Fuel pressure gauge to lend in LA?

[Cdnone1]

Does anyone have a fuel pressure gauge in the LA area they would be willing to lend me. My car all of a sudden wont start.
Checked for spark at the plug, OK. Pulled the coil and tested , OK. All fuses are fine. Lifted the pressure plate and pump is buzzing.
PLug looked like the car has been running a little lean , so I'm thinking incorrect fuel pressure
Thanks
Steve

[ossiblue]

Sudden and complete failure to start is not typical of out of spec fuel pressure--that usually develops gradually and gets progressively worse. This is not to say you shouldn't check the pressures, but it sounds like it could be some other problem. You have spark so fuel is your next place to look but your car may have some sensor that prevents starting (I'm not familiar with the later cars.)

So, just to be clear, a few questions:

Did this truly happen all of a sudden--like one day it just didn't start?
Can you get it to eventually start?
If it does start, how does it run when cold and how does it run when warm?
Do you have a pop-off valve and is it seated and sealed?

If you can post some more information about what is going on, it may help.

[Cdnone1]

Thanks
Here's a little back story.
82 SC.
It was lightly raining, more misting really when I drove the car about 1/2 mile to the store to pick up a few things. I was in the store 5 minutes and came out. The car started up (like always ) but died within a second.
I cranked it several more times, left it for 5 minutes and tried again. Same thing lots of turning over but no start.
So I left the car there and had it towed back to my house later that night. The car sat for 4 days in dry weather while my wife and I where out of town.
So I started trouble shooting
I took the battery in and had it tested. It was fine and they trickled it to a full charge.
Hooked the battery back up. Turned on the ignition and can hear the CDI buzzing.
Thought it might be the coil so I pulled it and ohm tested it and it was right within specs.
Pulled a plug and ground it and turned the car over and there was spark.
So I figure fuel.
I turned on the ignition, lifted the plate and can hear the fuel pump buzzing.
I figure it might be the fuel pump, don't have access to get under the car easily from the way it was left in my driveway after the tow.
So rather than test the pump for current I wanted to see if it was putting out 75psi.
I'm all for idea's on things to check, but I can only get about 20-30 minutes a time to check things.
Thanks
Steve

[ossiblue]

OK, good new information. One thing stands out that needs clearing up. You say you "lifted the plate and heard the fuel pump buzzing". The important thing is--did you hear the injectors squeal? If not, that's likely your problem. Something is blocking flow to the injectors--clogged line, clogged fuel filter, clog in line to fuel distributor (not too likely.)

The fact the car started immediately and then died, supports possible fuel starvation too.

Let us know.

[boyt911sc]

Originally Posted by Cdnone1

Does anyone have a fuel pressure gauge in the LA area they would be willing to lend me. My car all of a sudden wont start.
Checked for spark at the plug, OK. Pulled the coil and tested , OK. All fuses are fine. Lifted the pressure plate and pump is buzzing.
PLug looked like the car has been running a little lean , so I'm thinking incorrect fuel pressure
Thanks
Steve

Steve,

You could test your FP by either fuel pressure, flow rate or electrical (amperage). Since you don't have a fuel pressure gauge kit, your next option is flow rate or amperage. Take several measurements for 30 seconds run. Flow rate per minute will be twice the quantity you'll be getting. A 2-liter per min flow rate is ideal. Or measure the amperage the FP is drawing while running. Values between 4 to 6 amperes are considered within spec. Personally, I find the pressure gauge more reliable and convenient to do.

Tony

[Cdnone1]

I was thinking I would start by pulling the number 1 injector line and see if its putting out fuel.
Any advice on how to clean out the lines and fuel distributor if there clogged?
Steve

[ossiblue]

Originally Posted by Cdnone1

I was thinking I would start by pulling the number 1 injector line and see if its putting out fuel.
Any advice on how to clean out the lines and fuel distributor if there clogged?
Steve

That's a good first step, IMO. If you find no spray from the injector you've nailed the problem. If that's the case, you might then disconnect the fuel line where it enters the fuel filter and see if the line is full of fuel. Then, put the end into a jar and carefully lift the plunger in the throttle body (or have an assistant do it) and see if fuel shoots out into the jar--you'll know immediately. If so, the clog lies within the filter or further downstream. If no shot of fuel, the problem lies with the pump or the line to the filter.

If you do the above test, proceed with caution and have a fire extinguisher close.

[MrShades]

Have you checked that you have a spark?
My car was just like yours a couple of years ago and it was a faulty/broken wire in the distributor on my car.
And off course it is not original Porsche CDI box on mine so that took some time to get the right parts.

My car started and died several times before it shut down. Take off the distributor top and cehck the electric wires.

[Cdnone1]

Thanks
Yes I checked the electric (see above)
I pulled the number one injector and no gas. I separated the injector and checked the line separate and still no gas. I check the injector and it is working fine.
I pulled the input line from the accu to the fuel filter, ran a hose from it to a catch jug and ran the fuel pump. No gas.
I checked the fuel pump by listening for sound. That was OK. I checked the 86 and 87A on the fuel pump relay and there was power.
So I have come to the conclusion that the pump has suffered a catastrophic failure.
I am going to replace the fuel relay, fuel filter and fuel pump. I have ordered the parts from Pelican and will jack the car up tomorrow and swap out the pump, relay and install the new filter.
Anyone have any other idea's?!
Steve

[ossiblue]

Honestly, I think you've found the problem but there is the possibility that the filter in the tank is clogged. To check it you will need to drain the tank, or at least drain it down so the area under the plug on the bottom is free of gasoline. Unscrew the hex plug and carefully remove the filter element. Be cautious as it is fine mesh nylon and cannot be repaired. If it is clogged or partially clogged, it should be replaced.

Admittedly, a clogged filter in the tank in less likely than the pump itself to produce absolutely no fuel to the engine, but it is something to check/replace while "you're in there." Also, you may wish to blow air through the line from the filter to the pump (once the pump is disconnected from the line) just to be sure there is no clog in the line.

[sammyg2]

I have a CIS fuel pressure test kit that's almost brand new. You can borrow it providing I get it back

Onlyist problem is, it's in Orange near the 55 and 91 freeways. that's a fur piece from L.A.

lemme know.

BTW, I also have a bolt with two nuts jammed together on it real tight. The head of the bolt fits real nice in the drain plug in the gas tank of my 911 and a wrench on the nuts works real well to remove the plug, just in case you don't have the proper wrench to get it out.

Come to think of it, I might have a good allen wrench that size too, hard to say.
Porsche tools have a habit of accumulating. And hiding.

[Cdnone1]

Thanks guys
I have the car jacked up and supported, the belly pan off and am just waiting to to see if the parts arrive tomorrow.
I couldn't find out how to ohm check the fuel pump relay so I'm going to just replace it first before I pull the pump and see if that solves my problems
Thanks for the input and suggestions
Steve

[vash]

grab another relay, even a black one and move it over to the FP relay position.

[Cdnone1]

Thanks guys it's all fixed
I replaced the fuel pump and put in a new relay. Purged the air from the line to the fuel filter, hooked up the fuel filter. Turned the key and she fired right up!
Didn't think a fuel pump could catastrophically and immediately fail like that

Steve

[ossiblue]

Originally Posted by Cdnone1

Thanks guys it's all fixed
I replaced the fuel pump and put in a new relay. Purged the air from the line to the fuel filter, hooked up the fuel filter. Turned the key and she fired right up!
Didn't think a fuel pump could catastrophically and immediately fail like that

Steve

Always good to hear of something getting fixed...congratulations! And thanks for posting your results as it helps anyone in the future who has similar problems. You'd be surprised how many times we never hear the conclusion to problem investigations.

Job well done, Steve. Now get out and drive the sum'bit*h