weird jerkyness, any suggestions/ideas?

[hungryjoseph]

it's an s13, with s14 sr20, lightweight flywheel, stage 2 clutch, 11lb driveshaftI was just driving normaly today. I merged onto the beltway, and when doing so, I put a little more than the ussual load on the pedal. The car became jerky around 2800rpms to 3000rpms then became normal. I pulled over to the enxt exit to check for any boost leaks and it seemed fine. It idles perfectly at 800rpms, give or take 10, and the tempurature was sitting perfectly at 180F. After that it kept doign it randomly after 2800 rpms. Sometimes in 4000, sometimes never. I went wot to redline in 2nd gear to end of 3rd gear to see if it would still do it. I did that 3 times, and it did two jerks in 2nd gear the first time at 4000rpms, the second pull it did no jerks, but the third pull brought another 2 jerks around 4300rpms. Flywheel problem maybe? Yesterday, when I shifted into 3rd gear, and when the clutch engaged, i heard a very quick metalic grinding, but went away after 1 second when I got onto the throttle. I don't know if this is relevent to my current problem. Spark plugs maybe? i changed them about 4000 - 5000 miles ago. NGK 10$ ones. any other suggestions would be highly appreciated....

[doridori23]

Is it a very brief stutter? It lasts about 1/2 second or less?

[IanS]

which NGK plugs do you mean, and what are they gapped too. Have you cleaned you MAFs lately?

[hungryjoseph]

Is it a very brief stutter? It lasts about 1/2 second or less?

yeah, it's around that, VERy brief.

which NGK plugs do you mean, and what are they gapped too. Have you cleaned you MAFs lately?

no idea what they're gapped at, i think .33? seemed to be fine for 4000 miles. nope, i've never cleaned the mafs actually.

the car hasn't been stuttering all night. drove it over 100 miles, no stuttering, no problems. maybe a coilpack came loose for a quick moment?

[CoupedUp]

My coil packs dont have the right screws to screw them in. : (. So im sure youre fine....although....I do have misfiring/spark blowout above 8 PSI and they HKS Heat Range 8(came in the motor) so it could one of the two...or combination.

[hungryjoseph]

my gas gauge broke on me one time, and i ran out of gas on the highway. i have a 255 walboro. you think that damaged my pump? it did it ONCE today, but it wasn't a jerk, more of a quick split second hesitation. i gassed it at 2800rpms, took it through 4500, but had the hesitation at 4000. and when i filled up the tank, i put in about 10 gallons. i turned the car on, and it acted like it had no fuel, and the motor just died. i turned it on again and put it into first, and when i went off it felt liek the car was running out of gas, but was fine after 10 seconds and drove normal. is my fuel pump damaged from running out of gas that one time?

[jaboc03]

Your problem sounds a lot like the problem I had with my car last summer. It ended up being a hairline crack in a fuel line. Try checking your fuel lines if they are original.

[IanS]

Ive heard that the walbro pumps tend to eat themselves when run dry, mine turned itself inside out, when I ran it out of gas (gauge said it was 1/4 full).

[rustest86]

im having sorta the same problem but i think mines more battery related, i just did a battery relocation and have fighting bad grounds and stuff. but its doing the same thing, quick little noises, spins over but wont start, ill be driving do the street and its like someone turned the key off for a second then back on. weird stuff..... thinking about just putting the battery back cuz i didnt have problems like this before.

[hungryjoseph]

my car's been driving fine so far... but i still have some questions. i noticed something while driving that i never noticed before. when im in any gear at any rpm, if i press the throttle to 30% or more instantly, the car will hesitate, not go, immediatly, but half a second or so later. is that normal? i never noticed it until i paid attention to it. i was also recomended to change my fuel filter, which has 6000 miles on it. whats the recomended fuel filter change? it's the 240sx filter too, not the 300zx one, which i just bought. could it be the filter?

[IanS]

the hesitation sounds like a TPS issue, check the voltage, and get yourself a 300ZX fuel filter, just to be safe.

[hungryjoseph]

the hesitation sounds like a TPS issue, check the voltage, and get yourself a 300ZX fuel filter, just to be safe.

can i use brake cleaner to clean the TP sensor? it's a plug on the throttle body, right? and can i also use brake cleaner to clean my maf? cana dirty maf cause these problems?

[IanS]

The TPS can not be cleaned that I know of, check the voltage to see if it is out of spec, as for the MAFs, use electrical parts cleaner, spray it through the inside of the sensor, then let it dry, dont start the car with it wet.

[smokey240sx]

i have somewhat the same issue lately. the vaccum hose on my FPR was rotted at the end. a simple trim and now its working better. so far........

[hungryjoseph]

i checked ALL my hoses and they are most definately fine. i also have a really slow crank, it takes 3 - 4 seconds to start the motor on a cold start. a friend told me a clogged fuel filter will cause this. is that true?

[dunneright595]

i actually ha d ahose that was dry rotted and had that problem so double check em

[hungryjoseph]

changed to 300zx fuel filter, and cleaned maf/intake. what to do now? i spotted the electrical tape on my maf sensor wire coming apart, and the bare wire showing... perhaps this is the cause of my hesitation/random stumbling?

[IanS]

Its possible, are the wires soldered or just taped? Solder and Shrink wrap FTW