No Spark,no Fuel. Big Problem

[shotyme92]

I bought a 92 SHO with a spun rod bearing, Didn't think to much as to try to start it cause the guy said it worked fine except for the loud knock.

Sarted by gettin it into my garage and confirming the spun bearing by pulling the oil pan. It was indeed spun in fact 3 were totally gone,( well sorta gone, they were mixed in with the oil). Anyway, I bought a new engine and put it in and here is were the problem lies.... I have no spark and the fuel pump does not come on..... I've spent quite some time now along with many friends and aside from starting to buy random new parts and installing we are lost. Has anyone had this problem????? I've come to think maybe its the ECU or a relay of some sort. If you have or have any ideas of what might be occuring please let me know! This problem is literaly causing me a loss of sleep, lack of sexual drive, etc. Please help!

 

[projectSHO89]

Well, the last thing we need are more little Iowans running around...

Chances are, you'll fine either a wiring connection error or a damaged wire connector in one of the circuits that powers either the IRCM or PCM.

Does the CEL come on during bulb prove-out?

Did you reconnect all those wires with the ring terminals to the CORRECT terminal (ALWAYS HOT) of the starter relay?

Start there.

Steve

 

[shotyme92]

i might be inclined to ask as why the last thing needed is little iowans running around???

The starter wires are fine and i have correct voltage to and from the main fuse box under the hood. it cranks over like the dickens but nothing more.

 

[projectSHO89]

Please answer each SPECIFIC question with the specific response. It's usually been my observation that when someone says things "are fine" or "checked okay", they usually are not.

 

[shotyme92]

The wires to the starter are correctly connected as far as i can tell. The previous owner did make a new wire from the starter to tthe battery. But it still has 2 wires from the started up to the fuse block under the hood.

The check engine light does come on when I turn the key on.

I did test the fuel pump tonight and it is working.

I've been looking for bad or damaged wires and connections. I have not found any yet.

What would be a good logical next move?

 

[Sammy~D]

...circuit test stuff it is the eastest way to find bad wires....and for the pump how did you test it??

 

[shotyme92]

If you put a live positive lead to either one of the wires to the fuel pump shut off switch in the trunk it will activate the fuel pump. Easy test without alot of work. And it did turn on and pressurize. I hit the valve on the fuel rail and got fricken wet.

Thanks for the input. If anymore ideas occur dont hesitate, i am willing to try about anything.

I'm thinking about gettin and ecm and a ircm just to test if thats the problem. Going through engine wiring diagrams with a mulimeter just doesn't sound like any fun i want to enjoy.

 

[nemo1080]

I am helping him with his SHO. After swapping the ECM, and Relay controle box, the results are the same. Will crank over and not start. After doing some additional voltage testing I found that the red wire with Green stripe does not bring power to the ECM, Injector ciruit and relay control box, or the cam angle sensor, like it is supposed to. While in the process of tracking that down, I have discovered a few empty plugs on the back of the fuse box, that have metal connectors in them, that have been crimped, but it looks like the wires have been yanked out of the back of it. If anyone could provide me with a map of what fuses control what that would be great! The haynes manual we are using has omited this. We also did discover that if you run a 12v+ lead to the connectors on the relay control box harness, you can activate the fan/fuel pump and each thing individually.. I don't want to damage anything by running too much current through it, so it would also be helpful if there is anyway I could find out what the voltage should be at each pin, for each accessory...

will be back to check after some more tests!

Thanks for the help!

 

[firstgen89sho]

Alright, the best fuse to check is the small 10a fuse in the Engine Compartment fuse box, if that is blown, it will cause no power to go to the ignition system and to the PCM, and would cause a no start condition

the fuses are at the one end of the fuse box (regular sized blade fuses)

 

[SHOMON]

They are actually mini fuses 10a the one on the left i think it says accy. feed.

 

[nemo1080]

anybody got pictutes? mainly of the fuse box, from the front and back, and maybe a list of what fuse is what?

After much trouble shooting iwas able to get spark, but unhooking the relay control box and jumping power to the redwire with green stripe.. this wire is largely responsible for spark, but for some reason, there is only ~.4 volts at the Yellow wire (ecu constant), red wire/w green stripe, and several others. the injector circuit, maf and all other plain red wires are getting the 4 volts they are supposed to. what would cause the power to go from ignition switch, to fuse box then just dis appear,? when ALL the fuses are GOOD. so are all the relays. My theory is that it has something to do with the way the red wire w/green stipe goes in the fuse box, through the fuse, but when it comes out the other side, after the fuse, it is red with a yellow stripe. WTF? is it supposed to be like this? did someone screw with his fusebox??!??!?!?
pictures or some good wiring diagrams would be really helpful. thanks!

 

[projectSHO89]

good wiring diagrams would be really helpful.

Here's a start.

 

[projectSHO89]

Limit files as attachments to three so here's some more.

That should give you everything you need.

 

[nemo1080]

word. thanks! I'll use that when i get back to the Sho this weekend!! Will post results asap! wish us luck!

 

[shotyme92]

thanks for the help guys.. we need it.

 

[nemo1080]

bump.
still no progress.
if we hard wire the ignition circuit, we can get it to start, but only if we spray fule into the intake, from a spray bottle. cannot get injectors to open or anything to work witout "rigging" it.
seems that the ecu doesn't have power but we can't figure out what wire needs to be hot to turn it on...

 

[nemo1080]

here is a diagram of what all wires we have jumped power into.
this turns the fuel pump/fan/ignition system on, but no fuel injectors...

car will start if you spray bottle fuel into the intake while you crank it, then continue to spray fast once it fires up... when it does run, it runs at like 11.8 volts, so the alt. is involved somehow???!?!?!

 

[AREA 91]

Did you connect the ground wire that sits under the fuel rails? It is a 10mm bolt that threads into the top of the block near the knock sensor.

 

[nemo1080]

pretty sure the engine is all grounded well... but we'll check!

 

[projectSHO89]

Make certain the three fuse links that mount to the starter relay stud are on the correct one (the HOT battery lead, not the starter-lead side).

Steve