i have a 97 that set cranksenor sn cam sensor codes replaced both still no start borrowed a snsp on to acess computer but could not so i replaced the logic module still no start need advice

 

You may want to ck the flex plate ( same as flywheel ), it may have broke and can not pick up a signal or a wiring problem.

 

checked flex plate its ok replaced logic module still np start anymore sudjestions

 

Well, it's probably time to go back to the basics and see if you have fuel and spark. There is a shraeder valve on the fuel rail that looks like a tire valve. I would crank it for a few seconds and then carefully depress the valve to see if fuel squirts out--be carefull and have a rag ready. If you have fuel, then I would disconnect a plug wire and have someone crank it to see if you have a spark to ground. In fact to be safe, check for the spark first

 

I have 140,000 miles on the car. In great shape,but it has started to guzzle oil a bit.I intend to hold on to it for a while longer, would there be any point in switching to synthetic oil at this point? Would it harm the car? Or would it possibly address the oil issue? thanks

 

I'm a fan of synthetics, but I've also experienced higher oil consumption with older cars. Also, depending on why your van is burning oil, synthetics can leave some nasty deposits when it burns. Personally, i wouldn't spend the extra money in this case.