iroc1793

iTrader: (2)

Spent this weekend wrapping up my wiring or so i thought. I got my engine to turn over, but i have no fuel delivery, or spark. I believe i have my battery terminals hooked up correctly, i have a chassis ground and a engine ground from the negative terminal, and from the positive a wire to the starter and one to the alternator. I have spliced into the pink wire under my dash for the ignition wire, i have the s-terminal wire from the C100 connector down to the starter.

Im not sure if it makes a difference but im using the painless harness i got used off another board member, and in the harness it had two red wires labled B+ on starter, so i ran those there aswell.

I connected my fuel pump wire to the tan wire behind the upper back seat of the car to the tan wire. The fuel pump would not run with the key on or attempting to start the car. I tested that wire to see if the pump was bad but when i ran a seperate wire right to the battery the pump worked so the pump isnt bad. I tested the fuel pump for power at the terminal that is labled fuel pump test on the painless harness by the fuse box and there was no power there.

I checked for spark and i have no spark, so i disconnected the connector going down to the opti and tested for power there and i also have no power there.

Im not sure what is going on. I hope i didnt fry the pcm somehow. im not sure if there is a sensor on the engine that wont let the pcm provide fuel and spark if it is faulty or not. i know some cars rely on a crank sensor for fuel/spark. any help would be appreciated guys. thanks in advance

BCdawg57

iTrader: (1)

Do you have power to any of your sensor plugs with the key on?
If you have no power at your opti and your fuel pump wont run..are you sure you have the power hooked up correctly?
What year is the LT1?

Im not sure how the painless harness is but with my speartech i had to keep all the power an fan wiring from my old harness.

iroc1793

iTrader: (2)

honestly i did not check any of the other sensors, i just checked the connector going into the opti spark, and checked the wire labled fuel pump test wire.

if i test the power to other sensors what should i be looking for a couple volts depending what the sensor should read for the provided conditions?

it is a 94 lt1, im not saying i hvae the power hooked up 100%, im asking here, all i know is that the engine turns over.

BCdawg57

iTrader: (1)

The engine is turning over because you have a cable directly on the battery to the starter. And as you said above, you have the pink ignition wire hooked up so the car knows you are trying to start the car. What we dont know is if the rest of your harness has power. Did you have to splice into a big (10 ga maybe) red wire from the c100?

www.shbox.com has some skematics and tests you can try. Your icm should have power when you have the key on, 12 volts i believe. As well as the maf and some others. If none of the pins on your harness connectors for those sensors have 12 volts then you have a problem with your power supply.

iroc1793

iTrader: (2)

correct i knew that was why the car was attempting to start, and ill agree i dont believe i have power to the rest of the harness, on the painless harness i didnt see a wire that was labeled to splice into the c100, i ran two red wires out of the C100 connector that according to the write up needed constant 12v, so i wired them to the battery for the constant 12v.

when i got the painless harness, i had two red wires labled B+ starter, so they are wired there, the ignition B+ fuse block which i was told i could splice into the pink wire under the dash, then fuel pump wire, two black wires labled grounds, and then a tach wire.

iroc1793

iTrader: (2)

So ive been reading and looking at diagrams on all data here at school, and i should be able to back pin into the B15 and B31 cavities on the connector into the pcm and see if im getting power to pcm. it should read 12v correct?

Also to check my grounds i should be able to back pin into A2, A18, and D1 for the pcm grounds. If i run one end of the multimeter from the positive side of the ternminal to the gounds i should get a reading of 12v correct?

im just wondering if im getting onto the right track with figuring out my problem, so i can atleast eliminate the power and grounds going into the pcm. Then if i have power/ground going to my pcm i can back pin at some of my sensors and see if im getting my 5v reference, and if im getting good reference voltage, and good power/ground to my pcm i should start looking where? at a faulty pcm?

BCdawg57

iTrader: (1)

First i would be happy with any voltage. Im not sure the exact numbers for the pcm. Before you start looking ahead make sure you are getting power to the pcm.

iroc1793

iTrader: (2)

correct just trying to figure out my line of diagnosis though, just trying to make sure im having the right train of thought

BCdawg57

iTrader: (1)

I'm not a wiring guru but I'd say you are on the right track. Post this on camaroz28.com there are a ton of knowledgable (sp?) people as far as lt1 there

drptop70ss

iTrader: (26)

what year PCM? How does the painless harness deal with VATS? Is it programmed out and a VATS simulator in place?

iroc1793

iTrader: (2)

I got a mail order tune from madz28. my engine is a 94, and i had the vats tuned out when i filled out the online order for my tune. i thought that if the vats was still on it would run for 3 secs and then shut off anyways, not just disable fuel and spark all together?

the painless harness has a vats bypass box on it.

drptop70ss

iTrader: (26)

depends on the year, I know the 93 with the resistor removed from the key will not even turn over.
If you do not have a signal from the opti to the PCM when cranking you will not have spark or injector pulse, but you should still have the fuel pump cycle on when you first turn on the key and get fuel pressure. Does that work? Do you have power at the PCM? Do you have an SES light so you can see if it turns on with key on?

iroc1793

iTrader: (2)

Im not 100% sure im getting power to my pcm. i dont have power to my fuel pump, i checked at my test lead, and had nothing, i connected a wire to the one i spliced into for my fuel pump, and ran the wire right to my battery and it worked, thats why im not 100% sure im getting power to my pcm, and if i am getting power to my pcm, and nothing is happening, then i think my pcm is messed up.

the painless harness comes with an aldl connector and light, i honestly didnt even think to look to see if the light was coming on, it should stay on with the KOEO correct? and if it doesnt even come on then im getting no power to my pcm?

drptop70ss

iTrader: (26)

SES should turn on with key on engine off.

iroc1793

iTrader: (2)

Thanks, im at school 4 hrs away from my car, so im going to send the message to my dad, feel kinda dumb for not even thinking of that to be the quick check to see if im getting power to my pcm.

iroc1793

iTrader: (2)

Since im 4 hrs away from my car, and couldnt get home this past weekend, i had my dad test my maf and a few other sensors to see if they were getting a 5 volt reference. i have not been able to talk to him yet, but from what i was told from my mom was that there was no reference voltage present at the sensors. So this would leave me to believe that i am having a problem with my pcm not getting power, or my pcm being screwed up. i will talk to my dad later and see excatly what he tested but i just want to check with you guys and see if im going on the right track with the no power to pcm, or if im getting power to my pcm then the pcm is screwed up. I have another pcm that i got with my donor car that isnt tuned for my setup, but should i have him try throwing that pcm inplace of my other one, and see if anything changes?

BCdawg57

iTrader: (1)

All this testing was with the key on right? I'm not sure if your PCM would be the problem but if you have another one it would be dumb not to try it. If that doesn't fix your problem, then the problem is most definatley in your wiring.

Have you checked your fuses?

Klortho

The PCM should have a 12v constant, and a 12v switched. The Injectors will have TWO 12v switched, and the ignition will have one 12v switched.

The fuel pump relay will have one wire coming from the PCM, one wire coming from a 12v constant, one wire going to the pump and one wire going to ground.

I used the original 4th gen harness with the fusebox, so all I ended up doing is wiring up the fusebox to the respective places under the dash in the stock 3rd gen harness, injector fuse in the 4th gen box to the injector fuse in the 3rd gen harness, ignition fuse in the 4th gen box to the ignition fuse in the 3rd gen harness etc etc. Sounds like alot of work I did, but I can put a TPI motor back in the car and just plug everything up, didn't cut a single wire, I cut up an old V6 harness to get the ends to use to splice everything in.

iroc1793

iTrader: (2)

Yes i have checked my fuses, i can double check when i get home this weekend, i have another pcm i will try to see if it makes any difference, its hard being at school, and having my dad check things for me, and not seeing the actualy results myself.

iroc1793

iTrader: (2)

I will have to check for the pcm power wires you have listed, the painless harness had two wires going to constant 12v source at the starter. But i do not recall having one going to constant 12v source, and another being a switched power wire. It had a wire labled B+ ignition, could this be that wire you are talking about?

agian thanks for all the help guys. really wanna get this thing running

iroc1793

iTrader: (2)

Here is another thought, i should be able to check and make sure i spliced into the correct ignition wire by testing at my splice for volatage with the KOEO. correct?

also just to clarify that i didnt miss it in the diagrams, but there was no B+ ignition wire on the C100 bulkhead connector was there?

im just trying to get my thoughts out to you guys who have done this before.

thanks again

iroc1793

iTrader: (2)

i believe that i have spliced into the wrong ignition wire. can someone confirm which wire they spliced into, and please dont just say a pink and black wire or an orange wire, there alot of those under the dash, i believe i need to go into the pink and black wire on the back of the fuse block that is labled for the fuse ENG CNL

Klortho

No, there is actually a fuse marked IGN and then for the injectors, one marked INJ1 and one marked INJ2, both wires should be pink/black

iroc1793

iTrader: (2)

i tried to fuse i mentioned above and got my fuel pump to run, so then i still need a ignition one? do you have a pic?

Klortho

IGN is for the ignition, the other two are for the injectors, there are two different wires that come out of the PCM for injector banks, one for the even cylinders, one for the odd cylinders

The fuel pump is controlled by the PCM also, there should be one constant hot (orange) and then one from the PCM, one ground and then one that goes to the fuel pump. I used the original fuel pump wire that hooked to the distro block on the side of the radiator support.

iroc1793

iTrader: (2)

okay so if im understanding correctly, i need to run my dist wire to the fuse that is labled IGN. and then my fuel pump hsould still run, and i will have power to everything on the harness?

sorry for the dumb questions, i thought i had an understanding of what i needed to do, but sometimes i feel a bit in over my head

iroc1793

iTrader: (2)

okay so im looking at my fuse box, found the two spots labled IGN with arrows pointing to them, now on the back side there is one spot that has a pink with black trace on, and the one below it has pink with black trace and then a gray wire also whcih should i be splicing into

andrew69_04

iTrader: (1)

im not a big lt1 guy, but if the lt1 ecm is somewhat similar to an ls1 ecm, the computer does not control the positive wires. ECM's control grounds only so dont expect to get power wires comming out of your ecm (this is assuming an lt1 is like an ls1 ecm)(internally, not externally)

Klortho

On my original LT1 harness, which is pretty much the same as the painless without any ends on it, there should be a wire that comes from the PCM, should be white that goes to one side of the fuel pump relay. There should be an orange wire that goes to a constant hot for the PCM, there should also be a pink/black that goes to a switched hot for the PCM. There should be a pink/black that goes to a switched source for the ignition, and two pink/black that goto the injectors.

That is saying that Painless maintained the same color coding as the stock harness.....I have found out from reading that the painless harness isn't that painless to install, that's why I kept the original LT1 engine harness.

iroc1793

iTrader: (2)

when i tried splicing into the two wires on the fuse block that are labled ign, i got the fuel pump to run for two seconds then shut off(key on engine off). Then i tested to see if i was getting voltage at the ign coil, and i used my multi meter to test for 12v, and got nothing with the key on engine off. is it possible for you to tell me which wire excatly you spliced into on the fuse box labled ign. i have two there, one is a pink wire with a thin black tracer, and then another pink wire with a thinck black tracer.

any help is appreciated guys.
thanks alot!

iroc1793

iTrader: (2)

so ive decided to undo all the zip ties and electrical tape to trace the harness for any cut wires or anything and ive found a pink wire that is all frayed on the end and you can tell it was into a connection of some kind at some point, and it runs down to the ignition coil. so im pretty sure this solves my no spark problem, however, now i need to figure out where this wire came from...any thoughts?

Klortho

I wish I could, I spliced mine in at the ends of the harness where the original plugs were at where it went through the passenger side wheelwell where the original TPI harness plugged in, I just found the one that turned off when I pulled the fuse and wired it in there. One side of the fuse connector should always have power on it when you pull the fuse out, the side that the power goes out when you pull the fuse is the side to splice into.

iroc1793

iTrader: (2)

alright thanks, this project has been nothing but a nightmare...thoguht all the wiring would have been simple cuz a fellow board member was supposed to make me one, and well he screwed me over big time, so i bought this used painless harness and even that is working right...kinda regret starting this project

Klortho

Well, I hate to say buy another harness, but it might be worth getting a regular 4th gen harness.

iroc1793

iTrader: (2)

ive already got a 4th gen harness laying around. i dont really wanna start this all over again. i think ill try giving painless a call tomorrow and see if i cant find out where that wire goes...

iroc1793

iTrader: (2)

just found this on the onlnine painless pdf file...

The pink wire labeled coil power needs to be connected to the wire that powered the coil on the original engine.

so which wire would this be on my car? 1985 camaro 305 tpi. do i just fine the wire on my old harness and then connect it accordingly to my car?

Klortho

That would be the one connected to the IGN fuse.

iroc1793

iTrader: (2)

Okay so just connect the ign b+ wire to the ign fuse, and then connect the other coil wire to the other ign fuse on the fuse block and i should be all set as far as that goes?

iroc1793

iTrader: (2)

So i checked all my powers/grounds to my pcm:

A2-pcm ground 13v
A18-pcm ground 12.8v
B15-battery feed 12.9v
B31-battery feed 12.9v
C32-pcm ground 13v
D1- pcm ground 12.9v

im getting a solid 12.6 volts to my coil, and i tested my igntion module with a test light and it is getting power aswell, im getting power down to the opti. im going to borrow a coil and ign module from my friend i hope tomorrow to rule those out, so im thinking maybe i screwed something up when i put my cam in? is it possible to have the opti 180 off like with a normal hei distributer?

chevyowner02

iTrader: (3)

A 94 is splined drive so that you can put it on the cam gear IIRC it should have a couple splines missing and in the cam gear. So unless you took a hammer to I dont think you could have it out 180. Or unless you did not have #1 at TDC.
Found a pic so you can see
http://shbox.com/1/93-94_opti.jpg

BCdawg57

iTrader: (1)

Is your fuel pump priming? Have you checked to see if you are getting spark? I would verify those before you go swaping parts. See if your plugs smell like gas.

iroc1793

iTrader: (2)

I tested for spark yesterday still no spark, the fuel pump comes on and primes for two seconds as it should, thats why i went to test to see if pcm was getting power and grounds, and then tested to make sure i was getting power down to the opti and to the coil/ign module.