Mauiguyy911

1995 Chevrolet Z28 is the car:

Drove the car to the store and started and ran fine. After getting home tryed to start it up again and it wouldnt start. Fires and is getting fuel and have tryed replacing the coil, wire, and ICM but still doing the same thing. Turns over fine but just wont crank. I was told by a shop that it isnt showing any codes and that the spark seems to be getting to the opti but is not getting sent to the plugs??

Im thinking crank sensor or opti? got any ideas...And if you think it is one or the other does anyone have a page with some diagrams ect so i can change it out..thanks ahead of time for any help.

ArizonaZ

just had the same problem this past week. check you fuel pressure. My pump went out and did exactly what you are describing.

Mauiguyy911

i will see if i can go get my hands on something to check the fuel pressure..but i can hear my fuel pump turn on when i turn my key to the on position? could it still be the problem even if its turning on, maybe the fuel filter?

ArizonaZ

even if it is turning on, if it is not producing the right pressure it could be the culprit. you can get a fuel pressure tested at an autoparts store for under $50, or someone told me autozone rents them (loaner tool). I bought one as I figured it might come in handy in the future. its also worth checking now to make sure you are not buying unneeded parts.

Do a search to find what the required pressure should be. if I recall its about 43 psi at idle but that might be off.

Mauiguyy911

Well my buddy just checked the fuel and said it was fine..? i have no idea what it could be as of now except for something like the opti or crank sensor but really dont want to take everything apart if i dont have to

Mauiguyy911

ok so we got the opti out and shook it and sounded like something was very loose inside..got two of the star bolts off and peeked inside and looks like the rotor is broken..is there any way to just replace the rotor and parts inside without having to buy the entire new opti???

Wolffman

MSD makes a cap and rotor for it. Look on the Summit web-site. If I were you...and already had the OPTI off the car, I would change the whole unit.

Mauiguyy911

Yeah, i def would rather do that but im pressed for time as i need it done by tomorrow and dont have the $400 for the whole unit but got the cap and rotor by AC Delco for $130 which i had the money for...i just wanted to make sure that i could just change them out and it would still work...plus it actually only took me 1.5 hrs to get the opti off w/some the right tools well now i just have to hope that it starts up tomorrow

By the way, does anyone know where you can get a tool to take the 4torx (star) scews off that hold the opti together..cant find it anywhere?

Guest47904

If memory serves, the throttle body screws can be used as a tool for them. Put 2 jam nuts on the end of the screw, then you can put it in socket or nut driver to use it without damaging the threads.

Mauiguyy911

wish i would have seen this earlier! i would have never even thought of using those..i eneded up just pretty much drilling out two and using some vice grips for the other two and switched them out to a flat head screw so in case i ever need to get down there again i wont have to worry about it.

Mauiguyy911

Well, it ended up being that the rotor inside the opti was in about 50 pieces so we bought a cap and rotor, got it all back together and started up great!

Bad thing is that about 10 minutes after driving the car to test drive it my waterpump went on me and started shooting coolant everywhere from the pee hole on the bottom back of the pump...can i ever get a break!

And just to make sure..if its leaking like that, just means i need a new one right?

Javier97Z28

Yes.

The Engineer

Put some good thread-locker on the rotor screws so they don't get loose (I've had that problem a few times). Did your rotor just break-up on its own, or did the screws get loose and hit the cap contact posts and break?

We need to start a forum tech-rating system based on the number of Opti removal and replacements you've done. I could be the record-holder.

WD