95 Regal Starting Problems

[tuckerbiker762]

My 1995 Buick Regal has the 3.8 fuel injected engine. It has always
ran great and has only 60,000 miles on it. Recently it began to have
starting problems. If it sits for several hours or over night it will
crank for 10 - 20 seconds before it will start. Before, it always
started instantly. After it does start it runs great...smooth and
normal...power normal. If I am just running into a store or whatever for an hour
or so it starts right up and runs normally but if it sits for many
hours and especially over night the hard starting problem happens again.
HELP! I just had my AC serviced and this starting problem began after I
got the car back. I thought they might have bumped something or forgot
to plug something back in but I can find nothing unusual.

[BNaylor]

Welcome to AF.

Have you tested fuel pressure at the fuel injector rail? You may have a bad fuel pressure regulator.

[tuckerbiker762]

Originally Posted by bnaylor

Welcome to AF.

Have you tested fuel pressure at the fuel injector rail? You may have a bad fuel pressure regulator.

I do not have a test guage..where can I get one? Are they expensive? It does have a test connection. I found a bad vacuum hose on the pressure regulator and changed it but that didn't solve the problem.

I HOPE ITS NOT A BAD FUEL PUMP

[tuckerbiker762]

Originally Posted by bnaylor

Welcome to AF.

Have you tested fuel pressure at the fuel injector rail? You may have a bad fuel pressure regulator.

OK I got a test gauge and changed the fuel filter. When I turn the key on, no pressure, no pump noise. After cranking for 15 - 20 sec the engine starts and runs fine. The pressure goes up to a steady 35#. When I shut the engine off the pressure goes to 42# and holds there. I haven't had a chance to check it after it sits for a while but it will probably bleed down to zero.

[HotZ28]

This sounds like your fuel pump relay is not energizing for some reason and the bypass from the oil pressure sender, is sending power to the fuel pump after the engine turns over enough to develop 20 psig oil pressure. (This is how it is designed) Check the red wire to the fuel pump relay for 12v, if it has power, check the grey wire from the relay to the pump for 12v. Of course, this will apply only when the engine is running, or during prime.
BTW, if you have 12v to the red wire on the relay and none on the grey wire when the prime is energized, change the relay!

[tuckerbiker762]

The fuel pump relay was the the culprit. I noticed the horn relay had the same part # so I swapped them. The fuel pressure came up to 40# with the key on then she fired right up. Problem solved. I was really dreading having to drop the fuel tank down for the pump. THANK YOU, THANK YOU!!!!!