speed bump=no run

[Cdnone1]

I drove over a speed bump going to pick my son up last night and the motor just quit after about ten feet. I'm thinking must be electrical in regards to the fuel system. The car has plenty of electrical to the lights starter etc.
I was going to check the fuel pump relay (even though it is new along with the fuel pump I installed a few months ago) then pull an injector to see if it's getting fuel.
Anyone else had this happen and would like to chime in and maybe save me some time I would appreciate it
Thanks
Steve

[Gemballa2006]

Probably knocked a ground off. That's what I would check first

[Cdnone1]

Which ground?

[James Brown]

LOL that's the question!! Go through a no start check list and see what you find, ignition, fuel pump, ign. switch, battery, fuses, relays. Pull the relays and check for corrosion and twist fuses for the same reason. Bumps might dislodge both power and ground throughout the car.

[b rock]

check the fuel relay in the front fuse block. it may have been jarred loose.

[Bob Kontak]

+1 on fuel relay - Closest one to the master cylinder.

[SCOTITUDE]

Originally Posted by Bob Kontak

+1 on fuel relay - Closest one to the master cylinder.

+2 BTDT
when i was a new owner before the internet. a day of scratching my head and wondering what i got myself into. pcar friend came over to help. i pleaded my case and he opened the hood, pushed the relay back in that had come half out and she started. cost me a flatbed ride home. wire tie the relay into the socket to keep it from bouncing out.

[Rich Lambert]

Check for loose screws on the fuse holders too.

[Cdnone1]

Thanks
So I had a few minutes to look at it this evening before the sun went down. (The car was towed to the street in front of my house.)
I replaced the fuel relay with what was a good relay months ago that I just replaced when I put in the new fuel pump. Checked the fuse, cleaned up the contacts. Opened the engine compartment. Turned key on and can hear the CDI box buzzing. Lifted plate in the airbox and made the correct buzzing sound.
Pulled the #1 injector line at the injector, put into a safe container turned key on lifted air plate and no gas coming out of injector line.
Any idea 's where to start in the morning. Anyone know how to check the relays to see if there good even though I don't think both would be bad.What about checking the relay mounting holes on the fuse box. I'd like to take the car to a football game tomorrow afternoon so I would like to fix this quick
Thanks for the input
Steve

[Joe Bob]

What engine?

[Cdnone1]

Sorry guys
It's an 82 SC with (obviously) a 3L

[Joe Bob]

OK....you have fuel, pump running, got spark?

If so, tried popping up the flapper valve in the air box?

[Cdnone1]

Originally Posted by Cdnone1

Thanks
So I had a few minutes to look at it this evening before the sun went down. (The car was towed to the street in front of my house.)
I replaced the fuel relay with what was a good relay months ago that I just replaced when I put in the new fuel pump. Checked the fuse, cleaned up the contacts. Opened the engine compartment. Turned key on and can hear the CDI box buzzing. Lifted plate in the airbox and made the correct buzzing sound.
Pulled the #1 injector line at the injector, put into a safe container turned key on lifted air plate and no gas coming out of injector line.
Any idea 's where to start in the morning. Anyone know how to check the relays to see if there good even though I don't think both would be bad.What about checking the relay mounting holes on the fuse box. I'd like to take the car to a football game tomorrow afternoon so I would like to fix this quick
Thanks for the input
Steve

No fuel at the injector line, lifted flapper

[Joe Bob]

Is the fuel pump buzzing when the ignition is turned to the on position?

[James Brown]

Hear that??? The sound of silence, fuel pump that is...

[boyt911sc]

Originally Posted by Joe Bob

Is the fuel pump buzzing when the ignition is turned to the on position?

FP's for SC's don't run at ON/RUN position!!!!!! And if it does, there is inherently wrong in the wiring set-up. Test the FP and FP relay separately to determine if they are good.

A very simple way to test the FP is by jumpering terminals #87A & #30 (FP relay socket) with the ignition @ ON/RUN position. If the FP fails to run, the're several possible causes to check; wire connections, ground supply for #85, bad FP, etc.

Lastly, check if the FP relay's magnetic coil activates when energized or get a known good relay for the FP test.

Tony

[1990C4S]

Originally Posted by boyt911sc

FP's for SC's don't run at ON/RUN position!!!!!! And if it does, there is inherently wrong in the wiring set-up. Test the FP and FP relay separately to determine if they are good.

Correct. But his fuel pump should have run when he lifted the plate.

So if you can't hear the pump running you need to do what Tony says above. Either figure out if the relay is energized and closing, or slide under the car and measure the voltage at the pump with the plate lifted.

Possible issues: bad pump, no ground on pump, no +12V to pump, (possibly the air flow switch is preventing the f/p relay from coming on? IIRC)

[Cdnone1]

Crap
I can here the fuel pump running when I lift the plate.
Pulled the #1 injector line, lifted plate and no gas.
Pulled the line from the fuel accumulator to the filter and hooked up a line. Lifted plate and no gas!
Got to be a bad pump , right?!
I just replaced this pump 7 months ago!
Damn. The first pump looked like it lasted 26 years and the second one lasts 7 months!
And I just filled the tank!
AAARRRGGGGG

Steve

[Joe Bob]

The pump could have knocked something loose in the tank and clogged the line.....btw, I still run my old SC fuel pump even though the 3.6 uses a lower pressure. It runs all the time when the ignition is on. In an earleir post I DID suggest lifting the flapper, just wasn't clear in my followup.

[boyt911sc]

Originally Posted by Cdnone1

Crap
I can here the fuel pump running when I lift the plate.
Pulled the #1 injector line, lifted plate and no gas.
Pulled the line from the fuel accumulator to the filter and hooked up a line. Lifted plate and no gas!
Got to be a bad pump , right?!
I just replaced this pump 7 months ago!
Damn. The first pump looked like it lasted 26 years and the second one lasts 7 months!
And I just filled the tank!
AAARRRGGGGG

Steve

Steve,

To test your FP, you need to measure the fuel pressure or the volumetric rate per unit time and the current draw. But most important of all, there should be sufficient free flow of fuel from the tank to the pump.

Even a good FP would fail the volumetric flow test if there is severe flow restriction from the fuel tank outlet. Assuming that the fuel is flowing freely out from the fuel tank outlet, a good FP should be able to develop the required minimum flow rate (example: 1 liter/30 sec.) as per specification.

Bench test the FP, before condemning it as defective FP. I like to use both fuel pressure and current draw tests for determining the condition of a CIS FP. BTW, do you have a Bosch FP? Keep us posted.

Tony