Ok here is the story.... 1989 WS6 formula with the 5.0TBI.
I just bought the car, it had been sitting in a garage for 3 years, it is completely stock, down to paper air filter and cover over the idle screw. I changed the fuel filter and pumped the tank empty at the filter and refilled the tank with premium. I let that sit over night and pumped it out and refilled again with a fresh filter.

The car starts for a second or two and then dies out, if i quickly pump the gas it will stay running a bit but then die out.

I changed plugs,wires,cap,rotor, rebuilt the TBI, new filters and gaskets,o-rings etc.
I checked fuel flow both at the filter and at the TBI and there is a strong flow of fuel.

Another, maybe related problem is that the car won't turn over with the key, so i have a switch wired to the starter relay, both the battery and starter are new, I'm thinking it is a fusible link somewhere.

Anyway what would cause the engine to fire right up for a second and then jsut die? I tried spraying carb cleaning while cranking the engine over and it runs a little longer, leading me to beleive it is a fuel problem even though the injectors seem to be spraying? The only thing I can think of is that the fuel pump is getting weak and even though it has great flow, it cannot build enough pressure. I will buy the fuel pressure gauge and try it out.
Any ideas?

 

Well of the 3 things you need to run (air, fuel, and spark), it sounds like youre getting all 3. Just something is "off" or it wouldnt cut out.

is it throwing any codes? If the SES light is on, jump the A and B terminals on the ALDL port.

Is the IAC/TPS set properly? MAKE SURE THE IAC PLUG IS CLEAN/CLEAN CONNECTION

Is the MAF (you are MAF, right) good? Good connection, etc?

All vacuum lines are on? NO leaks?

Timing is good? The outer balancer ring hasnt slipped?

 

VATS???

 

Is the battery good? If its been sitting that long, it might be a dud. Try running the engine off someone else's known-to-be-good battery and see what happens.

Your alt. might not be making enough power too. You can have that tested at just about any auto parts place.

 

No SES codes, i scanned with a data link also.
The IAC is 100% clean, i rebuilt the whole TBI unit. the TPS is non adjustable, no slots. There is no MAF it is a TBI car.

 

Same thing happened to me! my 88 form. TBI would start and die several times. Turns out after I scratched most of the hair off the top of my head I went and bought a fuel pressure tester and it was only putting out 7lbs of pressure! A new electric in tank fuel pump fixed the problem! It should be putting out 9 to 13lbs!
If it turns out to be your problem, keep the money and fix your car! The info is free!! But, there is a MAP.

 

If the battery is actually starting the car I would not suspect that just yet.

However I had this very same problem back when my car was a 305 TBI.

I changed every sensor, replaced every tune-up part...I was stumped. Finally one day my fuel pump died completely. Replaced that and it ran perfect.

When I had mine it would start right up perfectly and idle for a second and then get really choppy and die. Sometimes I could keep it revved up and finally it would idle on its own.

I wouldn't rely on "seeing plenty of gas" because I don't think you could actually tell anything by that. I would get a fuel pressure gauge and check the actual line pressure. It should be up towards 14psi or so. I bet its either your injectors or more than likely the pump itself.

 

It has a BRAND new battery, and the alt puts out plenty of volts. The car turns over very quickly and seems to charge ok, but the engine won't stay running long enough to really check. Regardless there is plenty of juice to run it.

 

Actually I am pretty sure it is either the fuel pump or VATS. But I was told VATS would not let the injectors cycle at all? If that is the case the VATS is not the issue.

The fuel pressure will be checked tomorrow.

 

i STILL HAVEN'T FIGURED OUT THE QUOTE thing yet, but he's right on the fuel spray thing. Mine still had a fuel spray cone that I could see after I got it to idle. Didn't make any diff. at idle, still had pressure problem that only the pressure tester could find!

 

I'd do like some of the others said then, and check the fuel pressure. Air is rarely the problem, and if the batt/alt are good, you likely have a good spark as well.

Whats your timing set at btw?

 

Seeing how stock the rest of the car is, and knowing the previous owner(the original owner) I'd say the timing was stock. I can't check it however due to the not starting issue.

 

well, being at idle the fuel consumtion is minimal, you might check the MAP sensor, make sure the vacume line for it is in good shape.

 

MAP sensor in a TBI car?

 

I second the VATS idea, but check the fuel pressure just the same

 

How can I check VATS? Would it allow the car to start for a moment then die?

The tech article on bypassing VATS seems like the next thing to try, does it work ok?

 

the best way to test the vats that I've heard of is, goto wal mart or somthing and have them cut a copy of your key, then try to start your car and see if it does the same thing. if it does that could more than likely mean the vats. the reason a key from wal mart or somthing won't work is because it dosen't have the resistor in the key. good luck

 

How about an ignition module that fires on module mode but not in run or ECM mode. Hmmmm..........

 

That sounds like a fuel pump to me. I had a Fiero that sat for about 2 years pull that same **** with me. The gas had actually turned in the tank though and it smelled sweet. I replaced the tank and the pump with a new GM unit, and viola, the thing ran like a top. I doubt the VATS is the problem since it starts and you can keep it running (although not for long) if you pump the **** out of it. I don't even think the MAP would cause it to aact like it is. You could try a little gas (or ether, just don't turn the car into a crack baby) in a spray bottle and do a little "Manual Port Injection" to see if it will run or not. If it wont run with the "I.V." it could have something FUBAR in the ignition system. My vote though, goes back to the fuel pump.

 

Where is the MAP sensor on a TBI car? Is it located on the Firewall? I can't remember seeing one.

 

Top of the firewall on the passenger side. It has a vacuum line attached to it and a two wire connector. The bolts holding it on go through the lip where the firewall is welded together. It controls fuel delivery by reading vacuum and supplys more or less according to engin demand and other variables read by the computer.

 

After the Fuel Pressure check tonight this is next to try out.

 

You can have the module tested at advance autoparts, autozone ect.

I have heard the tests aren't very accurate though. But if you suppect its wrong I would go buy the module and try it. If it doesn't help just take it back to advance and tell them you didn't use it. They will give you money back...trust me I work there. Managers will take back damn near anything.

 

I second the notion to check your feed line fuel pressure. Your pump can be shot even when you still see feul and what appears to be a normal cone shape spray pattern. Some of these pumps crap out yet maintain 6 or 7 PSI which is enough to make you go crazy thinking that the car is getting enough fuel when in fact it is not.

 

When VATS went out in my car it wouldn't even turn over. The security light (IIRC) just flashed, no cranking whatso ever. I'm thinking its fuel related

 

If he has a switch wired to the starter relay to start the car, then it sounds like he has a problem with VATS. Just a thought!!!!!!!!!

 

Does anyone know if his fuel pump is even being energized upon start up? Me thinketh I would look to wiring. Hmmmmm.........

 

Yes the fuel pump def turns on, its audible. Also I pumped out the whole tank using the pump,(in test mode using the ALDL connector).

The injectors def seem to fire, I have no TBI experience however so I dont know if the fuel flow is weak,ok or what.

More Info coming tongiht.

 

I'm ready to beam down Scotty! ENERGIZE!!! VADER would love this one!

 

I had the same problem n did a whole list of things...turns out it was the fuel pressure regulator / fuel meter (whatever you want to call it) that needed replacement

 

With some help, use a timing light to view the injector spray pattern. Since it won't stay on long, may have to do the I.V. method or "look fast".
At least this does not cost anything.
Keep us updated.

 

Fix this first and i'll bet your ten bucks that your other problems go away.

 

I wonder why the Vats would quit after sitting 3yrs? Who's to say it didn't quit 3yrs earlier (might be one of the reasons it was parked). I'm betting 20 it's the pump gone bad sitting 3yrs! Doubt it was submerged either. That might have helped, but sitting all that time dry didn't. Do I hear 30?

 

OK I checked the fuel pressure, it was about 6 psi. Swapped in a new pump fairly quickly, a 350TPI version. Fuel pressure is now 12-14 with the key on and cranking.

The car still will not start with the Key. I checked every fusible link I could find, and every relay. All looked good. All cables are pretty clean, no corrosion. Next thought is to bypass VATS and see if that helps, and to swap out the ignition switch and key cylinder from a known good car. I checked the key and the resistor value was about 6 ohms, does this sound right?

Does anybody know which pins on the auto shifter module to check to make sure the neutral safety switch is working ok?

The fuel is now not spraying at all, It seems to be a Injector signal problem which leads me to believe the VATS. So far fuel pump,ignition and all mechanical problems have been eliminated which leaves electrical and injection.

Please help me before a carb gets slapped on this thing,heh.

 

Hello MHaskell,

Simple check for the VATS system. Look under the dash for two white or yellow wires coming down the steering column. If white, they will have an orange wrap on them. If yellow, they will have a black wrap on them. They will connect to a harness with a black/white wire and a purple/yellow wire, disconnect this harness. Take a multimeter set to OHM's and measure the resistance value of the pellet in the key. Now put the key in the igniton lock cylinder (leave key in the OFF position) and measure the keys resistance value using the connector on the two white or yellow wires. If the value is the same, your problem is elsewhere. If it is different, then you probably need a new lock cylinder and key.

 

Thanks Trickster, I'll try that soon.

This is really getting crazy, at least the car has gotten a full tune up.

 

Ever considered checking the ecm to make sure it is good still? I have seen a couple cars with the same problem and it ended up being a bad ecm.

 

Other than getting a second ECM how can I check? I have a datalink cable, would that show it by sensor values? The interesting thing is that the SES never comes on, and only shows a code 12 when scanned.

 

Forgot to mention that I had this issue with my car as well when I had the L69 with CCQJet still as well. I checked everything out. Ended up just buying a new ecm from Autozone in the middle of the night and swapped the chip over. Solved the problem completely. There was no SES light at all.

I have no idea how you could test it. The only thing you could really do I think is to get a new ecm. Swap the chip and try it. If it doesn't work, take the part back. There is a core charge though if I recall. Someone else on the boards may know of a way to actually test the ecm you have.

 

I found the VATS connector under the dash and unplugged it, the car is acting exactly the same as before! WTF. So i guess it is a VATS issue even tho the wires read the 6,000 ohm resistance, the same as the key shows. I am going to bypass it now(I'm in the garage) and see what happens.

 

Mike, just thought here. Since you have a switch connected to the starter relay to start the car. Have you checked to see how it is wired at the starter solenid. Is the starter enable relay still in the car or does it just have the wires for that switch you mentioned. Look at that schematic I sent you and check the wiring. If you got a good reading using that test I mentioned, then the problem is not in the ignition lock. Have you looked at the ignition switch on the steering column under the dash? Just a thought!!!!!!!!

 

I wired the starter relay switch just like the paper you sent me said to. The car will now crank using the key. I'm not sure what I have to fix to get it to start without the starter relay jumped however.

It still fires right up perfectly then just dies after a few seconds.

If I pump the gas pedal it will stay running, but not very well.

Fuel pump and filter are new, it gets great pressure and flow now. The injectors fire nicely for a few seconds then the signal to open them just stops.

I even tried a passkey box and column from another car, I have no idea what to do now.

 

Distributor pickup coil or distributor module. The ECM needs to see reference pulses from the distributor to fire the injectors. Without distributor reference pulses (DRPs) the injectors will not fire.

Best bet is to get an entire distributor from a running vehicle and just swap it in. Then it is either that or isn't.

RBob.

 

mh, what town do you live in. If your in the south shore, PM me and I'll see if I can't swing by and take a peek at least.

 

I just got my camaro so i am just learning how to work on them, i had a 73 ranchero with a 351 Clevland before. Well there is a lot to learn on this.

I am replying becuase i dont knwo if i can help but i have a funny story that kind of relates to this: I have a freind who has been off and on with his ( now ex) for 2 years. She was a freak! in the middle of the nigt she would come into his room and just start punching him in the face while he was sleeping. SHe would bite him while he was sleeping FOR NO REASON. Well one day he came home from work and saw his glass headboard on his bed shattered, his sliding closet doors with mirrors on them shattered all over hte floor. Well he said, that was that. He took all of her stuff out of his house and put it on the roof of her car. Well he also grabbed a pair of plyers and went up right next to the fuel tank and crimped the fuel line until it was as smooth as a pancake. It was almost impossible to see it. Lets just say, she will be paying a mechanic a lot of money to find that kink. Also, she needs a place to live.

Anyway, this subject brought that story to mind. SO i will ask, have you checked to make sure your fuel line is not bent or kinked anywhere? If anything, i hope you get a laugh out of my friens 2 years of missery, lol.

 

It runs! Swapped the key cylinder and passkey module from a donor car. Everything runs much better now, due to all the new parts hehe. More later, i'm going for a ride.

 

ok well why dont you check your firing order...check to make sure its right.

 

Its right, it has been the whole time.


I forgot that the VATS had a 3 or 4 minute lockout once it was tried with a invalid key. Once I swapped over boxes and took a break, it started right up and runs mint now. Granted the 305 TBI is pretty slow, but it runs very nicely.

 

All that parts swapping and you should have started with the known problem.

Something to be said for testing.:lala:

 

Yeah lol, and you thought it was the ignition module and then a wiring problem. Sounds like a "Known" problem.


Trickster thank you so much for the help.