Need the brains of LTX

[Jerry93Z]

So far, I've dropped the tank, replaced the opti, replaced the plugs and wires, replaced the coil, replaced the ECM and charged the batt.

Today/tomorrow I am going to make sure the injectors are spraying and double check spark. I can smell fuel when she's trying to turn over though...she still will NOT start.

Any ideas or advice on where to start troubleshooting? The help is much appreciated.

[Fastbird]

Three things needed. Air, fuel, spark. That said, I'd venture to say spark if you're smelling fuel while cranking. Have you checked the obvious like the fuses? I ran around in circles one day for a simple blown fuse under the hood. If you don't have any luck by later today, I will paper some scans from my 93 service manual for the "cranks but will not run" diagnostic chart.

Rezound + Tapatalk = Me making posts

[Jerry93Z]

Yeah, I checked fuses, which brings two questions: there are two fuses under the hood that read "injector" I am not getting hot from either of them with key off, cranking, and accessory. Even after I replaced them. Fuse block partially dead? How do you check the large block-like fuses? There is no contact spot to check.

[Ryan Stout]

Check the ICM? Like fastbird says, sounds like a spark issue. Also check the opti harness. Is it throwing any codes?

[Jerry93Z]

Check the ICM? Like fastbird says, sounds like a spark issue. Also check the opti harness. Is it throwing any codes?

It's throwing a check engine but I do not have a reader.

[Fastbird]

If its a 93 like your username suggests, use a paperclip in the top row two right end spots on the aldl and flip the key on but DO NOT start the car. This is how to flash the codes on the 93's. The SES light will start flashing and the fans will come on. The first series will be Flash...pause......flash flash.....long pause.....repeat 2 more times. That's dtc 12 for diagnostic mode. Rest of the codes are flashed 3 x each. When done, it loops into dtc 12 until you key off. Get code....report back. :)

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[Jerry93Z]

Fastbird, that was a cool little trick. After dtc 12 got done. I got 4 flashes,pause, 6 flashes. Did that three times and then back to dtc 12. Soooo give me the bad news...

[Fastbird]

Interesting. Looks like your Pass-Key or "VATS" as it's commonly known is on the fritz. Check out the pics I attached from my service manual (these are OLD scans and low quality, but legible). Pay special attention to the first paragraph under "Test Description" on the 2nd page.
96159616

Now for the potential fix. Use this website: http://shbox.com/1/how_tos.html and read through items 25-27 on that page. It's about the VATS system, troubleshooting, and bypassing. I ended up doing the bypass mod to my car because it decided to die the 2nd time I tried to start the car after 3 years on jackstands. You can do the bypass WITHOUT cutting anything, simply add the proper ends to the resistor you get and slide them on to the pins for the harness instead of cut and splice in the resistor.

[Chris]

Hey Jerry, the flashes should be different lengths kinda like an sos code, so say 2 long and 2 short would be a dtc 22

[Jerry93Z]

Interesting. Looks like your Pass-Key or "VATS" as it's commonly known is on the fritz. Check out the pics I attached from my service manual (these are OLD scans and low quality, but legible). Pay special attention to the first paragraph under "Test Description" on the 2nd page.
96159616

Now for the potential fix. Use this website: http://shbox.com/1/how_tos.html and read through items 25-27 on that page. It's about the VATS system, troubleshooting, and bypassing. I ended up doing the bypass mod to my car because it decided to die the 2nd time I tried to start the car after 3 years on jackstands. You can do the bypass WITHOUT cutting anything, simply add the proper ends to the resistor you get and slide them on to the pins for the harness instead of cut and splice in the resistor.

I looked that up but my security light does not flash while trying to start...should I attempt the bypass anyway? Ooorr do you think that because this ECM is used and I didn't get it programmed to my VIN could be the problem? Since the bypass is most likely cheaper I would probably do that first.

[Jerry93Z]

Also, just lifted up the fuel rail, injectors are sputtering more than spraying. Looks like I need injectors. :(

[sinistr]

Also, just lifted up the fuel rail, injectors are sputtering more than spraying. Looks like I need injectors. :(

thats the vats disableing the injector pulse

fastbird is that from a 93 gm manuel (?) lol

[Fastbird]

Yes Will that's from a 93 service manual. For the op, the security light may or may not flash dependent on the failure. Do the bypass, it'll fix your car especially given its throwing that code.

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[Jerry93Z]

Yes Will that's from a 93 service manual. For the op, the security light may or may not flash dependent on the failure. Do the bypass, it'll fix your car especially given its throwing that code.

Rezound + Tapatalk = Me making posts

What wattage resistor do I need then? I have the Ohms.

[Fastbird]

What wattage resistor do I need then? I have the Ohms.

Use those links that I have you a few posts up. Showbox's website. He's got a chart with the correct resistor to use based on the ohms your pellet gave.

[Jerry93Z]

I'm sorry Fastbird, I'm not finding it.

[popo8]

#'s 25-27


Components:

Pellet in the ignition key (one of 15 different resistance values (http://shbox.com/1/4th_gen_tech2.html#pass_key))
Ignition key lock cylinder with sensing contacts allowing “reading” the resistance of the key pellet
Theft Deterrent Module (TDM) that monitors the system (this function is embedded in the BCM [Body Control Module] for 96-97 years). Modules are located under the RH side of the dashboard.
Theft Deterrent Relay (TDR) - relay that is wired in the path between the ignition switch and the starter.


http://shbox.com/1/4th_gen_tech2.html#pass_key

[Jerry93Z]

Ok guys I must be retarded, I'm just going to buy any 682 Ohm resistor because I'm not seeing wattage instruction anywhere.

[popo8]

What wattage resistor do I need then? I have the Ohms.

Did you click on the link I posted? I think your over complicating this. You stated you Ohm';d it right? What was the Ohm reading?

[Jerry93Z]

682 Ohms, pellet #3. I can buy a resistor for that Ohms but Everyone I call is telling me I need the wattage of the resistor as well. Resistors have a ohm and wattage.

[popo8]

682 Ohms, pellet #3. I can buy a resistor for that Ohms but Everyone I call is telling me I need the wattage of the resistor as well. Resistors have a ohm and wattage.

IDK that you do.... that will be a FASTBIRD required answer. VATS is TUNED OUT of my car...

[firebird_1995]

1/4 watt

[Jerry93Z]

Thank you, now I can try to hunt this baby down. Thank you again, guys. I apologize if that was a bit frustrating. But at this rate with all the help you guys are giving me I should just sign the title over to all of you. :)

[popo8]

....I should just sign the title over to all of you. :)

Deal!




And seriously, its no problem.... its what we do here.

[Jerry93Z]

Put the resistor in....no start. And there is an aftermarket alarm on here.

[Jerry93Z]

Okay, I've put the resistor in and I have power to the injectors now. :) buuuut still no start. :( I go to crank and the security light stays on constant. I can smell even more fuel than before AND its gurgling while turning. I have spark....fuel pressure??? Maybe? Also, I'm missing these relays.. I think they're relays: 9743

Will they cause a no start? This is extremely frustrating, I am not sure which direction to go?

[The SRZ]

Okay, I've put the resistor in and I have power to the injectors now. :) buuuut still no start. :( I go to crank and the security light stays on constant. I can smell even more fuel than before AND its gurgling while turning. I have spark....fuel pressure??? Maybe? Also, I'm missing these relays.. I think they're relays: 9743

Will they cause a no start? This is extremely frustrating, I am not sure which direction to go?
Check your fp for starters. Those aren't relays btw. It's just where you can tap into for additional stuff you may want to add and you are using that as a pwr source. Curious though, what did your pellet read off your key in terms of resistance/ohm reading. I'm in the same boat so to speak and my pellets are #12 w/ a 6040 reading. Don't know crap about resistors or how to make a resistor in that range and I have the multipack. Been youtubing it but that just something I haven't caught on to yet.

[Jerry93Z]

I will get a fuel pressure gage this week and test it. The injectors may be gummed up too though so I have to check that out as well. My key read a #3 so I bought the correct resistor, put it in and...nothing, still no power to the injectors. Then it dawned on me; my ECM is from another 93, so shot a text to the previous owner of the ECM-- got his pellet code and bought a resistor for that value. (#14) threw it in and it worked, no more dtc code 46 and power to the injectors.

As far as getting a resistor for that value...the tolerance on the pellets are so large that as long as the Ohms are some what nominal it will work. Shbox shows the nominal values of each pellet. I couldn't find the correct Ohm resistor for pellet 14 at any store. Go to bestbuy.com and search "resistor". They will have a kit of 15 resistors specifically for the vats system. They don't have singles so you'll have fourteen resistors that you will never use..

[The SRZ]

I will get a fuel pressure gage this week and test it. The injectors may be gummed up too though so I have to check that out as well. My key read a #3 so I bought the correct resistor, put it in and...nothing, still no power to the injectors. Then it dawned on me; my ECM is from another 93, so shot a text to the previous owner of the ECM-- got his pellet code and bought a resistor for that value. (#14) threw it in and it worked, no more dtc code 46 and power to the injectors.

As far as getting a resistor for that value...the tolerance on the pellets are so large that as long as the Ohms are some what nominal it will work. Shbox shows the nominal values of each pellet. I couldn't find the correct Ohm resistor for pellet 14 at any store. Go to bestbuy.com and search "resistor". They will have a kit of 15 resistors specifically for the vats system. They don't have singles so you'll have fourteen resistors that you will never use..

Damn, GM vats pack?! SUMMUHMUHBEYOTCH! I got two used 93 pcms coming in this wk as a matter of fact and would've never know this. LOL Thanks! I sure hope that's the fix.

If you're inj are gummed up, throw some seafoam or soak them in some and that'll clear em' out.