oung

hey guys/gals anyone with any knowledge on this issue or experience with this problem please help me out here...problem is when i drive my car wether its cold or warm i have the same issue when i completely floor the gas pedal, it pulls back and hesitates like its holding back and i can smell exhaust gases if my windows are rolled down...smells very rich.... and doesn't really accelerate at all but if i only slightly give it gas it will drive just fine....i've replaced numerous things on this vehicle but am running out of options...can anyone give me feedback to help me solve this?

things i've replaced/checked:

300zx fuel filter
distributor cap and rotor
spark plugs
spark plug wires
tps (also adjusted to right settings)
Cam Timing set to OEM specs
2.5" straight pipe from exhaust manifold to R34 skyline exhaust
checked fuel injectors all seem fine...

things i haven't changed:

MAF
Coolant temp sensor
O2 Sensor
Knock Sensor

I'm planning on replacing the coolant temp tomorrow but just wanted to see if anyone can pinpoint exactly what the issue is?? oh and also I'm ordering a new knock sensor too....

ShimiBoi

a bad maf, o2, and coolant temp would make your car run overly rich. it could also be something wrong with your ecu. im not 100% sure if these would cause your problem but for sure any one of the 3 things i mentioned above will make your car run too rich. on a seperate note, unless your car is turbo or you are running a higher pressure fuel setting/bigger injectors you dont need a 300zx fuel filter (just my ). gluck with your problem.

240mike1022

Im going thru a similar issue with my 95 it was once auto than i converted it to a 5 speed a stock ka I cbchanged my wires and plugs and it may be in my head but it does it less often since my issue doesn't occur all the time but nonetheless I felt it hesistate for like 2 secs than start accelerating.. also I feel like im at a loss of power compared to my old 93 ka hatch...and I doubt it but idk if its cuz I came from a 93 ka to a b20 swapped civic than to the 95 that I feel like im not getting the power I feel my ka has???

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Sezio

s13 KA's are much stronger than s14

Swifty

Weak fuel pump maybe had a similar problem with a buddies 240 had no power at all. After we changed the fuel pump it was good to go.

Just giving some ideas might be wrong tho.

iamtheyi

If your check engine light is not on, it's not the MAF or the Knock. I would clean the maf anyway for kicks. But yes, a lot of people, who didn't throw a code, have had problems with the fuel pump starting to go bad and replacing that. You changed all the spark stuff so I would guess it's a fuel issue.

Breaking it down, no MIL means fuel. MIL means probably a sensor and you should scan and post up your findings.

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818 ZENKI

I had this on my redtop sr...check to see if your maf connector is loose, clean your maf, clean your iacv, check for vacuum leaks, clean your throttle body, and double check your tps.

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WTB: S14 Wiper motor and S15 HLSD w/ Shafts
It's always broken!

sixtyfiveolds

im goin thru a similar issue on my '93 vert. engine was replaced recently from another s13. it would get like 28 mpg but have no power at all. running lean. then i changed the fuel filter and thing weighed like 10 pounds probably the original factory one after 140k miles haha. that plus all the fuel hose was cracked from the tank up til the filter. pressure buildup!

small fix. but it still has no balls and pings on light throttle, even when its on a cold morning right after start up. did all the plugs wires cap rotor knock sensor & maf. still trying to figure this thing out.

all i can think of is a bad coolant temp sensor for the ecu makin it rich to the ecu, but evened out with a plugged fuel filter over time lol. dirty injectors could be a result too.

Swifty

^ever changed the fuel pump?

AutechKouki

I second this. Also make sure the gaskets on the tank are all good, including hoses. Low fuel pressure causes hesitation.

RickyS13.

check the wiring for your o2 sensor as well, i have a redtop with a blacktop ecu and mine would buck at half throttle. If you depress it slightly nothing happens right? It ended up being that my wiring was wrong its like 2 or 3 wires you splice, after you replace your o2 if it still does this, unplug it and see if it still happens.

oung

ok so i had the codes run thru at pep boys and came up 4 code issues so i think my CEL isn't hooked up or the bulbs out....

Knock Sensor
IAVC
O2 heater temp sensor
and a leak from the canister from behind my rear passenger wheel...which i found out my tire rubbed the hose open so not really an issue for me...

i replaced the knock sensor but am having issues putting it back on...its really pissing me off and i already lost the knock sensor bolt somewhere and had to order a new one....question is if i have it plugged in and not attached to the block, its still going to have the issue isn't it? my assumption is that its mainly the knock sensor causing this putting my ecu into fail safe mode from what i've read

oung

i have the o2 sensor error because i did not make a new o2 sensor bung when i went straight pipe

zerodameaon

Change your EGI relays. My EGI pump relay went bad and would cause this problem. Changed it out with one from the junk yard, boom no problem.

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Need to adjust your idle?
http://zilvia.net/f/s-chassis/395413...-pictures.html

oung

well i looked under my hood and the only thing i saw that said EGI was a 7.5amp fuse and the looked like it wasn't blown so if you can guide me to where this EGI Relay is that would be great...!