Engine shakes, vibrations, difficult to start

[rubi]

Shakes shakes shakes while driving at speed, at idle (not all the time though), especially when it's cold. And then at startup I hear knocking noises, not loud but audible, felt at first as if there was some fiber thing making contact with the shaky car body and knocking but there's nothing like that. Lately it's been difficult to tune it, i get varient rpms at idle, start up around 500 rpm, and then it jumps to 750 and it's perfect but shaky, and then after a while it jumps to 1k rpm +/- 200, which isn't the problem but it shakes sometimes and some other times it doesn't.

The oil leaks or so(but there's oil all over, so it probably doesn't burn but leaks a little)...The exhaust is creamy greyish white, and not all the time at some specific intervals, sometimes not at all.

Last night, it wouldn't start, the engine failed to start, it didn't feel like it's over choked like in the mornings now, but it just failed, as if there weren't enough gas to run it at some sufficient rpm and when it did start it was shaky, pretty shaky and then it calmed down again. what intrigued me though, was the fact that while braking or switching to neutral, the rpm fell much slower than it should be, definitely never got a feel of lossing power, had no problem accelerating and running.

I've heard that changing oil helps with the shake (and the oil definitely need a change).

I don't wanna wait till it siezes and in the same time I don't want to just get a major job done and then missing the point compeltely, but it's obvious that the engine is at least suffering low compressions.

OR maybe I still know nothing.

[theholycow]

That sounds like fuel or ignition issues. Distributor cap & rotor, wires, plugs; carburetor, fuel pump, fuel filter...

Yeah, I really narrowed it down there, I'm a real expert...

[rubi]

Yea that's just about everything related to the combustion process

I've cleaned the carb, changed the plugs and wires...How about changing the rest and see if it works??

Good to hear though

[fa22raptorf22]

Its a carburated engine just like any other. Troubleshoot it like a piece of lawn equipment.

1) check spark plugs if they are wet or not. Regap and try again.
2) check for spark & timing (could use timing light or just check plugs visually)
3) check for fuel. make sure that the plugs are getting wet or something. I would suggest ether for starting this puppy. You could disconnect the fuel line to rule that issue out. And see if it bumps over on ether.
4) compression. check this as its the other piece of the puzzle when coming to running.

Its quite possible your carb is shot and not giving enough fuel.
Bump it with ether and post back the results.

Yea that's just about everything related to the combustion process

I've cleaned the carb, changed the plugs and wires...How about changing the rest and see if it works??

Good to hear though

[rubi]

I was just at the mechanic's today, the plugs were fine, like I said I also changed the wires, but I can safely assume that the rotor and dist. cap weren't changed before, not even once, so after 15 years and 140 000 kms, I guess it'd be better to just replace'em. A tune up wouldn't hurt, a question though; do I have to change the module??

The fuel tank emptied recently, I had to go with an empty tank to get 4 liters of gas and I guess the slug and deposits are harmful, I haven't never inspected the fuel filter, not that I would want to do that myself...Anyway this morning, I felt pulsing under my seat to the fuel tank, also I had to press the pedal multiple times to spray some gas into the carb so that the car would start...

The mechanic is gonna check the fuel pump and filters this evening.

[theholycow]

I can safely assume that the rotor and dist. cap weren't changed before, not even once, so after 15 years and 140 000 kms, I guess it'd be better to just replace'em.

Whether or not that's causing your current symptoms, they definitely need to be changed.

A tune up wouldn't hurt, a question though; do I have to change the module??

Which module?

[rubi]

um, the ignition module...

[rubi]

Changed the fuel filter and things seem bright and shiny...