ls14jay

iTrader: (6)

So today after watching youtube how a relay works I figured the 5v going into the trigger of the relay wasnt cutting it. I checked the relay in the fuse box and it too was only getting 5v to trigger it but had 12v on the source side. I found a switched 12v source in the fuse box and used it to trigger the grey wire to racetronix relay. Pump sounded strong. So as long as key is on, I have 12v at pump now. I gave it a pressure test and it went straight to 55-60- psi. Before when turn the key, the pump would prime and get quiet. Does it hurt anything the way I have it? With the return line going back to tank I think its good. After that I tried to get my Innova 5040c to connect to the PCM and it would error everytime. In the past, the rare time it would connect it fired up. So my hopes of it firing up were dashed, but I tried. Needed to hook up the truck and keep it jump startig as I drained the battery working on wiring. After 15 min, I tried it and it felt locked up so I turned the pulley with a ratchet and pipe. No issues. Tried again and it just cranked without even trying to start but this time I think the starter stayed in the out or in position because it just spins wildly now witout engaging. I am highly suspect that the PCM is the whole starting problem now. Everything else on the car seems to work as it should. There are also no security lights on dash that would indicate my Vats bypass has failed. I was tempted to drive my tuck up the hood to see how far over I could get today.

dlandsvZ28

Did you check the 10 gauge wire pathway from the bulkhead all the way to the alternator? Is it still secured tight on the alternator post. Is the tiny red exiter wire to the alternator still connected? Did you check the ground next to the bulkhead? Racetronix actually suggests two good grounds. One at the Racetronix relay near the bulkhead and another from the battery ground to the ground post on passenger side wire harness. A 98 is now twenty years old and grounds corrode over time.

BTW - not related. After many starts and stops after installing an RXP341 (340 lph) pump and new upgraded hot wire kit my 98 would turn over, but not fire. Checked voltage at the battery - only 12 volts with no pressure at the FPR. Did a 10 amp quick charge after reading that to start you have to have at least 12.5 volts to run the pump and to start. After quick charge car started and fired right up and FPR read 58 psi.

ls14jay

iTrader: (6)

I have good voltage on red wire in Hot wire kit to relay. I had the back of the car jacked up so wasn’t able to check at alternator. Ground where racetronix relay attaches at bulkhead looks good. Used it while testing power as well. I guess it’s a safety issue the way I have it wired to ignition if I ever crash. It more of a test anyways which worked. Instant 55-60 psi at test port when key on. Hopefully, but I’m not sure that the relay did require the 12v trigger. It sure seems like it.
The main issue was there was only 5v everywhere I checked. Is the pcm not giving 12v everywhere? Maybe not getting enough voltage to for coils?

To refresh.
With stock injectors after sitting a long time, car would just crank and not start.
Figured I would install the 42lb greens tops I had bought way before and never installed. Also installed truck coils and new plugs. First attempt, fired right up. I shut it off within seconds so as not to wash out pistons untuned for them. Since then, never fires.
Thinking about putting stock injectors back in now that fuel pressure is fixed.
Also wondering about quality of fuel in tank. It was topped off not sure how long ago.
Thanks

AUS Injection

Wouldn't hurt to get those injectors cleaned and tested as well !

dlandsvZ28

Just to make sure.

For kicks, I would check the 10 amp red ign fuse in fuse box near shock tower and and 15 amp yellow pcm fuse in fuse box near radiator. Turn key off, pull both, wait 10 seconds, insert and then try to start.

Johnny_M

Put the stock injectors back in. Get them cleaned at Fuel injector connection in Apharetta, GA. They have great turn around time.

G Atsma

Boynton Beach is in Florida

tech@WS6store

iTrader: (2)

Relays use a 5v trigger from the computer to run the higher voltage higher current side. adding 12v on the trigger side wont add any extra current or voltage on the other side. bypassing the computer part/5v source with a 12v source is not good though as it can shorten the life of the relay.

ls14jay

iTrader: (6)

Wonder why when I had 5v (Factory setup with Hotwire) I could only get 10 psi at best fuel pressure and most cases I couldnt find 12v leaving the relay going to pump and never had more then 5V at the pump wires. Now that it has 12v trigger, it jumped up to normal pressure and 12v at pump wires. So if the pumps runs continuously while key on, does the fuel just return back to tank with the c5 regulator setup on factory lines?
Tonight I got under the front of car. Wires on Alternator seem ok still.I checked all fuses and disconected batery. All look good. I pulled the starter to see why it was just spinning and not engaging which is a new issue since the weekend. Looked fine and put it back in . Upon a test crank it engaged normally but when I tried a second time it was back to spinning up without engaging. Also the fragile little wire running under starter to oil pan lost one side of the connection. Is that oil level or pressure wires? Still cant connect my Inova 5040c code scanner to computer,. gets to 96% and says error. So over the next couple days I will change back to stock injectors in the wild hope that it ever does start I wont have to shut it off right away. There shouldnt be any reason the starter went bad but who knows on this POS now. Maybe pull the plugs even though they are new to see what they look like. Is it possible fuel is just filling the cylinders? When I cant figure out things I tend to think of anything that could be the problem. Could the Full Throttle timing tuner be any issue? Should I disconect that too? I am afraid of messing with too many things at once though. Will also start asking around for a LS1 guy in my area that wont rape me. Great help so far guys, thanks

Johnny_M

There has to be someone in your area here on ls1tech that could help you out. I would, but I'm in Atlanta....

ls14jay

iTrader: (6)

Johnny_M

You need know if you are getting cranking rpm and injector pulses while cranking. I use Efi Live. I don't know if your economy scan tool will perform this diagnosis. You can use a noid light on the injector pigtail to check for pulses. Any part store will loan it.