Vacuum Leak I think

[volvolugnut]

The fuel pressure regulator is mounted on the front of the intake manifold. It has fuel connection and vacuum hose on the front.
You can check the fuel pressure with a gauge teed into the fuel header to the fuel injectors. Should be about 43.5 PSI.
The vacuum diaphragm can develop a leak. A test for leak is to remove the vacuum hose and sniff for fuel smell. You can also use a hand vacuum pump on the regulator vacuum nipple and see if it will hold vacuum.
volvolugnut

[1990Volvo740]

The fuel pressure regulator is mounted on the front of the intake manifold. It has fuel connection and vacuum hose on the front.
You can check the fuel pressure with a gauge teed into the fuel header to the fuel injectors. Should be about 43.5 PSI.
The vacuum diaphragm can develop a leak. A test for leak is to remove the vacuum hose and sniff for fuel smell. You can also use a hand vacuum pump on the regulator vacuum nipple and see if it will hold vacuum.
volvolugnut

Regulator was checked. No Gas smell just Carb Cleaner the day after I cleaned the part.
Car still runs fine but needs the accelerator pedal pressed in the mornings for some reason.

[1990Volvo740]

I reset the computer by leaving the negative off the terminal post for an hour at the car wash.
Nothing changed but the Oil Pressure indicator light began flashing periodically. That might be the problem.
I have no oil leaks under the car, a small one from the valve cover gasket but that should not cause the light to flicker.
I'll replace that sensor and if the erratic idle continues I'll post again unless one of you can think of another issue that can cause the odd morning starts.

[1990Volvo740]

The fuel pressure regulator is mounted on the front of the intake manifold. It has fuel connection and vacuum hose on the front.
You can check the fuel pressure with a gauge teed into the fuel header to the fuel injectors. Should be about 43.5 PSI.
The vacuum diaphragm can develop a leak. A test for leak is to remove the vacuum hose and sniff for fuel smell. You can also use a hand vacuum pump on the regulator vacuum nipple and see if it will hold vacuum.
volvolugnut

I stand corrected. I do smell gasoline in the hose, not the regulator and so from what I can glean from the information above and in other areas I guess the fuel regulator is going out as well.
Both Need replacing.

[1990Volvo740]

I might have another issue.
The throttle plate faces down at a angle and though I tried to clean the plate, I was spraying blind.
I may have a another issue as well. While turning the throttle by hand, with the car not running, the throttle sticks slightly at the 60 percent rotation point.
Using slightly more force gets it to move until it reaches its stopping point but is that normal for the throttle or might I have an obstruction or deformation inside the intake?

[1990Volvo740]

The fuel pressure regulator is mounted on the front of the intake manifold. It has fuel connection and vacuum hose on the front.
You can check the fuel pressure with a gauge teed into the fuel header to the fuel injectors. Should be about 43.5 PSI.
The vacuum diaphragm can develop a leak. A test for leak is to remove the vacuum hose and sniff for fuel smell. You can also use a hand vacuum pump on the regulator vacuum nipple and see if it will hold vacuum.
volvolugnut

The Regulator has been replaced. When I removed it I expected a worn O ring but it was not worn at all. It in fact was just placed in there by someone who owned the car before me and it was oversized.
The car is still exhibiting the hard starting in the morning but running fine / starting fine all day.
The pressure check valve might be next before the car stops altogether.

[1990Volvo740]

Hello All.
I found the problem. It's starting as it should, with just a turn of the key again.

Thanks for all your help.

[matthew1]

What was it?

Hello All.
I found the problem. It's starting as it should, with just a turn of the key again.

Thanks for all your help.