Dzrt1st

I have an ’85 GSL-SE that I bought last summer that is completely stock and has always fired right up and runs great.

I’m having the issue of no power to the fuel pump when trying to start the car. I have gone through a lot of the older threads on this issue but no have had no luck finding the problem.

This issue started last weekend when I started the car after it sat for about a month. I cranked the engine over and it fired right up but the battery seemed a little low (slightly slower cranking speed). I turned it off and put the battery charger on to top off the battery. Couple hours later I went to go for a ride and it cranked over as normal but now it won’t start.

I have checked the following per LongDuck’s tutorial found in earlier threads -

No power to fuel pump when key is on or when cranking. The tach needle bounces while cranking. I hotwired the pump from the battery to the fuel pump connector located in the bin and the pump runs. After running the pump for about 30 seconds I disconnected the hotwires and tried starting it with the key and it fired up for two to three seconds, so I know it’s getting fuel (and spark) when the pump runs.

I figured it was a bad Circuit Cut relay by the ECU so I replaced it but, nope. The relay clicks when turning on the key.

Tried the “shunt on the T connector near the AFM” trick but, nope.

Checked the AFM door and it moves freely and the relay clicks when pushing on the door with the key on.

Tried the jumper on the Cut relay plug, no joy.

The two round main relays near the MC click when turning on the key.

Checked all fuses.

Removed and checked all five fusible links. All have continuity.

I feel the problem started when I put the battery charger on it (even though I’ve done it several times over the winter).

Any more help would be appreciated. Thanks

RX7_Renesis

iTrader: (1)

If you didn't allow enough time for the engine to completely warm up before shutting it off .. maybe the engine is flooded?

Try pulling the spark plugs out .. check to see their condition (wet, worn out, improperly gapped, etc.) and then try to restart using the "flooded engine restart procedures".

LongDuck

Alright, may have more questions, but here are some quick things to look over; when you say you checked all fuses, did you pull them out one-by-one and put a multimeter across them? It's I portant, as some of these blade fuses can burn out at the arm and visually look fine. If you have a blown fuse somewhere, it could be an indicator of a short in the wiring harness, and is worth looking closely.

Check your grounds throughout the engine bay, specifically at the negative battery terminal to body by the driver's side strut tower and especially at the starter. Check that all of the nuts and bolts are tight and that the connections are clean and shiny. Don't use sandpaper, as the silicone grit can imbed in the metal and cause a poor connection. Further, test not just continuity of the positive and negative battery cables, but also for resistance; as these age, internal corrosion can lead to high resistance that will lead to all kinds of electrical problems.

Lastly, you should be running Denso BR8EQ14 plugs on both leading and trailing ignition. Any other plugs can lead to fast fouling and will seem like you're not getting spark (*because it's flooding). New set of plugs, Cap and Rotor are good medicine, and from there, we can start looking at ignition and fuel injection.

Dzrt1st

It’s alive!
After checking all the fuses and cleaning the grounds on the neg cable still no luck in starting. So I figured the next step was to trace the wires from the fuel pump. I removed the drivers door sill cover and found that the blue/ green fuel pump wire had been spliced into and two wires run up the kick panel to the dash.



Tracing these wires led to a switch under the dash just left of the steering column that was installed by a previous owner. I had never noticed this switch before. I flipped the switch and the car started right up as normal. I must have hit the switch without knowing it was there. Apparently it is a kill switch or anti-theft device of some sort.

Thanks for the helpful suggestions for narrowing this down.

LongDuck

Good job tracing it down to a kill switch. I'm not a fan of crimp terminals used in this fashion on such a critical circuit, but if it's worked thus far, I'd leave it alone. The kill switch itself needs to be a robust, mechanical switch in good shape. Loss of fuel pump circuit power in traffic would be inconvenient and potentially dangerous, so place the switch somewhere that it won't be accidentally activated, and where only you know the location. Clearly it's an effective means of keeping the car from being driven off! Take care,