Stuttering and Stammering and Jerking and Coughing


#1

Hi,

I have a 1992 Toyota AllTrak wagon (Corola). It has about 208,000 miles on it. I live in Bend, Oregon (dry and cold and high desert-like climate). I started getting about 26 MPG, now I’m up to about 29 MPG on a consistent basis.



Ever since I bought it a year and a half ago it has stuttered and stammered. Sometimes when cold, sometimes when hot, sometimes for a long time, sometimes short, sometimes not at all. I have tried to fix it by shot-gunning the things I thought caused the problem. Right after each ‘fix’ it seemed good. Psych!!!



This is what I’ve done:

* New plugs

* New Rotor and Cap

* New Wires

* New fuel filter

* New Air filter

* New oil

* New oil filter

* New cup holder (actually it doesn’t have one, so I had to install one)

* Detailed inside and outside

* Lubed the front drivers-side brake caliper that was sticky

* Switched the studded tires for normal tires

* Replaced the broken antenna with a coat hanger (metal)

* Hmmmm…

* Now what?



The stuttering and stammering is less severe than before, but still makes itself know, on a less frequent basis, yet just as much of a stutter and stammer as when it was first noticed by this car owner.



Any suggestions? Injectors is my next guess.


#2

Do a compression test.


#3

What’s that going to tell me? I like the idea…but then what?


#4

The compression test will give you an indication of the condition of the insides of the engine. Uneven and/or low compression, signs of a worn out engine, can cause an engine to run unevenly, especially an engine like yours that was modestly powered to begin with.

I’d add to that a fuel pressure test to determine if the pump has grown weak or the regulator malfunctions, and link up with someone skilled and put the ignition on a scope. A scope will show details of how the ignition system is working. It’ll show uneven firing, low voltage (from a weak coil…you may have some shorted windings), and a myriad of other ignition related issues.

I’m guessing you have either a weak fuel pump or a weak component in the ignition system.

Yes, a sticky injector is a possibility. I’m guessing that has throttle body injection (a single injector up by the throttle body rather than an injector at every intake port???), so a stick injector could easily cause your symptoms. It can be cleaned with a parts-store solvent at little cost.


#5

i think it’s a faulty cupholder. Or coolant temperature sensor.