92 240sx Acceleration problem.

[Florida240sex]

I bought my car about a year ago, when i first test drove it it ran great, it was pretty peppy and put a smile on a 16 year old's face. Anyway it sat for about 6 - 8 months while i was gathering the cash for registration/insurance, once i finally had enough and got it on the road it was much slower than it was before. What's happening is that when i accelerate it kinda bogs down, when i rev it in neutral it's fine, if im driving on grass or loose dirt it also seems much better, it seems to only be a problem when it's under load. I did a burnout with it when i first got it just for S's & G's and it suprised me, so after i got it on the road and started noticing this problem i decided to rev it up and pop the clutch, and upon doing this the tires let out a quick chirp and the engine bogged down almost to a stall. Also when i first got the car i took it up to the spped limiter (115), and now i can carely get it to 100. Don't get the wrong idea im not a crazy jackass driver, i don't haul ass in heavy traffic or in mild traffic for that matter, any time i ever go fast is on a backroad with no houses or poeple that could potentialy be hurt and iv'e only done this a few times just to compare it to the way it was when i first bought it. Now iv'e already replaced the fuel filter aswell as the cts (coolant temp sensor) and it's not a clutch problem, so if anybody can give me advice on what could possibly be causing this i would really appretiate it, i want to do a ka-t build with it but not untill i solve this problem.

Sorry for the double post, but the technical forum doesn't seem very active.

[slideways...]

ummm thats a pretty vague description. thats the hard part about forum help. most people dont have a clue, and those who do fix it themselves. that said, is it running on all 4 cylinders? do you have any DTCs? just my intuition, i would look to see if all the injectors are functioning properly. then do a compression check, spark check, fuel pressure check, and timing check. let me know what you see from these tests.

[Florida240sex]

Originally Posted by slideways...

ummm thats a pretty vague description. thats the hard part about forum help. most people dont have a clue, and those who do fix it themselves. that said, is it running on all 4 cylinders? do you have any DTCs? just my intuition, i would look to see if all the injectors are functioning properly. then do a compression check, spark check, fuel pressure check, and timing check. let me know what you see from these tests.

Yes it's running on all fours, there are no problems that the dash indicates, how would you go about testing the injectors? Iv'e already done a compression check, on cylinders 2-4 i got about 175 on each but only about 165 on cylinder 1 wich makes me wonder if maybe the rings are a little worn? Also how do you go about doing a fuel pressure check? And i figured since im not getting any misfires and it's running on all cylinders my ignition would be fine, i havn't adjusted the spark timing at all so i don't see why it wouldn't be. Anyway thanks for the input!

[842skyline]

Originally Posted by Florida240sex

I bought my car about a year ago, when i first test drove it it ran great, it was pretty peppy and put a smile on a 16 year old's face. Anyway it sat for about 6 - 8 months while i was gathering the cash for registration/insurance, once i finally had enough and got it on the road it was much slower than it was before. What's happening is that when i accelerate it kinda bogs down, when i rev it in neutral it's fine, if im driving on grass or loose dirt it also seems much better, it seems to only be a problem when it's under load. I did a burnout with it when i first got it just for S's & G's and it suprised me, so after i got it on the road and started noticing this problem i decided to rev it up and pop the clutch, and upon doing this the tires let out a quick chirp and the engine bogged down almost to a stall. Also when i first got the car i took it up to the spped limiter (115), and now i can carely get it to 100. Don't get the wrong idea im not a crazy jackass driver, i don't haul ass in heavy traffic or in mild traffic for that matter, any time i ever go fast is on a backroad with no houses or poeple that could potentialy be hurt and iv'e only done this a few times just to compare it to the way it was when i first bought it. Now iv'e already replaced the fuel filter aswell as the cts (coolant temp sensor) and it's not a clutch problem, so if anybody can give me advice on what could possibly be causing this i would really appretiate it, i want to do a ka-t build with it but not untill i solve this problem.

Sorry for the double post, but the technical forum doesn't seem very active.

How does it crank over???

[Florida240sex]

Originally Posted by 842skyline

How does it crank over???

Just fine, like i said it only seems to be a problem when it's under load.

[slideways...]

if your running on all 4 cylinders, it seems like its a fuel management/engine sensor issue. if your gonna tackle this yourself i recommend at least getting a chilton manual. i dont think in 92 that the dash had a check engine light but im not 100% sure. you should be able to manually pull any codes from the CPU using a method in the previously mentioned repair manual.

[Florida240sex]

Originally Posted by slideways...

if your running on all 4 cylinders, it seems like its a fuel management/engine sensor issue. if your gonna tackle this yourself i recommend at least getting a chilton manual. i dont think in 92 that the dash had a check engine light but im not 100% sure. you should be able to manually pull any codes from the CPU using a method in the previously mentioned repair manual.

Alright thanks! Ill look into that right away!

[Florida240sex]

Originally Posted by slideways...

if your running on all 4 cylinders, it seems like its a fuel management/engine sensor issue. if your gonna tackle this yourself i recommend at least getting a chilton manual. i dont think in 92 that the dash had a check engine light but im not 100% sure. you should be able to manually pull any codes from the CPU using a method in the previously mentioned repair manual.

I did a self diagnotsic check using the ecu and it gave me code 55 (nothings wrong) Wtf!? Anybody know something else that could be causing my problems?

[slideways...]

are you sure its not a clutch problem? or a CMC problem? sorry for the swing and miss its hard to diagnose things over the net.

[Florida240sex]

Originally Posted by slideways...

are you sure its not a clutch problem? or a CMC problem? sorry for the swing and miss its hard to diagnose things over the net.

It's possible it could be the clutch i guess, it just doesn't seem like it. A while back i was adjusting my pedal to shorten the throw and several times i had it were it didn't engage all the way, so i know what it feels like when it's slipping. But i suppose if it's off by even a little bit it would definately affect the top speed and acceleration, i guess ill find out when i replace it, for now there's nothing i can do but hope that's what it is, cause at least it would be an easy fix.