Engine Stutter

[RHS13KNetics]

i have a 1990 240sx, was driving around yesterday after putting some lucas additive in it for the first time, i went into 4th gear and my shift knob started shaking like crazy, i came to a stop and when my engine is idling it stutters like put put put put put put. whereas b4 it was a constant purr. whats wrong?

[RHS13KNetics]

okayyyy well since no one cared to help me out. i am going to in turn help ones out who have the same problem. theres a good chance that if ur engine is stuttering then you are missing. hopefully its not a BHG. use process of elimination.

1 squirt water on the vacuum connections then rev the engine to look for bubbles.

2 take out spark plugs one at a time untill the engine sounds the same while pulling one out. check THAT spark plug for damages.

3 if its not the spark plug then check the fuel injection connectors. apparently 240sx came with crappy ones and they pop loose really easy. find a way to secure it back into place or get a new one


Thx forums...

[Sleepur]

I been havin the same problem man :/ its really freakin annoying.

[s13rookie]

RHS13- which one of those solved your problem?

Ive also seen people spray water onto their spark plug wires at night. If you see sparks, they need to be replaced. Silly domestic guys.

Did you check your fuel filter?

[RHS13KNetics]

for me it was the fuel injector connectors. it turns out that the ones that the OEM 240 ones are crappy and get knocked loose after a while -_-

[Z U L8R]

gj on actually trying, and you've succeeded =]
Dave

[mothon]

Next time just pull the spark plug wire instead of taking out the plug its a lot quicker way to find out if that cylinder is firing.

[69datsun510]

Originally Posted by RHS13KNetics

okayyyy well since no one cared to help me out. i am going to in turn help ones out who have the same problem. theres a good chance that if your engine is stuttering then you are missing. hopefully its not a BHG. use process of elimination.

1 squirt water on the vacuum connections then rev the engine to look for bubbles.



Thx forums...

Ever heard of the expression " suck baby, blow is only an expression"
A vacuum would only suck, and would not be able to produce bubbles. Sorry for being a smart ass, you at least tried to help the guy out. Search how to check for vacuum leaks. Some people use carb cleaner to spray around the engine compartment. If the idle goes up you have a leak. BE CAREFUL not to heat up the engine to much or get the carb spray near the exhaust manifold. PUFF no hair!!

To locate the misfire can be a hair ripping task. If you haven't done a tune up lately, start there. Get a new cap and rotor, spark plugs, fuel filter, and check for vacuum leaks.

Then if not fixed, pull each plug wire and see if motor idle changes. If no change on a cylinder, you have a bad wire or injector on that cylinder, pull the connector on the injector to check injector. Replace if bad. If it seems to still be missing go with a fuel pressure regulator then the O2 sensor. You should be getting a check engine code for the O2 sensor. You should check the throttle positioning sensor located on the throttle body. Search how to check TPS.

Well, that should get most of the common misfire problems, but there are more. Hence, why i said a hair ripping task!

Hope I helped you out and good luck