95 240sx, idle fines but bogs when rev'ed

[AzNCmB]

Do anybody know the symptoms of a bad tps? I have a 95 240sx.

With my car, everytime MY car is running.....the idle is perfect and when I try to tap the gas a couple of times to rev it up, the car would bog!! and stumble...etc... and i would have to floor it to bring the revs up, and while the rev's are going up, the car would bog and the revs would fluctuate....and you would hear pops from the rear of the car through the exhaust.

What have I tried?, I"ve did a fuel injector addictive cleaner, fuel system addictive cleaner, changed the fuel filter, checked my timing, and cleaned my throttle body. The car's drivibility is so bad that when I let go my clutch (in every gear) it would bog and rev's would fluctuate!! and die if i dont rev the car really high. I even checked the fuel injectors by spraying some throttle body cleaner spray into the intake pipping's feeder hose that goes to the valve cover, to see if the bogging/rev flucuating would stop while spraying and reving.....but it still continued. I dont even drive the car. The car have been sitting at a small body shop and probably been moved a couple of times to in and out the shop, and I just got the car back a week ago and been dealing with this problem evere since. Before the car was brought to the shop, the car ran fine and everything.

I"ve read the ecu and it throw codes 12 (maf sensor),34 (knock sensor), and 43 (tps sensor).

I also swapped my maf with my friend's maf that has a s14 too, and it still is running bad. I dont even drive the car because I have to carefully rev the motor high or eles it would bog, rev would fall, and then die.

Through the process of elimination, I think it is a bad tps sensor. I had a check engine light for my knock sensor and that didnt effect the drivibility of the car and I've swapped my maf with my friend's maf and that didnt work.


please help anybody?

[s14xman]

go back to that shop and ask them what is up!!! But sorry to say that this is EXACTLY what happened to my old car before the head gasket blew.

[AzNCmB]

really? y did you head gasket blow? And I have already questioned the shop and the guy said the the car did that when he started it, while I was coming over there to pick it up.

any more people with any help

Thanks

[AzNCmB]

I've also changed my spark plugs, checked my rotor cap (minor corrision but not too horrible) and I"ve chagned my o2 sensor like 5 months ago. edit** i only changed the o2 sensor that is in the exhaust manifold, and i've never changed the o2 sensor that is in our 240's hollow cat, underneath the car.

would the secondary o2 sensor be a problem?

[AzNCmB]

any expert mechanics out there that can help me?

[russian]

drivibility is so bad that when I let go my clutch (in every gear) it would bog and rev's would fluctuate!! and die if i dont rev the car really high. I even checked the fuel injectors by spraying some throttle body cleaner spray into the intake pipping's feeder hose that goes to the valve cover, to see if the bogging/rev flucuating would stop while spraying and reving.....but it still continued.



i'm prety sure its your clutch, sounds like its slipping in gear. might be wrong tho :squintd:

[BuryTheNeedle]

The same thing would happen with my Corolla and it was a faulty TPS sensor. People said it could have been a vacuum leak, but after lots of money spent at shady mechanics and testing a $50 part was all it was.

Is there a lot of carbon at the end of your exhaust?

[russian]

could also be crankshaft position sensor, that will make it almost stall if its faulty.

[AzNCmB]

There is no carbon on my exhaust end.

Russian, where is the crankshaft position sensor located? Please tell me more.

Thanks

[russian]

There is no carbon on my exhaust end.

Russian, where is the crankshaft position sensor located? Please tell me more.

Thanks

right above the trany by firewall

[AzNCmB]

can you do me a favor and take a picture and post? BEcause, I've read and searched through the fsm of a 93 240sx, and it says that the crankshaft position sensor is attached along with the distributor.

I dont have an s14 fsm, but at least a 93 240sx fsm is better than nothing.

[F3600]

chekc your sparkplug... my friend plugs were not all the way in the thread. His car was doing exactly what you described
good luck

[AzNCmB]

spark plugs are fine, i've tigten them...but not too much...


LET ME TELL YOU GUYS MORE....I recently got into an accident where i ran into a pole on the driver side, the next day, i had drove the car to some body shops and it ran just as good as before the accident. The accident was around 20-25mph in my neighborhood. well, after leaving my car at the shop, i went home and my dad told me to get the car back because he knew a guy that had a body shop that would give him a good deal. so, the next day, i went and picked up the car and it still ran fine......then brought it to that shop that my dad talked about.

ok...the car sat at the shop for about a month and a half because I was finding some headlights for the car and i've bought them from a guy off of zilvia.net and he took like dam near 3 weeks to a month to send them...so after the headlights came....it took the guy like another 2 weeks to fix the car because of the wheather and he said a couuple of his guys where sick....

when i picked the car up, that's when i noticed the car ran like shiet, as i was driving home... the owner of the shop told me that it started like that when he turned the car on while i was on the way to pick it up.


anybody know what's wrong? today, i've fooled with my car, i installed a maf that i bought off of ebay and it didnt work....so i put my old maf back on.... also, the check engine light is not showing anymore...

i started sticking my head under the the car while i was reving the engine and when i got the car to bog, it seemed like cat converter that's connected to the exhaust manifold was shaking a lot and at one time it had gave off a odd smell.... and i smelt gas (rich smell) fumes while the wind blew the exhaust gases towards me...

now...do anybody know if a cat converter could do this?? or possible a o2 sensor?

thanks....

[idlafie]

Have you tried reading the Diagnostic Trouble Code off your Engine Control Unit?? Usually that will give you an idea as to what my be causing your bogging problems. Since you mentioned that you got into a front end collision with your S14, you may also want to carefully inspect the intake manifold for any leaks / cracks or damage. It's possible you could have a small vacuum leak that's causing your car to run like crap everytime you step on the gas. Check the vacuum lines running to the carbon canister along with checking the carbon cannister itself. If that doesn't solve your problems, then check to see if your ground wire on the rear driverside portion of the engine block next to the exhaust manifold/oxygen sensor is connected to the firewall as it should be.
Hope this helps...
Diego
95 S14 SE
..member...www.SoCal240SX.Org

[AzNCmB]

yeap, i read the codes about 3 days ago and it showed code number 12, 34, and 43.....12 is maf sensor, 34 is knock sensor, and 43 is tps.....but today when i cranked the engine on, it didnt show any check engine light.

Could any of you guys tell me a little more information about the crank angle sensor? In the fsm for a 93 240( i dont have the fsm for a s14 240..;() it says that the crank angle sensor is located with in the distributor rotor...Is that correct?? also, if my crank angle sensor is bad, shouldnt i get a check engine light showing a malfunction code??

Thanks

[AzNCmB]

also, my car is hard to start 90 percent of the times and I would have to play with the gas pedal(either floor it or press it half way) in order for the car to start, and when it does start, i'll have to stay on the gas for about 2 seconds or else the egine would start up and the idle would bog, fluctuate and eventually die....ANYBODY HELP...:??

Thanks

[russian]

[QUOTE=AzNCmB

it seemed like cat converter that's connected to the exhaust manifold was shaking a lot and at one time it had gave off a odd smell.... and i smelt gas (rich smell) fumes while the wind blew the exhaust gases towards me...

now...do anybody know if a cat converter could do this?? or possible a o2 sensor?

thanks....[/QUOTE]


ok 2 questions:
1) does it stall (slip) ONLY in gear or it stalls in NEUTRAL too??
if it bogs "in gear" then its your clutch. it should probably smell really nasty, like rotten eggs, or somebody who farted (if such nasty smell possible to be produced by humans)

2) if it bogs in neutral it might be your cat. try removing it and see what happens.
2)

[AzNCmB]

it bogs in gear and in nuetral...

[russian]

it bogs in gear and in nuetral...
check your cat, that might be it. did you change fuel filter?

[AzNCmB]

i've changed my fuel filter already.....

[Matt_240]

i have the exact same problem as you. id like to know how you fixed this problem. thanks!

[tchenku]

since you've already replaced the MAFS etc, try testing the MAFS for proper voltage/resistance. A friend's car had your symptoms because of a bad MAFS wire connection

I dont know the figures, but you should be able to find them online

[240 OR DIE]

Whats up Slideshow, still tryin to get that sheit worked out huh, folkin mechanics they aint no good.

[rps13 SR]

hmm u said u check the codes and said it was mafs tps and knock sensor.. the mafs change didnt fix... the knock sensor was always like that.. so the it must be ur tps man... go fix that already.. omg why ask so many questions... or go ask a mech or something if u dont know what ur doing :loco:

[AzNCmB]

sup justin.. yea the car is still fucked...
ok guys...

I've replaced my tps, the check engine lights have gone away and now i'm lost of wut to do... ;(

Can anybody help me..? The tps didnt help at all and my car have been in front my house teasing me for a month and a half now..:(..

please help...

I will try to bring it to a friend of mines to take a look at it. He works on 240's, and rx7's...

[F3600]

sup justin.. yea the car is still fucked...
ok guys...

I've replaced my tps, the check engine lights have gone away and now i'm lost of wut to do... ;(

Can anybody help me..? The tps didnt help at all and my car have been in front my house teasing me for a month and a half now..:(..

please help...

I will try to bring it to a friend of mines to take a look at it. He works on 240's, and rx7's...


do a leak down test ... maybe you have some fuc** up valve..

[rps13 SR]

do a leak down test ... maybe you have some fuc** up valve..

thats what i was gonna say next.. either that or u might have blow by.. compression test and leak down.. could be engine problem like bhg or blown rings or messed up head or something