240sx hesitation problem :(

[osal]

i have a hesitation problem with my 95 240sx. at first i thought it was because it needed a tune up so i changed wires, spark plugs, cap and rotor, changed oil cooland flush, changed transmission fluid and differential fluid.Nothing changed. So i started to do my own research and it turns out hesitation is a common problems in 240sxs, after researching I:cleaned mafs, Checked connectorschanged fuel pumpchecked ground( added a gound kit)checked oxygen sensor by pulling out my ecm.changed fuel filter

The car idles fine so i discarded vacuum leaks, so the other possibility was that maybe my catalytic converter was clogged, so i pulled it out today only to find out that it is hollow. The problem is that when i accelerate the rpms rise fine untill they hit around the 3k mark and then the car will start to hesitate, the car can rev past 3k but acceleration is really poor so i dont even bother. the engine is a ka24de.. with pacceseter headers, apexi exhaust and injen intake... any help guys..please cuz driving my car is not enjoyable

oh btw i run the codes in my ecu even though i dont have the engine light on and i got a code 41...which is the air intake temperature sensor i believe and after doing my research some users have actually cut it and apperantly is not that important..? please help!
Modified by osal at 5:59 AM 11/21/2007

[osal]

any help guys?

[Acecool]

hoses on fpr, replace spark plugs with NGK, check injectors

[osal]

ok i ll try that...sprk plugs i have new ones on and they ngk....is there a way to test for vacuum leaks around the intake manifold...i read somewhere about spraying carb cleaner around it while engine is on...can somebody clear me up on that?...thanks guys

[Acecool]

That saucer thing at the end of the fuel rail, just replace the hoses coming off of that with silicone hoses :-) - they WILL have cracks, mine did and everything in my car is mint and kept in awesome condition.

and, check your injectors, that could also be the problem.

[osal]

i ll try that..where can i get those silicon hoses...homedepot?...or is there a website that sells silicone vacuum hoses for the 240?...thanks man for ur help

[Acecool]

eBay, 15 bucks shipped for 3 different sizes!

[osal]

ok i am gonna order that...can the o2 sensor start goin bad even thou when i did the test with the ecu it passed?

[Acecool]

Of course, but also seafoam your car, it should help it too!

[osal]

okey i guess i ll replace the o2 sensor and see how it goes...thanks man

[osal]

i seafoamed it already

[osal]

i pulled out my spark plugs and they look white...which means i am running lean...i already replaced my pump and fuel filter...could it be my fuel pressure regulator??...help guys:(

[Acecool]

Make sure you have enough oil, and check your injectors - did you check the hoses on the fpr?

[osal]

umm wat do you mean by chekin injectors..?...physically pull them out and or follow the service manual to chek for ohms

[osal]

also can a weak coil be causing this?

[osal]

well nothin changed..i adjusted timing to stock, replaced o2 sensor but nothing....oh and also i bought a used working maf for 50 bucks to see if it was my maf but nothing changed...help guys..the hesitation is really anoying but my idle is fine.....i also noticed i have exhaust leak in my muffler...i have an apexi exhaust. any other suggestions other than my fuel pump(walbro intalled)...would help alot thanks!

[osal]

i think i am gonna make a video of my problem...

well nothin changed..i adjusted timing to stock, replaced o2 sensor but nothing....oh and also i bought a used working maf for 50 bucks to see if it was my maf but nothing changed...help guys..the hesitation is really anoying but my idle is fine.....i also noticed i have exhaust leak in my muffler...i have an apexi exhaust. any other suggestions other than my fuel pump(walbro intalled)...would help alot thanks!

[BMAR240SX]

Yea take a vid it will be better to determine the problem

[leveloneae86]

hey id like to bump this thread because i dont want to make a new one and get flamed on, u have the same exact same problem i do and i dont know whats going on.

some of the other symptoms im experiencing are:

it starts bogging once engine gets hot, as in after 15 on the freeway.

its around 2800 - 3000 rpm

my exhaust starts sounding like the subaru

i smell exhaust in my car and from the engine.

i know that my cat conv is dead would that have to do with anything? you said that your cat is hollow? i heard that if you run too rich it coukd cause your cat to disenegrate (sp) maybe u had fuel in your cat?

please update on your status or someone with a solution help. thanks

[KavG]

i got the same sort of problem...

about 3 -4 weeks ago it was sooo bad i couldnt even drive the car anymore i added about 3 diff ground wires and the car started running smooth.. just had a BIT of an idle prob but i was ok with it as long as i can get around. now its starting to hesitate again but not as bad but when i gas it gets better lol and goes away for a bit then comes back... and goes away.. i know im running rich cause my rear bumper gets full of black sh*t.im thinking maybe its the o2 and the cat? cars also got 280,000km dont know what to do with it lol but having a RWD car is excellent.

[mo20duane]

Hey guys, this is an interesting problem. I have a sr20det redtop in my 95 240 with a ton of upgrades. I just upgraded from a HKS GT2540R ball bearing turbo to a T3/T4 60-1. Now with the new turbo and wastegate and pipes, I have an idle problem. It revs fine in neutral, but idles like crap and blows out alot of smoke. When i hit around 3k rpm i get sputter/ hesitation. I had the performance shop check a lot of stuff. MAF is good, idle sensor is good, honda resistor box for 1000cc injectors are good, clips on inj. are good, fluids are good. The only thing i havent checked is the o2 sensor. Plugs have been replaced 6 times or more now. If i dont get it to work with a new o2, im buying an apexi ecu and having it tuned. if that doesnt work, i need a stock ecu, injectors, clips, and maf to get to the bottom of it. once i do this, i let you know more....

[KavG]

my pops is saying its an electrical probcould be true.. i added ground wires and it was perfect after that but then like i said it started again.. not as bad though..hees saying it might be the plugs or the wires.. i changed the plugs but not the wires.. will give it a try and see...

[devil_child]

OP check the voltage at the MAf connector. Let us know what you get for the signal voltage. FYI signal voltage is a max of 5 volts maxed out. 12volts is the power.

[lumberjackj]

well. believe it or not, ive had the same kind of problem. Replaced tons of parts...even spark plug wires....turns out the spark plug wires from autozone are garbage and were broken before I had even installed them. FINALLY decided to swap the plug wires to some nice aftermarket 10.5mm units and now problem is solved!

[danielsan]

having the same kinda problem. kinda feels like im letting off the gas around 2,500-3500-rpms when im trying to accelerate. i notice my brothers 240 used to do the same thing but not as bad as mine does sometimes.

s13 have the intake runner vavle things right? how can i go about testing if they are working like they should??

i ran seafoam today not sure if it made a real difference. i have this problem along with no speedo, and dash lights.

[0wn3r]

OP check the voltage at the MAf connector. Let us know what you get for the signal voltage.

[s13bassboat]

gentlemen here's your answer. it's your tps sensor. in specific your 5v reference wire. these have a habit of having a poor connection. check your tps (throttle position sensor) for proper operation. 9 times out of 10 that's your problem. i too had that problem and chased for a month and finally found it. good luck and let me know how it goes.

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