... both exedy I believe.
I dont really know what else I can say...
when it happens its like I am tapping the gas really quickly and letting go but in reality my gas foot is steady. Its not as noticable as a grabbing clutch but it is noticable. It seems to be the most noticable when I am trying to maintain a steady speed at a higher rpm and happens a bit during decel too.
I dont really know what else I can say...
when it happens its like I am tapping the gas really quickly and letting go but in reality my gas foot is steady. Its not as noticable as a grabbing clutch but it is noticable. It seems to be the most noticable when I am trying to maintain a steady speed at a higher rpm and happens a bit during decel too.
#5
prolly got a bunch of lean spots....get it tuned.
Whenever you change the camshafts in an engine you NEED to tune it, not i'll tune it in a month, or run a mugen/skunk/spoon program, or the program your buddy got tuned, you need to get the partial throttle/cruise portions and WOT portions of the fuel maps tuned due to the in increased air entering/exiting your engine.
I'd also be tempted to check the TPS voltage with a multimeter, a miscalibrated TPS can cause wierd things, especially upon decel/very light throttle....if the ecu thinks the throttle is closed, it will turn the injectors off, but if the MAP sensor is still getting a vacuum reading higher than 130mbar or so then it can cause weird stuff for sure.
Whenever you change the camshafts in an engine you NEED to tune it, not i'll tune it in a month, or run a mugen/skunk/spoon program, or the program your buddy got tuned, you need to get the partial throttle/cruise portions and WOT portions of the fuel maps tuned due to the in increased air entering/exiting your engine.
I'd also be tempted to check the TPS voltage with a multimeter, a miscalibrated TPS can cause wierd things, especially upon decel/very light throttle....if the ecu thinks the throttle is closed, it will turn the injectors off, but if the MAP sensor is still getting a vacuum reading higher than 130mbar or so then it can cause weird stuff for sure.
#6
it doesn't jump in first gear.. not sure how tight the throttle cable is but I think I am going to do what andrew said. If it still does it after that at least I know its tuned properly.
I've talk to some other people who said its the fuel pump, O2 sensor.... blah blah
I cant see it being the fuel pump unless its on the way out, as for the O2 sensor..
He was saying that the fuel pump cant keep up... doesnt make sense to me.
I think it has to do with fuel delievery so I am going to try the basic things that are cheap such as changing the fuel filter and maybe adding some good injector cleaner....???
I've talk to some other people who said its the fuel pump, O2 sensor.... blah blah
I cant see it being the fuel pump unless its on the way out, as for the O2 sensor..
He was saying that the fuel pump cant keep up... doesnt make sense to me.
I think it has to do with fuel delievery so I am going to try the basic things that are cheap such as changing the fuel filter and maybe adding some good injector cleaner....???
#7
I was noticing my CAT is kind of old so I was thinking... could it be my cat is clog??? I am still running the stock SI exhaust with my engine all done.
Flowing that much through an old CAT seems to be a reasonable assumption to me????
what do you think???
Flowing that much through an old CAT seems to be a reasonable assumption to me????
what do you think???
#9
a cat issue wouldn't cause that by any means.
could be what zeeman said. your engine isnt purely stock. get a proper tune done. a "general" map layout may work for some engines and not others....
could be a vacuum issue.
could be ****ty fuel pump?(taking a stab in the dark)
a cat wouldn't cause that crazy of an issue......
could be what zeeman said. your engine isnt purely stock. get a proper tune done. a "general" map layout may work for some engines and not others....
could be a vacuum issue.
could be ****ty fuel pump?(taking a stab in the dark)
a cat wouldn't cause that crazy of an issue......
#10
^ fuel pump was suggested before as well???
How hard are they to replace on your own?
I know its through the seat... but I am not mechanically inclined by any means.
I can change my struts and springs though so you never know.
How hard are they to replace on your own?
I know its through the seat... but I am not mechanically inclined by any means.
I can change my struts and springs though so you never know.
#11
a fuel pump is pretty easy, doesn't require any special tools, just be careful not to strip the 10mm bolts that hold the top part of the gas tank (the part that holds the fuel pump) down.
Have a rag (or two) handy b/c when you pull the fuel lines off some gas will leak out (depending on how much pressure is in the lines).
Just make sure the new pump sits as low as the old pump does, b/c if it doesn't, it won't suck up the gas at the bottom of the tank, and you could be out of gas when your guage says 1/4 or 1/8 of a tank left (i've seen this before).
IMO if you are going to replace the pump, might as well do a walbro (190lph or 255lph), hell its probably cheaper as well. You can get a walbro for under $150 nowadays.
Have a rag (or two) handy b/c when you pull the fuel lines off some gas will leak out (depending on how much pressure is in the lines).
Just make sure the new pump sits as low as the old pump does, b/c if it doesn't, it won't suck up the gas at the bottom of the tank, and you could be out of gas when your guage says 1/4 or 1/8 of a tank left (i've seen this before).
IMO if you are going to replace the pump, might as well do a walbro (190lph or 255lph), hell its probably cheaper as well. You can get a walbro for under $150 nowadays.
#15
I would look into zeemans other suggestion as well, a faulty throttle position sensor causes weird things to happen sometimes, usually it would throw a code... but you never know. I still say get it tuned regardless but I don't think that's the problem since you've been running it with that program for some time now and these symptoms weren't present before.
#16
My car is now idling like a total bag of ****... I mean every time I put it in neutral it drops to almost nothing and stalls out half the time! Its not throwing any engine codes yet. Sometimes it idles just fine and next stop sign it might stall out... very inconsistant.
ANYONE??
ANYONE??
#20
^ when it comes to electronics and **** I have no clue what I am doing. I heard you take a volt meter to it but I dont know what its suppose to read and will it even start if that is un plugged? I have no clue
The reason I am trying to figure it out right now is I am kind of tight on money so I would like to do it myself it I could.
The reason I am trying to figure it out right now is I am kind of tight on money so I would like to do it myself it I could.