KingsHustleLA

On Sunday I Started My Car In The Morning To Turn It Around To Swap Out The Rear End And It Fired Right Up. Later On That Evening When The Rear End Was Bolted On I Went To Start It Up So I Could Drive It Around The Block & It Would Die Within 3 Seconds After Turning Over. Last Month It Was Acting Up, I Changed The Fuel Filter, Fuel Pump, MSD Blaster Ignition Coil & It Ended Up Being My Ignition Module, I Changed That Got It Running And Its Been A Month But Now It's Acting Up Again, The Ignition Module Was Tested Today & Is Fine, My Fuel Pump Works Because The Damn Thing Stays On Unless I Disconnect My Battery So Thats Still Working, I Heard It Can Be The Sensor For The Cam Or Another Sensor That Has To Do With The Engine, Would Anyone Be Able To Give Me Ideas That Would Help Me Troubleshoot This Problem On Why My Car Dies Within 3 Seconds After Starting It? Thanks.

ASE doc

Sounds like a VATS issue. That's often how they fail. The engine will start but stall right away without the fuel enable signal. A VATS problem should set a code 45 in the ECM. Another thing to check is EST(electronic spark timing). The ignition module is in bypass mode below 400rpm. It provides spark to start the car on its own. Once the engine reaches 400rpm, the ECM applies 5v to the tan/blk wire of the 4 pin connector to activate EST. In EST mode, the ECM provides primary ignition pulses over the white wire of the 4 pin connector. EST is designed to automatically default to failsafe mode should there be a problem in the system. The car should stall once then restart and run in failsafe mode. The ECM will set code 42.

Read codes in the ECM to see what might be happening. Try starting the engine with the tan/blk wire timing connector unplugged. If it runs this way, you have an EST problem, probably an open in the white wire, or a bad ign module. They test good all the time and still don't work.

Correction: code 46 is security system problem, code 45 is rich exhaust

KingsHustleLA

Hmm I See, I Also Connect & Disconnect My Battery Everytime Im Done Driving Because My Fuel Pump Stays On After I Turn My car Off So I Need To Disconnect The Battery To Stop & Im Sure Disconnecting & Re Connecting It All The Time For A Month Could've Done Something To cause That Problem Would That Seem About Right? So To Check The VATS Do I take The Computer Out & Take It To A Place Where They Check Car Computers? And Also That Tan/Black Wire, Would It Be By The Distributor Or Where Would That be Located? Thanks For Your Reply By The Way, I Really Appreciate It.

ASE doc

There is no way to check an ECM out of the vehicle. You need to get your fuel pump control working properly. Ive known ricers who remove their ECM everytime they leave their car for fear someone will steal it. Resetting your ECM erases all of its adaptive memory. This means that each time your start your car, the ECM has to start from scratch learning fuel trims and idle management. You also need to educate yourself on atleast the basics of diagnosing and repairing your EFI GM car. I'll help you where I can but it's much easier for me to help you if you have a basic working knowledge of the subject. Having said that.......

To read codes, insert a paper clip shorting terminals A&B of the ALDL connector. The Assembly Line Diagnostic Link is located below the steering wheel under the dash. It's a 12 pin connector and pins A&B are in the top row, far right. Once you have inserted the paper clip, turn the key on, do not start the car, and watch the Check Engine light flash. It will come on for one second then turn off. Then it will flash codes. The first code is code 12. It will always flash this code when placed in diagnostic mode. Code 12 means that the ECM is running diagnostics and that the engine is not running(no crank pluses received). Code 12 will repeat 3 times, then any actual failure codes will flash. Record these codes and post them for me.

The tan/blk wire comes from the distributor and goes into the ECM harness. There is a "timing connector" in this wire, it breaks out of the main harness along the firewall, probably right on top of the power brake booster. This is the connector I want you to disconnect and try starting the car. Another thing to check is your Oil Pressure Fuel Cutoff switch. First verify that the engine is full of oil and making oil pressure. Then verify that the oil pressure switch isn't leaking oil into the connector area. This is a sign of a failed switch. This switch closes at 5psi and allowes the fuel pump to run as well as injector signal. If it's not closing, the injectors will shut down.

Knowing now that you disconnect the battery everytime you park the car, it's possible that your ECM has simply lost it's basic programming. Try forcing the car to run by feathering the throttle. See if it won't recover. Of course this is somewhat useless if you continue to reset the ECM everytime you park the car.

Search for wiring diagrams to your fuel pump control circuit and see if you can't properly repair it. By proper repair I mean replacing parts with new and making all wiring connections permanent and solid so that you don't create problems for yourself. Better yet, buy a Helms Publishing Factory Shop manual for your car. Read this manual cover to cover and you'll know more about your 3rd gen f-body than half the guys on here.

KingsHustleLA

Oh I See, yeah I've Been Disconnecting That Battery For Almost A Month. I Unplugged All 3 Relays At The Same Time & The Fuel Pump Still Kept Going, Shouldn't One Of Those Relays Been My Fuel Pump Relay And Shut Off The Fuel Pump When It Was Unplugged? Also My Oil Pressure Sensor Is Broke & Leaking Oil From There, Im Sure My Oil Is Really Low By Now Because I Haven't Added Oil Since Sunday. And The Oil Pressure Would Be Dropped Right Now So I need To Go Buy A New Oil Pressure Sensor & Do An Oil Change.

OK I Just Did The Paper Clip Thing With The ALDL Connector & Put One End In A And The Other In B When I Turned The Key The Check Engine Light Would Blink Once, Then Twice, Repeated That 3 Times And Then It Blinked 4 Times & 6 Times And It Reapeated It 3 Times Than Go Back To Blinking Once & Twice 3 Times And Then 4 & 6 Three Times. I Didnt See Any Number 12 Anywhere & I Didnt See It Blink 12 Times And After That I Turned The Key To The Off Position & Turned It To The On Position And It Did The Exact Same Thing.


The Black/Tan Wire I Couldn't Find From The Forewall Yet, I Think I remember A Black/Tan Wire That Plugged Into My Ignition Module When I Changed It Last Month, Would That Be The Same Black/Tan Wire You Said To Unplug?

So I Would Need Someone To Feather The Throttle As Soon As The Car Started? If I Tried Starting The Car And Gassing It All It Does Is Die Still & Pushing The Gas Seems To Have No Effect. So The ECM Could Be Ruined Or What Would I Need To Do? I Also Unplugged The ECM Earlier And Took Off The 1st Piece To Smell Inside To See If I Selt Anything Burnt & It Smelled Fine.

Also My Ignition Key Has A Chip Could The Chip Have Gone Bad In My Key? The Chip # Is 7. Where I use To Work We Made Car Keyes And You Stuck the Key Into The Machine & It Told You What Number The Chip Was, Could I Take My Key And Have It Put In That same Machine That reads The Number & Maybe If The Chip Is Messed Up It Wouldn't Be Able To read What Number The Key Is & I Can Maybe Find Out That way??

Oh Ok So I Would Need To Check The Diagram For My Fuel Pump Control Circuit & replace Old Wires That Look Bad Or Old With New Wires Or What? And Ok For Sure I Will Get One Of Those And Read It From Cover To Cover

ASE doc

Okay, now I see what happened to your fuel pump control. The Oil pressure sender that's leaking is what causes your fuel pump to run on, replace it. The one fash, two flashes is code 12. the 4 flashes, six flashes is code 46 which I believe is a VATS code. Your key doesn't have a "chip" in it. A chip is a semiconductor made of silicon. Your key has a resistor pellet. The #7 you refer to is its resistor value. The resistor pellet doesn't fail. It's just a chunk of resistor material and unless it's physically broken, it really cant fail. The contacts that the resistor pellet connects to when you insert it into the ignition can fail or stick so that they don't make good conact. Often just wiggling the key in the cylinder will unstick them.

ASE doc

46 is VATS system problem. This is why your car is stalling. Check the fuses in the in dash fuse panel. One is the security fuse. Make sure its good. Your starter enable relay must be bypassed or the car wouldn't be starting at all. Unless the VATS module has just died and isn't sending the fuel enable signal to the ECM. Your best bet would be a VATS bypass. On your age of car, the VATS system is a liability with a high failure rate. If you want anti theft, install a good alarm. A bypass module is available on line that replaces the VATS module, providing the fuel enable signal to the ECM. These modules run about $25. The bypass module doesn't control the start enable relay so you have to permanently bypass it, if it's not already bypassed.

Beware of cheap resistor packs being sold as bypass modules. The resistors only replace the resistor pellet and key lock switch. They will not solve your problem. When you do go to install the bypass module, you'll need good wirng diagrams for your car. I won't try to tell you what wires go where because I don't have access to wiring diagrams for the 90 model year here at home.

ASE doc

Do a Google search for "VATS bypass" you'll find links to buy the module and installation instructions. Buy the Helms manual and read it so you know your car.

KingsHustleLA

Oh Alright, I Just Got Done Checking All My Fuses And Changing Them And It Didn't Start, It Would Be One Of The Red, yellow, Clear Or Blue Colored 10, 15, 20, 25 amp fuses Right? Yeah I Heard That My Car Had A Chip In It But Im Not Sure If That Included Passing The VATS Also? Hmm So If Anything Would It Just Be Better To Take My Car To A Professional And Have Them Install The Chip Since It Has To Do With Something Like That?

Oh Ok I'll Google It Right Now Thanks!

ASE doc

A professional may have an easier time pinpointing the cause of your trouble. I just hope that you find somone who actually knows these early vehicles and soesn't just guess and trow parts at it.

KingsHustleLA

Oh Alright I See, Would This Chip Work?

http://tpiparts.net/inc/sdetail/657


Or Would You Happen To Have A Link Of Something Better Or Includes Performance?

ASE doc

I suppose that would work. I'm more familiar with the bypass modules that simply replace the VATS module. I'm concerned though that your problem hasn't been properly diagnosed. I've given you a possible cause but before you replace anything, you really need to verify that this is the problem. By connecting a scan tool, you could see if the fuel enable signal is getting to the ECM. You could also look at other possible causes in datastream. You could use a DVOM to measure voltage on the Dk Blue wire from the VATS module to the ECM to verify the signal.

camarosrock1989

iTrader: (1)

Hey Doc if your ever in Az, I could use your help! I love it when a man knows his stuff. I am a women but really like working on my car. I just redid my headliner, watched about 3-4 video's. and was not as easy as it looked. But I have one more headliner to make it right. lolol
I have a throttle body injected motor, I think it is a 350. I can't get it to start, used a little starter fluid and started> sounded good but shuts right down. Motor is sitting in a 91 RS. I really would like to see how good it is, to decide if i want to drop in my 89. Really just wanted to say thanks for your knowledge and you help.

camarosrock1989

iTrader: (1)

I just went online to try and find on of those Manuals and they are not cheap. Close to a few hundred bucks on ebay. ouch

SiCkRs

iTrader: (6)

Your problem might be your fuel pump thats what it was on mine and had the same problem as you have

ASE doc

That's right. To check fuel pump, listen with your ear to the filler neck with the fuel cap off while a helper turns the key on, then tries to start the car. When the key is turned on, the pump should run for two seconds then shut off as the ECM waits to see crank pulses showing that the engine is being cranked, when it reactivates the pump for as long as the engine is turning. Once oil pressure goes above 10psi, the oil pressure fuel cutoff switch also provides power to the pump and you should hear the pump for a second after the engine stops turning until oil pressure falls below 10 psi. If you do not hear the pump running, check the fuse by the battery.

If the engine is an implant, you may have to search for the fuse as it may not be mounted as it should be, but it should be there unless the wiring was hacked up. If the fuse is good, use a test light under the car, just in front of and above the fuel tank there is a connector coming from the body to the tank unit. Disconnect this connector and look for power at the tan or gray wire when the pump should be running as described above. If you get power there, verify ground on the larger black wire. If power and ground are good, replace fuel pump.

KingsHustleLA

Oh I See Hmm Do You Think If I Used The Resistors On The Wires Under The Dash & See If It Starts & If It Does Then That Will Be My Problem & from There I Can Drive It So A Professional? Or Would It Not Work Or There's More To It Than That??

camarosrock1989 - Yeah If You Hear The Fuel Pump Work Than Here's Something Else You Can Try. I Had That Problem Last Month, My Car usually Didn't Crank Over And If It Did It Would Run For A Few Seconds And Start To Stall Out And Die & I Changed My Fuel Filter, Fuel Pump, Coil & It Ended Up Being My ~Ignition Control Module~ If Your 350 Is Tuned Port Injection The Ignition Control Module Will Be Under Your Distributor Cap With 3 Plus In It, You Can Take It Out In 15 Minutes If That & If There Is An Autozone Near You Some Locations Can Test It For Free & Tell You If Its Bad Or Good, That's The Cheapest & Easiest Place To Start. Also You Can Disconnect The Fuel Lines From Your Engine, Put Them In A Bucket Or Have Someone Hold Them Over A Cup, Than Turn The Key In Your Ignition To On, But Dont Start It And See If Gas Comes Out Of One Of The Lines, One Is Your Return Line So Gas Only Needs To Come Out Of 1. But I Would Say The 1st Place To Start Should Be The Ignition Control Module Under The Distributor Cap

KingsHustleLA

And Dont Worry About That Fuel Pump Rodolfo We'll Take Care Of That By Friday

SiCkRs

iTrader: (6)

Oh alright for sure hopefully the tranny works on it if not then t56 on that bitch lol

KingsHustleLA

**** It! Sounds Like A Plan LoL

ASE doc

KingsHustleLA, Your probelm could also be the ignition module. I mentioned EST in post #2, the ignition moduel is part of that. One way to test for this is to put a spark tester on a plug wire and watch to see if the spark dies before the engine dies. Also, to verify whether VATS is your problem or not, put a noid light on one injector connector and see if injector pulse drops out before the engine dies. I don't generally recommend these tests because it can be hard to be sure of your results, but it's something to look at. The reason I finally cued on VATS is because of code 46.

pjammer

I moved mine to work on the tilt column and got the same thing. Starts n dies. my oil pressure switch was leaking, replaced and now my fuel pump wont stop running. I put a guage on the fuel system and it holds 42-45 psi.Also did the control mod. fuel filter. I get no codes.
Next i'll pull the fuel lines and check for flow.
Then i'll check to make sure the injectors are pulsing.once i know i'm getting fuel it's on to see if the spark dies b-4 the motor.
If you come @ it from a dif direction, maybe we can meet in the middle @ a solution. good luck, I'll keep you informed.

pjammer

I pulled the fuel lines and def. have flow in excess of 1\2 pint in 15 secs.
I have spark @ the coil and plugs. It's difficult to say what stops first, motor or spark but i have good spark until it dies.
It sure seems my injectors aren't firing. If i spray starter fluid in the intake, it runs.
I saw another thread that refers to code 56 as starter relay enabled but no VATs signal to ecm. Even running w/ st. fluid, it still has no codes.
I guess i gotta drop the ecm and make sure it's getting a signal from the VATS module and sending a signal to the injectors.
That may take a while, i'm trying to do all this w/ a torn-up back.