dec010974

iTrader: (1)

on my wire harness i have 6 leads from the fuse block. (2) go to the hot sources and (4) go to ignition sources. i connected (2) to batt. and (4) to igniton sources that get power when the key is turn on. also my starter is wired to the old wires that powered the 383 starter. my motor turns over but wil not stay crunk(idle). the company that sold me my harness, computer, tac mod and pedal states that the tac mod is what keeping the motor from running. they r sending me a new one that copatible with pedal next week. has anyone encounterd this situation?

ls1nova71

iTrader: (4)

Need a little more info, does it start, but won't stay running? Have you had the VATS deleted from the PCM? A bad tac module I don't think will keep it from idling, you just won't have any reaction at the throttle body. Also make sure you have the MAF hooked up, I've seen cars that won't stay running without them.

dec010974

iTrader: (1)

thanks for the reply ls1nova71. it does cranks and turns over as long as i turn in the key ignition. the motor sounds like its about to start. i had two DBW computers from the same company and they say the motor SHOULD start. both computers were sent back to the company and im wating for them to send back a new tac and computer. i started the motor with them on the phone. others say the crank sensor may need reprogramming. im almost at the end of my line. i sold my 383/700r4 combo last week and if i cant get it to work ill be building a 406/350 lockup tranny. as a last effort, i may try to carb the motor, but i have a 4l60e to worry about.

lamdenali

iTrader: (5)

I have the same problem but my car is Drive by Cable , try the 10 or 12 gauge wire ,connect it direct to battery then start the car it should run fine. make sure what ever crank wire you connect it to must be 12 volt, I connect mines to a wire that is not constant 12 volt and it wont start.

good luck

dec010974

iTrader: (1)

im a bit confused about your answer. 10 or 12 guage wire, the connection should run from the 12 volt source/battery to what? crank? huh? spell it out in eglish lamdenali. im no mechanic. trust me.

ls1nova71

iTrader: (4)

I think what he is trying to say is make sure your power source to the LS harness has power when ever the key is on. Some have connected it to a wire that has power when cranking, but nothing in the run position. What did you use for that? It's easiest to use the old distrubutor/HEI wire to power the LS harness.

dec010974

iTrader: (1)

6 wires of power from fuse block. (2) go directly to the batt. (4) go directly to key on/ingition. i havent tested the for power while the motor is running. motor doesnt run. also these sources may loose power while cranking. like i said before, im new to mechanics. ive learned a lot to get the vehicle wired this far. but the motor act as though it wants to crank. may be ill need to contact the vendor for more input on wiring up this puppy. if the possibility of runnung 5.3/4l60e FI wont happen sone i may carb the motor an look for a 350 or 400 tranny (which ill price tonight) and go that route. its the easiest route for me and i can get it running myself and shordee will be back on the road.

gofastwclass

iTrader: (2)

...at least in my opinion - which isn't worth the pixels necessary to display it.

I assume this is an aftermarket harness with fuses... I will also assume ALL connectors are plugged in solid on the engine. If there are any even remote doubts check the entire engine.

There are two connections behind the intake, one is tall with one wire (oil pressure switch) and the other is short and points to the driver side (cam position). Another critical connection is the crank position sensor which is behind the starter. You will have to take the starter off to get to the crank position sensor because it needs to be plugged in as well. Oil pressure switch doesn't do anything it only runs a light on the dash, but without the cam and crank position sensors active you aren't doing anything more than spinning the engine. Behind the engine there is also a two wire connector for the knock sensors but the engine will start and run without them for quite a while. Depending on the pan you have a useless oil level switch may be built in the pan, but it isn't necessary either. Every other sensor you can see / get to from the top of the engine fairly easily.

Basig Gen III / IV wiring is as follows (GM colors, your harness may be slightly different)
Orange constant 12V+ (battery)
Pink 12V+ in start and run only - NOT the power to the coil in a distributor car since those are usually run through a ballast resistor and won't supply enough juice.
Black or Black with white stripe - ground. Make sure the engine is grounded to the frame, body AND battery.

Engine needs around 58+ PSI of fuel pressure at the rail to fire and run.

If those basics are not met you are not going anywhere.

dec010974

iTrader: (1)

im using an aftermarket harness. i will check all connection today especially crank and cam sensor. if i remember correctly, the cam sensor was pointed to the passenger side when i got from junk yard. basically i wired the motor. with the harness, while it out of the vehicle. vendor states the non starting motor is due to the wrong tac module. hopefully tac arrives today. any other thoughts would be appreciated. also my buddy checked it with his scanner and no codes were notated.

armour

what company did you get the tac module and dbw pedal from? I am looking for this as well.

dec010974

iTrader: (1)

ssp wiring(in arizona). i purchased dbw harness, tac module(they sent me the wrong one,so they say) ecm, footpedal, an maf sensors. wait to purchase to see if this puppy will crank. their tech is ify. wait til i get my motor running. i heard howell has a good rep. i you can go drive by cable.

dec010974

iTrader: (1)

hello to all. i recieved the new tac module and the puppy wont start. i guess i have to scan the ecm for codes. that 400 small block is looking better at this point. the saga ccontinues. always wanted a 400 small block.

lamdenali

iTrader: (5)

I feel the same way and almost drop my BBC back in ,then the Pink wire which is 10 or 12 gauge wire was only around 6 volt to it . I connect it direct to the battery and she fire right up