I have a White Magic 1200 pro. When I start a job & switch to vaccum the rpm's don't pick up even though the belts are turning. This started happening in the winter, even though the truck is garage kept, but now it's happening no matter what the weather. It will take any where between 5-15 minutes before the rpm's kick in. It seems to be getting worse. Any ideas on what the cause may be? Thanks
It depends on the year of the machine. On my 1987 pro1200 the vacuum advance will slowly bring the rpms up unless you hold the vacuum hose closed and then it powers up right away. On my 2003 unit it fires up with a 2 second delay because it has a manual throttle assembly. On newer units it is all electronically controlled and fires immediately. Just press on the van accelerator pedal and it will go right up to the desired rpms on any unit. If you need to cram a stick on the gas pedal that will be your ghetto repair until you get it fixed at your local TM repair facillity.
We have 7 of these right now and they in one way or a another they all have had a issue like this. I would check the little red plug on that connects into the diagnostics plug, they use a zip tie to hold it in place and the plug needs to be clean and in all the way for it to work. Also you can reset the computer (assuming it is electronic and not mechanical) if you need to by unplugging it for a few minutes. I also have one truck that you have to pull up on the brake pedal just for a second to get the switch on the brake to open all the way. You can also check that the wire to the parking brake is in good shape, sometimes it wears out. If you turn the machine on and it is electronic when you look under the dash you can see the Module light up, if it is the module certain lights will be blinking to show you an error code (Although i don't know them off hand). Either way it sounds like something around the throttle control module. Just to be safe I would check the belt under the hood to make sure it is not off a little. Good luck
