Bad Valve

[59VWSC]

How would I know if I have a bad valve. Currently, my Single Cab runs terrible, has no low end power, bogs down at low rpm. Eventually, if I feather the gas pedal I will take off. Gets a little better when totally warm, but still not right.  Felt like a fuel problem, so I replaced the cheapest items, fuel filter and fuel pump. Made no difference. Motor's are not my strength for repairs. If it is a valve, is it better to buy a rebuilt long block? Please advise.

[Veeboy]

Do a compression check to see if you have low compression on only one cylinder.  Check plugs to see if you were running lean and check you valve clearance to see if any are running tight.  Don't know the history on your engine but don't see why you would replace entire engine for something on the top end.

[59VWSC]

I did pull the #3 spark plug with the truck warmed up and running. Did not note any change in idle  after the plug was removed. Don't have a compression test gage.

[Veeboy]

A compression gauge is a good investment and can be found at most any autoparts store or online form Jegs or Summit racing. If you have a multimeter, it would be good to check the ignition wires to see if you have a bad one. If that ignition wire is good then you have serious problems in that cylinder and should avoid starting and running the car until it is looked at. This is assuming that everything is good at the distributor end.

[59VWSC]

Veeboy!
Great advice on the compression gage. Went out and spent $50.00 for one and found out that compression was at 120 psi in all four cylinders. Probably saved me a fortune. Changed the plugs, wires, disrtibuter cap etc. Still runs lousy. No change at all. I do have a rebuilt carburator on the shelf, so I'll see if thats the problem as I have already repalced the fuel filter and fuel pump. Hopefully this will do it, if not back to the drawing board.

[lovebus (jack)]

what year is the engine?

[59VWSC]

Its an AE case (71) dual port.

[Veeboy]

Distributor tight?  Points in good shape? Valves adjusted properly? Did anyone do work on the car prior to it running poorly?

[lovebus (jack)]

Spray some carb cleaner where the manifold bolts to the heads and around the rubber boots and see if there is a change in the RPM's to see if you have a air leak

[VWPANZER1]

 Pull one wire at a time on the distributor and see if you can isolate it to a single cylinder or the entire bank, that will give you a clue.

  The "Idiot's guide to VW's" has a great sequence of tests to help isolate: not runiing , running badly and all the other ailments.

[lovebus (jack)]

runs terrible, has no low end power, bogs down at low rpm. Eventually, if I feather the gas pedal I will take off.

Running at idle (not in gear), quickly floor the gas pedal, does it bog??

[59VWSC]

Yes it does. You have to keep "feathering" the gas pedal for it not to bog down.

[lovebus (jack)]

Your spray jet is clogged, simple fix but you must make sure it is put back in tightly.

[59VWSC]

Sorry for another dumb question, where on the carb is it?

[59VWSC]

Is it the main jet (adjacent to the Electromagnetic cutoff valve)?