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thanks for the info guys...this really helps..gives me some ideason where to go for my issues. after i sea foamed my car it took away most of the idle issues...but still after i run it a little while it will hesitate alot when i put my foot on the gas the rpm drops below five hundred then kinda shoots up
 
jumping idle when stopped

my car is sarting to do the same thing now...when its cold the idle is steady, but when it warms up or a short 5 min drive, it will start to idle between 500 and 1000 rpms ONLY when im at a complete stop. Ive read this sticky and it has informed me a lot of what to look for but my question is...which one of the diagnosis should i try first for my idling problem? has anyone elses car had the same exact symptoms as mine and what, if any, fixed the problem? im just trying to limit my diagnosis time because recently its been hard to find time to work on my car. Any feedback is appreciated.
 
Ok the speed sensor on the transmission is connected to the o2 sensor after the downpipe? My car idles reallly rough but i dont have a single o2 sensor in there I have to drill/ tap the dc header and install a new one because they decided to weld over it but this thread is pretty helpful, how else do you check vacuum leaks?

I also installed a new clutch, i bleed it, but it doest work great at all, someone told me to rebleed it and take the clutch dampener off, is this a good idea? the dampener?

this was a pretty helpful thread
 
i just bought a 240 and the old owner said it needed a head gasket. because when it would get up to normal running temp it would just bog and shut off. i changed the head gasket along with both intake manifold gaskets and now when it gets to normal running temp i just shuts off like before. i hope its not a crack in the block but the car doesn't smoke anything white out the exhaust and the oil and coolant are clean. i replaced most vaccume lines wile i changed the headgasket. its a ka240de motor.
 
ohh wow im kinda happy (no offense) to see so many bogging issues in one place...hopefully it can help me resolve my issue

im guessing this weekend...ima pull the whole manifold and change the hoses, clean it, and give it new gaskets...

maybe un block my EGR :12dunno

ive canceled out MAF cuz its new, TPS, cuz its new, fuel in general , its good...so im ppretty set in believing its a manifold issue
 
Ok ladies and gents times for some updates

as i said before i and my mech did a air leak test and plugged up a line...

so last night me an him for around 2 hours decided to test censors galore

final findings

temp sensor (red tip) is good even did what nissan FSM recomends and dipped it in boiling water with thermometer...
spark plugs: have what my mech called ''blow by'' and had a white ish tip, which he stated means running lean...
injectors: proper voltage on all four and there all spraying properly...my mech even used a stethescope to hear them and were good
MAf: voltage is good aswell
grounds: good there
timing: right on the money stock setting, weve tried advancing and retarding the f**king thing but nothing + out of that
compression tested: its at Front: 190 190 190 178: rear, which isnt too bad
EGR: got the ebay steel block off and removed EGR assembly...and that actually made the car run worst to the point that i would start it and it would die after 5-10 seconds of being on...



we moved the idle control (adjuster on the rear right side of the engine...) and that did help much...

so we tried combination of TPS and idle control movement still blah
...



any way ima try to change TPS during lunchtime today...see how things go...
 
Check your fuel pressure.

the EGR Block Off Plate requires a gasket, or you will have a big vacuum leak
 
yup, and you stated all that.

Fuel Filter?

FPR?
 
yup, and you stated all that.

Fuel Filter?

FPR?

filter strainer and pump new and FPR reads 40psi...

no codes on ECU besides EGR...and thats been blocked off with new gasket

i installed the TPS my bud told me and its different now.... the car sometimes revs at 900 and it revs itself (me not touching it at all) to 1900 and then back down,,,,and then back up again...

any other possibilities?
 
Got through the Factory Service Manual section for "Hunting Idle"
 
i bought a 91 coupe that had a bad rod knock, i replaced the engine but afterwards the car ran like shit, idle was rough b/t 250-1100 rpms and smoked really bad,turns out the ecm was tuned for bigger cams and injectors, replaced ecu with a stock one and replaced the inj, with new oem ones, car ran great afterwards, so be carefull when buying cars that other people mess with...
 
21 - 40 of 126 Posts