300 CE Fuel problem
 

I have a non computer friend that is working on a "88' 300 CE and here is the problem. Car starts fine COLD but starts hard when WARM with the following antics, "sputters and bucks for sometimes, 5 minutes. He has changed fuel filter (nasty) and fuel check valve. There are two fuel pumps in series, could one be not working? and is there a way to check the fuel pressure regulator? And if anyone has any other ideas that would be great. Thanks much
Have a good evening:)

"Fuel leakdown" causing "vapor lock". Possible causes could be "accumulator", testing "fuel pump" draw for proper amperage (one pump not working) or bad "fuel pressure regulator".

Pull the fuel pump relay (behind battery) and test the amp draw with an ammeter or a multimeter between pins 7 and 8. The proper range is between 6 and 8 amps. Anything more and you probably have a bad pump.

To test the FPR, pull the vacuum line off and see if any fuel is leaking out. If so it needs to be replaced. You can also check the fuel pressure at the fuel return line coming from the FPR for proper pressure. I forget the specs.

Do a search on any/all of those topics and you'll have enough to read for days.



GL