89 Fuel Safety Switch reset issue?

[FRDSHOGRL93X3]

Seems after the car sits for more then a day or so I have to reset the fuel cutoff switch in the trunk (I distinctively notice the missing whir sound of the fuel pump priming when I hit the key). I usually have to whack and reset it 2-3 times to get the fuel pump back on. I've had it happen before and not happen again for 6+ months but its much more frequent now. Couple times a month. Not sure if its a simple as time for a new switch or my fuel pump's on its way out? Any ideas? Also its been doing this occasional random bucking thing at speed afterwards but it clears up...

I recently freshened up the battery, positive battery terminal and replace the malfunctioned multi switch on the steering column. The switch issue was present before I did this maintenance.

 

[luigisho]

These can go bad so that is the first thing I would try. However, have you put a fuel pressure gauge on the schrader valve to check your fuel pressure? Might want to double check that to see if you are in spec. Not sure if a short in the system would trigger the inertia switch or if it is just faulty itself. Since it is so easy to access I would put one in.

https://www.amazon.com/ACDelco-D187...automotive&vehicleId=6&vehicleType=automotive

 

[FRDSHOGRL93X3]

So on Sunday I noticed I had a broken fuel tank strap... The Sunday before that I had it up on the lift for an oil change and it was intact then, so that must have went sometime during the week. Replaced the strap Monday, afterwards went to the deli and had to reset the switch. Later that night driving back to CT from NY I noticed it wasn't doing the bucking thing (yay... almost) but the car shut off at like 70 mph, no warning and I can't get the fuel pump to turn on at all now... groanfest...

 

[luigisho]

Post back when you drop the tank and see what's what in there as far as wiring, sending unit etc.

 

[FRDSHOGRL93X3]

I'm really rusty on my SHO knowledge... for a car I literally drive(drove) everyday for the last 6-10 years I've never had to fix anything... Do the Gen 1's have the large fuse panel under the hood? I can't find it in the 89 or my 90 but I swear I had one in my 93's.
I found some old threads on similar issues that have given me some ideas. Basically its either the fuel pump, CCRM, inertia switch or wiring.

 

[luigisho]

You don't think that tank might have been slapping around on one side over bumps/potholes etc.with only 1 strap or was it able to stay in place? I was thinking a good bump might pop the inertia switch??

 

[FRDSHOGRL93X3]

No I replaced the broken strap prior and tripped/reset switch multiple times. Nada. I even though maybe it was out of gas... nope.
I tried the 89's CCRM in my 90 and it started right up, so its not that. If I run straight voltage from the battery to the connector that goes to the fuel pump it does prime. Not sure if it ran when I grounded the lower right pin on the test connector in the KOEO position cause the f-ing neighbor was leave blowing...
Could it be the CAM position or Crank position sensor? It was doing the intermittent bucking thing.

 

[luigisho]

Ok so I am trying to process this. Does the inertia switch pop itself or are you popping it with a whack and resetting it? How old is the fuel pump?

 

[FRDSHOGRL93X3]

It never "popped" itself. Id hit the key and hear no fuel pump. Smack it with a mallet and reset it and like magic the car would start. If I run power direct to pump it runs, From both the terminal at the test plug and direct to the connector from the inertia switch to the pump (White wire w/pink stripe). Changed round CPS sensor and still no start. I'm at a loss with this thing...

 

[FRDSHOGRL93X3]

I tried to run the KOEO codes on it and nothing, not even with the cheap scanner tool it wouldn't run through the test sequence. Computer?

 

[luigisho]

my ADD is kicking in. What have you done other than fix the tank support?