95 z28 wont start
 

I replaced the opti and opti seal, plugs and wires, water pump and pump drive seal. My car ran bad before i changed everything. I finished up and cranked it a few times and fired right up a little rough at first, but it idle out nice and smooth. i shut it down and came back out to go for a drive and now it wont start, it just cranks. I hit the schrader valve on the fuel line, and barely get any gas spewing out, shouldnt i get a good spray with around 40 psi or is my pump shot. I dont have a pressure gauge to check it with and the fuel filter looks to be brand new.

Re: 95 z28 wont start
 

You need to measure the fuel pressure. You can't guess by how hard it sprays out of the valve. Most auto parts stores will lend you a gauge, with a deposit. On the other hand, it's a $35 item, that is a good tool to have in your tool box.

Did you do any diagnostics before replacing the Opti? Did you have any codes related to the Opti? Wouldn't hurt to check the codes.

Re: 95 z28 wont start
 

Im only getting around 15 psi at the valve. Ill be borrowing a scanner from a guy i work with tomorrow and gotta wire it up like i saw on SHBOX's site. I keep blowing the #10 under hood fuse for the injectors. It had a 20 amp in it and when i throw a 7.5 in, it blows instantly.

Re: 95 z28 wont start
 

so whoever owned this car before me wired the fans up to come on with the ignition and they used the #10 underhood injector fuse to get there power, which i assume is why it had a 20 amp fuse in it and why it blows when i put the 7.5 back in

Re: 95 z28 wont start
 

The fan motors are powered directly from the + terminal in the red box by the battery. The line is protected by a fusible link. Typically all you need to do to power them from the ignition would be to connected the switched ignition source to the control side of the relays, a low amp draw. Are you sure they powered the fan motors directly from the injector fuse?

I'd return the fan motors to the direct wire, via the relays, and let the PCM control the relays, based on the coolant temp readings.

You would have a stored code for each time the injector fuse blew, and possibly two codes for the botched fan relay control wiring. Have you been clearing stored codes?

Re: 95 z28 wont start
 

Yes i am sure i have like 5 of my friends stumped trying to figure out why they would do it this way. I pulled off the wire that they ran, just to see if it would start and if runs like a champ. Im going to rewire fans

Re: 95 z28 wont start
 

Now that i have the car running i've been looking into the wires going to the cooling fans to try and figure out why they have been rewired. Im not finding any burnt, pinched smashed or bad wires, but Im not getting power to pin D1 on the #1 relay which should be live if i've been reading correctly. What would i need to do to replace the fusible link, can i use any fusible link along the correct gauge wire??

Re: 95 z28 wont start
 

I assume you have looked at Shoebox's cooling fan wiring diagram (all 95's are "late production"):

http://shbox.com/1/fan_schematic_1995.jpg

Have you checked Relay #2? The fusible link provides power to both pin D1 on Relay #1 and pin F4 on Relay #2. If you are only missing power to Relay #1, the fusible link has to be good.

The fusible link is at the red "+" terminal box. The 96 manual shows that link C supplies the fan relays. I don't know if 95 is the same. I don't know if they are labeled with a letter. But they do show the size of the link. Shoebox has a photo:

http://shbox.com/1/fusible.jpg

Re: 95 z28 wont start
 

Yes ive been checking out his diagrams, and im sure there is no power coming through the red wire #402, Im checking from the backside ive got the fuse box and wire loom open, and Im also sending power backwards from the end at the fuse box and im getting nothing on any of the fusible links.

Re: 95 z28 wont start
 

Ok so now my car wont start again. It fires up but as soon as i let off the key/ disengage the starter, it dies. I can try and give it gas to keep it running but it falls flat as soon as i hit the gas pedal. To go over what i have done so far; new plugs and wires, delphi optispark, water pump and pump drive seal, delphi fuel pump new fuel filter and BWD fuel pressure regulator, Im wont have a chance to check for codes until monday but im not getting the service engine light. I am getting the security light but it goes off as soon as the car fires up. Im thinking it may be the ignition switch but im not sure, im going to keep on reading into this

Re: 95 z28 wont start
 

There are "fatal" codes that do not turn on the SES light.

Re: 95 z28 wont start
 

i tested my icm and opti harness today Im reading around 75ohms on the icm harness with the key on and 0 ohms with the key off and around 160 ohms on the opti harness with the key on and 0.1 ohms with the key off. All of the voltage is accurate.

Re: 95 z28 wont start
 

What voltage do you get on the white signal wire to the ICM, and on the high and low res signal wires form the Opti, with the engine cranking?

Re: 95 z28 wont start
 

Sorry i haven't been able to respond. It turns out the multimeter I was using was crapping out. I downloaded Scan9495 if anybody could look over my data i would greatly appreciate it. this is just a start up and idle. I took a few cranks and i have to give it gas to keep it running at first.

http://www.mediafire.com/view/etkkl5...p_and_idle.csv

Re: 95 z28 wont start
 

Can't download, without installing an .exe setup file (which it tries to do when I click "download"). There has to be some way you can make this file available without that step. I've downloaded numerous .csv data logs from mediafire, without the necessity of exposing my PC to a harmful .exe file.