car jumping and stumbling very badddd, but only when hot

[nissilvat]

ok heres the problem. at normal cruising speed, like going 40 or so, the car will start jumping and shaking really bad, if i let off the gas then hit the gas again it goes away for a breif moment, then starts again. however if iam accellerating , this will not happen at all. also, this problem only occurs when the car is at normal operating temp. in the mornin when its cold and i drive to work, this doesnt happen, only when the needle hits the halfway mark on the temp gauge which is normal temp, does this occur. i just had all 4 injectors, plugs, rotor, distributor cap, and o2 sensor replaced. the compression is fine, as is the timing, all been done by my mechanic.

any suggestions would be great. sorry bout the long post!

[nissilvat]

c'mon people, this is getting to be a very annoying issue with this car, any ideas would be great

[s13drift]

yeah my car is doing the same thing some one told me to change my fuel filter i'm going to do that tomarrow you should do it if you have not already done so. hope this helps

[nissilvat]

yeah i did that, i even blew thru the old one to see if it was bad, and it was still clean, i also use a 300zx tt filer on mine

[InsanityInc]

try changing the coolant temperature sensor.

[nissilvat]

would that be the sensor on the lower radiator hose?, like at the front of the car, on the right side by the battery... car is a 89 ka-e. also, how would that make the car jump like that?

[nissilvat]

i mean the left side, if u r lokkin at the front of tha car

[nissilvat]

i dont know if u read my other post, but just curious as to how that would make the car jump and shake like that?

[nissilvat]

on this situation, has anyone else had problems similar to mine?, if it is only doin it when the car is hot could it be some kind of valve or seal thats expanding too much and blocking something??

[240sxdriverone09]

umm well jus try the coil pack (its on the driver side fender)my uncle hooked his scanner to it and was baffled for two days and told me start replace electrical parts plugs wires distro cap rotor and such then his freind mentioned the coil pack we looked at it and tested it out on the test it was fine but when it got hot that was when it was messing up.that same thing happened to me i guessed and got luckythey are like 80 bucks through a NAPA

[NateDogg]

The coolant temp sensor may be dumping fuel when the engine is cold and when the engine is warm. It's not supposed to do that when it's warm.

Does it seem to have full power and do you get at least 300 mi/tank?If no to both I'd check the resistance on the coolant temp sensor. Resistance should go down I believe to about .33 Kohms when the engine is warm. That's the spec for the DOHC, not sure about the SOHC. Cold should be much higher. Just make sure the resistance goes down when the coolant temp goes up..

[nissilvat]

ide definitely say its seems to describe the prob's ive been having. when the car gets warm and it starts kickin, it feels like iam losin lots of power, like clutch slippage, except, i just got a new clutch and flywheel, so i know its not that. also, iam new so what does the coil pack look like,

[Scott McLellan]

Call me dumb but I don't think KA24's have a coil pack. Aren't those only on distributorless engines? Anyway, the coil is part of the distributor on a KA. The coolant temp sensor and coolant temp. gauge sendor are both located on the passenger's side of the engine under the intake manifold. The bigger one is the one you would test. Resistance between the terminals should be 170-210 ohms w/ engine @ 140 degrees F. and 47-53 ohms w/ engine @ 212 degrees F. It is best to check restance w/ the engine cool, then start the engine and watch the resistance change as the engine warms. This info is all in my Chilton manual. I would reccomend you get one cause they are quite helpful. Another crazy idea that I had cause my friends car did this (95 Altima KA) was that it had a leaky valve cover and oil was getting in the distributor I guess. Seems like your mechanic would have caught it if it was that but just an idea. Also, what did your spark plugs look like that he replaced?

[s13drift]

i'm still having the same problem on my way home the rpm's jumped really bad that i had to pull off the freeway. would the check engine like come on if the coolent temp sensor was going out or bad

[240sxdriverone09]

like i said try this

i am sorry i did not mean coil pack and guess what the coil is not part of the ditro its a seprate thing thats why when you look at the pick you see a spark wire going to the fender ie the COIL

[nissilvat]

they were cheapo's, but they had little bits of black **** on em. but new bosch ones were out in and i can tell the difference.

[nissilvat]

ok well i know what that is, and that thing has been given me probs in the past too. i think iam also gonna change the plug wire on that thing too, the tip gets corroded alot even if i clean it and put electrical grease on it. btw, how much do u think that part is and whats it called exactly??

[p00t]

Your problem does sound like a coolant sensor. Check it first. The coolant sensor can effect both timing and fuel maps. Which can cause studdering and hesitation. I drew quite a masterpeice for you, i hope you like it. Use a multimeter to check the resistance between the pins on the ECU coolant temp sensor. Remember the values are in KILO OHMS. Check the warm/hot temp after driving home from work or after youve driven for at least 5 min or so. If the resistance is out of the range the sensor will need to be replaced.

The sensor runs about $26-$32 at a dealership. Remember dont just replace things blindly... otherwise your wasting $$$$

[nissilvat]

ok does the same apply for the ka24e, which, is what i got.. i said remember that, lovin....is what i got. no but seriously, will the sensor be in the same spot on my ka-e?

[p00t]

I dont have a ka-e, but the sensor should be in the same general location. follow the top radiator hose to where it connects to the intake manifold, should be there. However i dont know if it uses the same sensor, so the resistor values maybe different. I tried looking for a 89-90 FSM online in PDF format, but all i could find was a copy of those crappy ebay ones. I know 91-98 uses the same sensor, but not sure for the SOHC motor.