Changed alternator and battery, still running rough,electrical items not running full strength

You may have blown a fuse. If you can start the car, and you have a volt meter, check the battery voltage before you start the car and after it’s started. Should be 12v roughly before starting and around 13.8-14.4 while started. If the voltage goes below 12v your alternator isn’t charging the battery

If the electrical items are operating very slowly and the battery light is on,you may have a charging problem.Recheck voltage at battery positive terminal and at alternator output terminal with engine running,you should see around 14.5v at both.

Sounds like the new alternator is not charging the battery. Once the battery drops below a certain level the car can't keep its components (on board computer) running. The ignition is now running off the battery which is fading. Soon the car won't be running at all.

As already suggested, check belt and new alternator.

If you are meaning that the engine is running rough or inconsistently it may be because of a faulty battery not supplying consistent charge. This may also be because of a electrical short, alternator, or ignition issue.

Hi, first thing to do and if you know location of the fuse box take light tester and test each fuse may you find some fuses blew. change theme first. if you change the fuses and the the problem for each item you describe still on that mean damage went to the items you say.

No. All an alternator does is replenish your battery charge.
When you changed your alternator you may have shaken loose buildup in your intake.

Cheap version is to clean your intake (spray it with intake cleaner)...change your air filter and put two bottles of injector cleaner into a full tank.

Give it the time to burn the fuel before trying anything expensive.

Or more accurately: an open somewhere...

Be certain to full charge and load test the battery, clean battery connections with rough sandpaper.....

It is these items that are perhaps 95% of this type of complaint are found.

Sure..you need to get a volt/amp tester to verify alternator strength. If that is OK then each one of your circuits has to be checked for too much electrical draw. It sounds like that is your problem because as you run the car the alternator takes care of your electrical needs; however the battery takes a hit each night if one or more of the circuits is drawing too much juice.

Sounds like your alternator is starting to seize up. Remove the belt and spin the pulley by hand. If you hear a light grinding sound or the pulley is stiff then the alternators bearings are worn. Take the alternator to an electrical repair shop for rebuilding. I usually pay around $50 as opposed to $100 or more from a parts store. Look up auto electrical repair in your Yellow pages. Older VW's are known for starter and alternator failures so finding a cheaper source for parts should help you save some money.

What initiated the need for jump starting? Is the alternator charging? Has the battery been checked?

To check the alternator, once the engine has been jumped and is running, remove one of the battery post connections. If the engine dies, the alternator is not charging the battery, and the symptoms you describe are the on-board computer going through low voltage spasms until sufficient electrical power to operate the engine / tranny is drained and the car dies.

If the car continues to run with no battery attached, the alternator is charging - - - and I would recommend removing the battery and having it checked and (if good) recharged to full capacity. I would also recommend having it charged even if the alternator is the problem just to delay the onset of the low voltage problems. The car should operate normally for a few miles before the battery drains too low after a full recharge, enabling you to get it to a shop for alternator service / replacement.

If you attempt replacing the alternator yourself, make sure the battery is disconnected prior to starting the job. Saves blowing up good stuff by accidental short.

Hope this helps and good luck!

-WB.