shaking engine, droping idle when stopping

[leveloneae86]

Hey fellow niconauts. My 1995 240sx (ka24de) has developed a problem that im sure many of you have dealt with before.

I am a avid user of the search button, but it hasnt helped me with finding what exactly my problem is. I have found related posts but they all are to vague to answer my questions.

I concluded from searching that the possibilities that cause my car to shake and dropping idle are bad mafs, bad injectors, no spark, aiv?, vacuum leak, bad spark wires or cap, kink in a line.

now to narrow my problem: the symptoms are. the problem starts when i stop and i have to rev the engine to get the idle to idle steady again.

another thing that i notice is that when i close the hood. it starts to shake too!

any ideas, tips and suggestions on how to pinpoint my problem? ill try the power balance trick later to see if all my cylinders are firing.

thanks in advance.


Modified by leveloneae86 at 2:00 PM 8/18/2007

[dickie]

if the problem is a dead injector, you can perform a quick and easy diagnostic to see which cylinder is not firing. when the car is running, pull each of the spark plug wires in succession. if the motor runs worse with that plug removed, that cylinder is functioning properly. if the idle does not change, that cylinder is dead.

check your vacuum hoses for any leaks or disconnected fittings.

clean your mafs, or borrow a friend's and plug it in to troubleshoot.

pull your iacv and clean it out, then reset your idle.

rotor and cap are so cheap you should just go ahead and replace them anyways.

[leveloneae86]

thanks for the quick response. i will do all of those things. i just have a few question. how do you reset your idle? will the check engine light come on if i disconnect my maf or iacv? wheni purchased the car the engine light came on becaus the maf was changed to the stock one from an aftermarket intake and it was reseted with a tool thats plugged into the ecu? i dont have that tool.

[dickie]

codes is not something i am proficient with at all.

resetting your idle is as simple as unplugging your TPS sensor and turning the screw on your iacv to set to 750rpm (+/-50) after warmup.

there should be a writeup to help you in the tech pages. http://www.240sxtech.com

[Spectre_240sx]

Not that it's a common issue, but I just had the same sort of trouble. For me, it turned out to be corrosion on the injectors' connections. I took a little bit of fine grit sandpaper and wrapped it around the end of a flathead screwdriver and sanded off all of the corrosion. After that the engine was running much much better. It only takes a moment, so it's worth a look.

[dickie]

im finding out my problem is also most likely electrically-related.

you should go ahead and replace your grounds, its totally worth the few dollars it costs and the hour it takes to complete.

[leveloneae86]

yeah i just saw another thread that had the same problems and checking the ground was one of the options. im trying to get a hold of an ohm meter to see if my ground ok. if not then ill do the search button again on what solutions are out there. thanks for the input.

[Axel Grungy]

check the coolant temp sensor too, my connection there was all gummed up causing stalling problems

[leveloneae86]

will do