When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Ok so I still havent got the 96 T/A to start. New battery tested good, new coil, new opti and hoses from petris, new nuetral safety switch, new fuel pump and filter, new starter, fresh oil and coolant. Parasitic draw is gone ( bad new optima ). So I decided to try to crank it. It turns over but wont fire. New plugs and wires too. I plugged obd2 scanner in and it failed to connect. Ive never had this issue. After an hour of youtube, it says I more than likely have a faulty sensor. So disconnecting them one by one until it connects to tell me which one is bad? Any other suggestions possible?
Do you have spark? Do you have 40+ PSI fuel pressure? Has the ICM been tested? When the starter is cranking the engine, does the tach needle move up a couple hundred RPM? Another post indicates you were looking at a used Hypertech Power Programmer. Did you buy it and use it?
Alarm problem yes, I had shimmy with key fob for it to work and I disarmed it, wiring, everything looks wired right as far as shboxs site, replaced purple wire from nuetral safety switch because there was visible burn mark. Getting fuel to Schrader valve, got gas on finger tip (there was none before fuel pump replaced). No fuel in vacuum line from regulator, but still have to go get the fuel injection test kit....and while Im at it rent a compression leak down kit. Fuses were good, but Ill check them again. I just got the spark tester (pic below) and negative positive test probe. (Excited for some reason.) The switch he installed was a manual fan switch it seems. (Signs of thermostat probe in radiator and wire from switch goes to nothing in that direction.) I took all wiring that was visable and not powered to anything out. (Sub wire to trunk and not even connected to fuse link or battery, led underglows i took off). Other than the spark, fuel psi, and compression tests and checking fuses again the only thing I could think of is a bad ecm (dont know if he had it tuned or if its stock) I have a new stock ecm in my storage (210 miles away from where I used to live) with my vin etc . already programmed. Trying to not make that trip if I dont have to and I have a 1 year return policy. If its the fuel regulator, thats fine Ill replace it. If its the ICM (which I put Standard brand on) Ill get a acdelco. If its a sensor I'll replace. If its compression related...It'll have to wait..which sucks. I dont think its the ignition switch, the failing symptoms of that described by shbox arent relative to my problems. Maybe a relay? How to test? Or possibly its the crank sensor? (I replaced that before new opti with Holstein brand from rockauto) Or map or maf sensor? (Thinking compression/air wise). Where is the bcm? Does a 96 have one? Thinking of all possibilities, if the aftermarket alarm and radio are somehow wired wrong would stop it from starting, but security light turns off and the red blinking light stops. Will vats bypass eliminate them being possibilities? If I had the money and time Id buy an oe wiring harnesses from front to back. Oh and after months of calling/texting- still no reply from the previous owner on whats all been done, and was it done professionally etc. Awesomeness. Lol. My first goal, get obd2 to work. If so that'll help. If I cant- possible bad ecm (got to take that drive).
the probe lights red for pos green for neg.
Start with the basics, one step at a time. Get organized.
Do you have spark at the plugs? All you need to do is pull a wire off a plug, hold the wire near the block while the engine is cranking, and look for a spark. Don't hold the wire with a bare hand. Having spark rules out the PCM, Opti, ICM and coil.
= = = = = = = = =
Which of these statements is correct:
- "new opti and hoses from petris" from rockauto)
- "new opti with Holstein brand"
= = = = = = = = = =
Do you have the required fuel pressure? You can't judge by pressing the core of the Schrader valve.
= = = = = = = = = =
Check the "CIGAR/ACCY " FUSE #11 IN THE PANEL ON THE END OF THE DASH.
= = = = = = = = = =
Describe what happens when you turn the key to "Start". Does the starter crank the engine rapidly? What is the voltage on the dash gauge when the starter is cranking the engine? Is there any sign of the plugs firing - some popping or backfiring? Does the tach move up pa couple hundred RPM?
= = = = = = = = = =
It is unlikely that a single sensor will prevent the engine from starting, other than the optical cam position sensor in the Opti. The crankshaft sensor is not used to run the engine, it is only there for misfire detection. If the MAF fails, the PCM defaults to speed-density.
= = = = = = = = =
1996 was the first year with a body control module (BCM). The BCM does control the PASS-Key (VATS) system and the factory alarm system (optional, RPO UA6 - does the Service Parts label indicate your car has UA6?). The BCM can be scanned with the correct scanner. It is located on the passenger side, behind dash, above the bottom of dash insulator/closeout panel.
= = = = = = = = = =
Here is a link to a free download of the 1996 factory service manual, courtesy of GaryDoug. It has info on the location of all the components, troubleshooting logic diagrams, etc.
Alarm problem yes, I had shimmy with key fob for it to work and I disarmed it if the aftermarket alarm and radio are somehow wired wrong would stop it from starting, but security light turns off and the red blinking light stops. .
yes if alarm is wired wrong that can prevent the car from starting.
I dont think it is, because it ran for about a month before it started having problems...When I ran obd 2 back then all it gave me was a misfire code, which I changed plugs and wires. Then it would stall randomly and start back up, thats when the real issues started. Changed coil with autozone coil and icm and it ran about a week. Then wouldnt start again. Bought a ac delco starter it ran about another week. Then bought a cheapo opti, it fried inside. Then found out filter/orfice thing was missing, so I bought a opti and vacuum lines and accel coil, new standard brand icm and new remy starter. Before attempting to start checked the optima battery I bought for it at the time and it was bad. So I got it replaced with another new one. And changed fuel pump because I couldnt hear it and one of the pins on the connector was fried. Replaced fuel filter also at that time. No I get gas at Schrader, but still have yet to check psi. New belt, alternator has been tested good, New safety switch with new purple power wire (had burn on wire that exposed copper). Think everything is good, it turns over but no start. I checked fuses, put all new in. So Im assuming spark, or possible injector, or compression.
Does that "Repair Report" indicate you got the OBD-2 scanner to connect, and you got P1351?
Is the dash photo there to indicate the tach movement when the starter is cranking the engine, and the voltage?
What is the picture of the fuse for? Is that fuse #11?
It would help if you told us the purpose of each attachment.
P1351 is for "Ignition Control Circuit High Voltage". This is the signal the PCM uses to tell the ignition control module (ICM) to fire the coil. It is the white wire that attaches to pin B of the ICM. Lack of signal often means there is a problem with the low resolution pulse signal from the Opti. Shoebox has a guide to verifying this circuit:
You need to use the code definitions specific to the LT1 engine, and not some generic description from the scanner. Download the factory service manual as I suggested. Look at Volume 2 of 2, Part 1 of 2, Page 6E-739. It tells you what can cause the code, specific to the LT1 engine. But do the Shoebox check first.
First picture is key in on position, not turning to start. That was before anything I changed out. Fuses are all new and in correct spot. Opti is brand new with vacuum lines from petris. So I went out to check spark....battery dead. I put it on charger and well lets just say this is the second brand new yellow top optima that is bad. Went from 5.4v to 6.1 then back to 5.4. Went took it back for a duralast agm. Its on trickle charger for the night. Hopefully thats the fix to my problem. I'll check tomorrow after I leave it on trickle charger tonight.
And yes I have the factory service manual, and thank you guys for not getting irritated with a f body newbie. I wish I could upload videos from my phone, but I'll update tomorrow.
If the photo of the dash was taken "key in on position, not turning to start.", why is the tachometer indicating ~600 RPM? It should read "0" if the engine is not running. Or do you mean the picture was taken with the engine running, with the key in the "run" position? Is that an old picture, before the new "won't start" problem cropped up?
One last try - did the scanner connect, and do you currently have P1351? Or is that some photo from the past, and why are you posting it?
Finally got a new battery (duralast platinum agm). Still no start, but cranks. New coil, new opti, new wires. Havent checked for spark yet my jack finally crapped on me. Havent ran fuel test, since pump and filter are new. I know I should because the fuel injection kit test kit is loanable and cheap...but the obd2 wont let scanner connect which leads me to think its the ecm or ignition control module. Also thinking the icm isnt to blame because the ecm should still be able to connect to obd2 right? Yes fuses are all good and new. Under the hood and on driver side. Anyone with similar issues let me know, or good advice. Oh and plugs are new. Acdelco double platinum (oe)
10-15-2020, 09:10 PM
