simonsays

ok. so i replaced the fuel filter, spark plugs, spark plug wires, o2 sensors, distributor cap and rotor, battery, egr valve, PCV valve and PCV vaccum hose, and the fuel pump. after all this, the car still bucks. what i mean when it bucks is that i take off from a stop sign, and i shift into second, and the car acts like its about to stall and then starts rumbling back and forth. this happens in every gear. i cant even go WOT cuz the car doesnt respond well. the funny thing is, it comes and goes. and another thing is that when i go to start the car up, i usually have to have the car on the on position and wait for a few minutes then start it up for the car to start up normal. if i just got in the car and tried to start without waiting it out, the car just cranks about 5 times then starts up like its about to die, then it kicks in.
i've been trying to think of what the problem would be, but its starting to irritate me real bad.
please help me with this.
i would like to hear any opinions on this situation.
thanks.
- simon

OK GUYS UPDATE TIME ON THIS SYMPTOM.
ok, i noticed this for the past few days. in the morning, when i turn the car on and drive it to work, its perfectly fine. i smash it, and it responds. but after i get off work at like 7 p.m. the car does the buckin' and the response is horrible. just thought i would throw that in there.

hemogoblin

I had the same problem after a tune up. Either a vacum hose is loose in the Throttle body, or its dirty.

simonsays

throttle body?
hhhhmmmm
i'll check up on that too.

lxsv8

Please keep us informed. I have changed air filter, plugs, leads, rotor caps, coils, injectors, fuel filter, bypassed fuel pump, tried another working ECU and still have similar problem. Mine starts bucking (surging ) when ever I take my foot off the accelerator at all speeds.

I have also cleaned Throttle body, new TPS, cleaned ICV, and started pulling all my hair out!!!

simonsays

ok. well here's the run down on my engine.
its a 5 speed. and it has roughly 210K miles on it.
i was looking under the hood yesterday and i read on one of those stickers on the hood that it requires platinum tipped spark plugs. would that have anything to do with this problem?

dejacky

iTrader: (2)

There are others here with more mechanical experience than me, but when was the last time you changed your timing belt, drive belt, timing belt tensioner, water pump, oil + oil filter?

DriftNsc3

I have Bosch Platinum 2s in my sc thats a 5 speed and has 203k miles and it still bucks,its really starting to **** me off.BTW it had bosch platinums in it when i change them so i thought getting the 2s my help some but it did nothing.
Richard

simonsays

i'm almost due for an oil change and oil filter. i change it every 3000 miles. the timing belt and dirve belt and all that, i havent replaced because i bought the car in august of 2005. the thing is, i dont want to spend all that money trying to replace the belts and pumps and end up with the same result. i guess the only thing i can do is keep driving the car like this and just wait until i get a new motor or something else happens.
the thing that really ticks me off is that this problem comes and goes. another side note is that this doesnt happen that much when i'm going down hill. when the car is under load, this starts to happen. when i try to WOT, it happens also. anybody think its maybe the fuel injectors?

DriftNsc3

Simon,it sounds like were having the problem.Where do you idle?After my last post I had to go help a friend at his house and on the way there at a red light I noticed that i was ideling at
1800rpms!!!! I have no idea why its that high.After I noticed that I started bringing my revs above 1800 before disengaging the clutch all the way when i had to shift and I actully hit the gas without it bucking,felt good,lol.

simonsays

driftnsc3
i sent u a PM

hemogoblin

Guys we all had the same problems. My idle was very high, stumbled upon accel, and even more so when stepping off the pedal.

A shop did my tuneup (yeah i got raped), I got new plugs, wires, cap, rotor, gaskets, and a high output alternator. Anyway, the problem was definelty in the throttle body/hoses area. I took it back to them a few times, and finally got it right. But they basically cut some old brittle hoses and made them tighter.

Searching will help also, I remember running across a few threads with the same problem. And yeah I know its annoying, but DONT live with it. Fix it, its simple.

This is on my 92 sc300 with 186k. Funny, this is the problem that prompted me to go for a 2JZGTE swap. It pissed me off so much, I went and started buying turbo parts, but now my car is running fine, I just got the itch for boost.

simonsays

how many hoses are there that goes to the throttle body?
and how much was it?
i did clean my throttle body about 6K miles ago.

lxsv8

I also have Platinum plugs. I have just changed the AFM as well and still bucks as soon as my foot comes off the accelerator. Some thing I noticed this morning is that for the first couple of minutes driving (before the guage goes to normal operating temp) there are no surging or bucking problems at all!

O. L. T.

iTrader: (17)

Sounds like it has a little TEXAS in it.

lxsv8

This weekend I am going to pull off the throttle body completely and make sure the gasket between it and the manifold (a paper one I think) is still intact. As now I really beleive that air is sucking in somewhere it should not be.