first time posting something cut me some slack if its a little funny or "off"

1974 Caprice 400 with 86 camaro(89 prom) TPI with MSD 6al
i have a 86 tpi setup with the 89 prom and the sonovabitch once again wont start. initially the car was running slightly lean on acceleration but pretty solid then the coil pickup in the dist went bad and left me stranded on a rainy day. fixed that ran solid once again and the alternator went leaving me stranded again. fixed that and somewere along the way the smog pump lines to the exhaust manifold that were plugged on O2 sensor side opened up and the car ran a pretty lean(i think stuck in open loop) for about a week but had no prob starting. started burning my own proms and left the car siting for 5 days and for the first time in my possession the car seen snow now it cranks but wont start and is in limp home mode

THINGS IVE TRIED AND KNOW
-reburning the prom with the ANZA.bin from tunerpro
-shooting it with starter fluid very little noticable change but i should retry i dont think i did it fast enough
-fuel pump turns on with the key in on position for a few seconds
-car barely coughs im pretty sure im getting spark
-the limp home mode on my memcal was made for the 305 so it wont run my 400 its run before in limp home mode but just had trouble idling and ran real lean
-brand NEW fuel filter, air filter, wires, plugs, cap, rotor, and ignition coil just for tune up
-parts replaced for problematic reasons are fuel pump, tps, ignition module and magnetic pickup coil
-exhaust manifold holes have been plugged
-bench tested and cleaned injectors a month ago
-datamaster would not connect to the ecm thru the aldl for **** but ive never used datamaster or datalogged b4
-if i pull the prom or the neg bat terminal and reconnect wen i turn the key in the on position it will flash once then stay on indicating it running from the prom, then after i crank it and until i pull the battery terminal again it wont flash and just stay on indicating its in limp home mode
-code 12 is all im getting
-VATS has been turned off
UPDATE:
-good compression above 150 on all cylinders
-a few pins on the computer look to be a problem mostly d12 and b1
-perfect spark
-when pulling plugs for compression test i noticed they were soaked in fuel
-injectors resistance 15.5-15.8(perfect)
-injectors tested with test light and they flashed very quickly with key in start position i guessing that means there good.

by 11 tonight ill be 100% sure on the spark and wether or not the starting fluid will help at all. im definitally not getting enough fuel/pressure or a steady amount of either. im kinda leaning towards a bad ecm but i dont know how to test and im not a parts buyer.

ive read somewhere that two terminals need to be switched on a 89 aldl from a 86 harness. i dont even really know if its a 86 underdash harness so its a mystery underdash harness, that may be my datalogging problem

 

just tested spark, good and gave it a heluva lota fluid and didnt change much. im thinking compression some advice would be nice

 

Assuming compression is good and you've got spark that leaves fuel. You mentioned replacing the fuel pump but have you checked the pressure with a guage? If so what is it? What about the regulator? How about the injectors themselves? You said you checked and cleaned them but are you sure they're getting power on the motor? Any chance you may have shorted out one of the injector connections and blew the fuse? Since you say it stopped runnning after you burned your first prom that may be the problem. Do you have the original prom chip or a known good one you can put back in and try?

 

i dont have a pressure guage but i guess im getting one. the fuses to the inj are good and the coil pickup is brand new so if the computers good im pretty sure im getting power at the injectors but i dont have a noid light to test if there at autozone and cheap i guess i gotta get one of those also.

the original prom was a eeprom that the burn 2 programmer couldn't burn. i didnt know this tried and might of damaged the original bin but after the original bin on the new eeprom wouldnt run the car i tried burning the ANZA.bin and still same thing barely coughing no start. i tried putting the original prom in. no good same thing. im thinking if i can figure out why its in limp home mode and get it to run off the prom i think the car will start i just dont know why it is in limp home mode.

30 minutes from now ill have the compression posted

 

160-8 7-153
155-6 5-155
150-4 3-153
151-2 1-153

looks pretty good to me tell me if im wrong. I noticed every plug was soaked in fuel a few fouled black. before when i checked for spark i checked at the coil (i got a external msd blaster) im guessin i must not be getting spark at the plugs or my timing is way outa whack.

the possibilities are shortening im thinking by the end of the day the car will at least idle but this doesnt explain why the comp wont connect to datamaster and doesnt explain why the car is in limp home mode?!?!?!?

if there is anyone thats reading this that has used datamaster to datalog if you could break down the whole process for me it would be appreciated or tell me why im in limp home mode or exacly what is limp home mode? because that might have something to do with me not being able to connect.

 

you can use a test light on the injector connecters and check for spark at the plugs.

 

im getting fuel the plugs were wet when i pulled them. just pulled a plug hooked it up to the plug wire and let it sit on the body to ground and the plug sparked fine but the bitch wont run

spark air gas compression i got all 4 the car wont idle this is starting to **** me off

 

if you have all 3 things and good fuel pressure and good spark my guess would be timing and are all plugs wet? id use a test light on all the injector connecters just to make sure they all are getting power and firing.

 

and make sure u have a chip in currently that you know it ran off of.

 

the original bin might be corrupted on the original chip, im not sure it wont run on either chip. and yeah all plugs were wet im bout to go outside and test the inj but im pretty sure there firing.

 

after you test them id find a known good chip and go from there

 

just tested the resistance on the injectors and the volts on the wire and i think i may have a problem. the resistance comes in at 15.5-15.8 which from my knowlege is perfect. the wires tho came in at full volts with the key in on posistion not ignition on both sides of the connector?! im pretty sure there not supposed to be open without the car running not only that but one side is a ground so only one of the 2 wires should have 12 volts not both?

has anyone seen this? tpi flowchart points to a bad ecm?

 

one of the wires should flash power during cranking and running and again if the chip is messed up it could cause alot of problems with your injectors.

 

found ANOTHER problem which may be the reason for the limp mode. i pulled the 2 connectors to the computer for the hell of it and noticed alot of that blue stuff that forms on battery terminals and creates resistance. pin d12 MAF burnoff had alot and had rusted and snapped off inside the connector. i pulled it out with some pliers and now since theres no way to get it back in to the computer im going to jump it and see what happens

where would i get a working prom to test on it? if i connect it to tuner rt and read the calibration theres no problem all the info comes up. no currupt file message.

 

Once spark plugs get fuel soaked they aren't going to fire properly, often not even with starting fluid.
Try a set of dry plugs and it might start up. An alternative is to sandblast them, then cook the tips dry with a propane torch for about 2 minutes each.

Limp home mode is most often triggered by an open connection, - loose wire or missing/bad sensor. The mystery harness could possibly be the culprit.

 

pin d12 (MAF burnoff relay) on the computer snapped off. this could be the reason for limp home mode right?

 

you mentioned 86 tpi setup. is the wiring also for the 86 tpi? and are you using an 86 ECM or an 89 ECM? 86 was a Mass Airflow system and the 89 is a Speed Density system. you'll probably have a short somewhere if you're not running corresponing computers and wiring... also look into what 305sbc said above about the plugs.

 

89 is maf with cold start enrichment in the tune like i said it used to run but isnt now. the plugs i cant keep them from getting wet because there stuck open, and as soon as the fuel pump kicks on there going to soak the plugs. im pretty sure its a bad ecm does anyone know where i can get 1 for a price better than 80 at autozone?

 

you seem to be stuck on the injectors being stuck open all the time, because as you say both wires had full positive voltage? this wouldn't complete the circuit for the injectors to open, you need power and ground, as for power being on both sides, this may indeed be true, one side will have power from a fused point for power the other will be coming from the ecu until the signal is commanded to ground to open the injector. Once plugs are flooded they are very hard to get to fire until they are dried.

From your story I'm gathering that the engine ran until you tried to reprogram and you found corrosion at the ecu connectors (never a good thing to find), that corrosion could be down in the wiring or may have gotten into the ecu itself. All of your ecu sensor inputs are based on exact voltage readings, corrosion adds resistance witch is like adding a load on the circuit = a voltage drop to the input signal, whats this all mean? Garbage in = Garbage out.

 

now that you say that about the injectors it does make sense. ill hook the multimeter in between the 2 terminals tommorow and see if it flashes or holds solid or maybe doesnt turn on at all. but i do understand the corrosion problem so i really have no other option but the grab the 80 and blow it on a new ecm. how do i keep the corrosion from happening again? im not a cheap guy but i really dont got money to blow on parts.

 

just tested inj with a test light in between both terminals. they flashed VERY fast. im not sure how fast there supposed to flash ive never tested them b4 but it was pretty fast. im guessing there good.

i also noticed on the computer that another pin had rusted up but hadnt snapped off yet d12 broke off the other pin that is a little corroded and rusty at the base is b1 which according to chevythunder is battery 12V there is a few more that have the blue stuff but d12 snapped and b1 is pretty rusty.

i obviously need a new ecm but i dont want this to happen to my new one anyone know why this happened or why this happens?

 

Did you check the fuse for the aldl?
IIRC , but I could be just mistaken but I think I had the connect to ecm problem and had to replace a fuse. I'll look up an old thread I have and see if I can find it. IIRC some other member told me about it.
Best of luck with the problem though.

 

The injectors get 12v whenever the key is turned forward in "run" position.
The injector driver in the ECM pulses the ground signal to the injectors.
You will see a noid light flashing as you crank the engine.

It's not exactly normal for an ECM to corrode, so yours must have seen some weather.
On the harness plug you can use some Silicone spray, axle grease, or the lube of your choice to protect from corrosion and make the plug engage/disengage easier.

I would start with a new ECM and go from there.
When you get the new ECM installed and some fresh spark plugs, I would concentrate on getting a datalogger to connect to the ECM before trying much else. That should let you know if there are any important "opens" on your harness or bad sensors.

If you have been flooding the engine for a while, there may be excess fuel contamination in the oil, so once it's running an oil change may be a good idea.

 

305sbc i have my whole harness running through my passenger window with the window closed as much as possible. it seems very likely that water could have run down the wires from the window and since the ecm is on the floor the water would have ran straight into the plug since its the lowest possible point.

I used a test light to test the injector with the motor cranking and it flashed very fast so im guessing the pulse is good. the plugs ill probly clean them off and reuse them and the oil im changing im gonna seafoam it. i gotta change the oil after i seafoam soo ill post my results when i get a new ECM. ONLY 60 BUCKS AT ADVANCE mean deal i think i payed more for mine used and its rebuilt with a warranty.

 

new computer still no good