I just swapped a TBI engine/tranny from one '89 car to the other. The donor was a running, driving car when I pulled the drivetrain (almost 3 years ago - worlds slowest engine swap).

First distributor guts fell apart (magnet/bearing under the cap), so replaced the distributor. Now I am getting spark. I've got an inline tester, and it is lighting up, so that issue is resolved.

Car still wont start. No fuel. Here's the deal. Unplug negative battery terminal, let it sit 30 seconds, then screw it back in. When I turn key, I get a quick spray of fuel at the TBI, maybe a fraction of a second. it has a nice cone-shape, so thats good. But thats it. I will not see another spray unless I unplug the batter again, and wait another 30 seconds.

I'm not seeing a "security" light on the dash, so I'm thinking it's not VATS. Doesn't VATS also disable spark?

I'm leaning towards a bad ECM.

Thoughts? Suggestions?

 

There should be no fuel spray unless the engine is cranking.

The injectors spray when the ECM grounds the circuit. The injectors are powered with key-on. About the only thing that could cause the injectors to spray is an ECM grounding the injector wires, or a spot of bad insulation on the wires accidentally touching ground. "Accidentally" wouldn't be that predictable, I'm guessing.

 

It only sprays the first half-second that I am turning the key, with the engine cranking. Then every other time I turn the key, engine cranks, but no spray.

 

Possibly a failed ignition module. Your first post didn't say anything about you turning the key far enough to crank.

 

I ran to a local boneyard this morning, and grabbed an ECM off a '88 TBI car that was there. I'll plug it in, tomorrow morning, and see what happens. I'm really thinking this might be a VATS issue. I'm curious what will happen with an '88 ECM, being that VATS didn't really start on lower model birds till 1989. What will happen with a non-VATS ECM being plugged into a VATS car?

 

The 88 ecm will work fine you might want to bypass the starter enable relate if your going to bypass the vats.
a tbi truck ecm 747 would even work in a pinch. But the engine calibration could be much better.

 

I found the starter enable relay. It looks like someone has already beat me to it. They have snipped the thin, dark green wire (that is supposed to go to the passkey decoder module) and simply grounded it to the body. There is also a thin yellow wire, a thick yellow wire and a thick green wire. I unhooked the relay, and connected the thick yellow, to the thick green, but car will not even crank like that.

 

So here is the starter enable relay. You can see that someone cut the green wire, and permanently grounded it (they have connected the green to a short red wire, leading to the grounding screw in the body):


Is this the reason the car is cranking? Everything I've read about VATS says when the security light is on, the injectors don't spray, and the car won't crank. But my car is cranking

Is there anywhere else I should be looking for ******* engineering?

I'm planning on just doing the resistor fix, but I'm still not even convinced this is the issue.

 

This bypass would allow the engine to crank. One quick way to see if it’s the vats is remove the prom from the ecm and see if it fires up. Another way to test the passkey system is to measure voltage at the ecm blue wire at pin b6.

 

Thanks Tuned, for the quick response. I just ran out, pulled the prom, and she fired on the second crank. First time this engine has ran in almost 3 years. Whoo hoo!
So if I go ahead and do the resistor band-aid, should I also re-connect that green wire at the relay? Can you think of any other hacks in that area that might have been utilized?

 

I would leave the relay alone but check what’s under the electrical tape.
No other hacks I can think of.

 

Okay, I'm at wits end. WTF am I missing? It should not be this difficult

Measured the key. 2.97:


I've got a resistor reading 2.99. Perfect:


Unplugged the VATS wire (you can see the orange-wrapped wire hanging over on the right). Cut the connector off the end, used alligator clips to temporarily hold the 2.99 resistor in place:


When I try to start, same issue. I still get the initial spray, but then, nothing:

 

 

 

Your finger 'n' thumb are in contact with the conductive probes of the ohmmeter. Your fingers are creating a parallel circuit that drives down the resistance the meter is measuring.

ALSO

Did you "zero" the meter by touching the probes together with nothing in between? There may be a "zero" procedure, or you may just have to subtract the meter reading with the probes together from the meter readings when you're actually testing something. I drove myself nuts one afternoon trying to get a reading on some low-ohm project, but I forgot that the meter leads had about 0.2 ohms resistance, which screwed-up my reading by that amount.

AND

Do you have a decimal error? 2.97 KOhms would be right in line with #9 on the chart above. I can't read the range your meter is set to.

 

Tuned and Schurkey, thank you so much for your help. I **FINALLY** got it. Turns out, I have a mutt car. I already knew that, but now everybody else does, too.
I took the list from Tuned above, and verified that I had each of the 15 resistors. I put them in order. And I started at the top, one by one, waiting 5 minutes between tests.

Turns out, I should have started from the bottom. It took me 15 tries, before #15 finally worked.

Now, the real fun begins.

 

Hello, im having the same problem my car almost starts up the first time i turned key than after that it will crank but no attempt to start,

What wires do i test, that the chart 1-15 the guy said had fix his car
Any help please i been trying to start for a few days already going onto 3 weeks

 

Do you have a TPI or TBI? If TBI, take the air cleaner off, and verify that you get that one quick spray of fuel that I show in the above video, then no more fuel.

My car was an oddity (or maybe not so odd) in that it's a theft recovery, and nothing matched. You can see in post #8 above, where the starter enable relay has been cut. This relay is located behind the front driver side kick panel. You can see that the green wire has been cut, and run to a ground (green-to-red wire, going to body). I think this is what is allowing my car to crank, but of course I was not getting fuel. Everything I've read said VATS will not crank when it doesn't read the correct resistance.

The VATS wire is under the dash, in a bright orange sheath. Can't miss it, two wires with a connector. There are dozens of videos on youtube, showing how to install the resistor override. You can buy the resistors on eBay, all 15 of them in a kit, for under $4 shipped. In my case, the key was resistor 6, but the VATS in the car was #15. I had to go one resistor at a time, to see which resistor worked.

Now that I have mine all sorted out, I have purchased two GM keys that have the correct resistance (again, on eBay), and I plan on removing the VATS resistor override that I installed.

 

Car has been running fine for the last few months. I've put 0 miles on it, but started it, driven it up the long driveway, that sort of thing.
So last weekend, I washed it, and put it into the garage. Yesterday, I went to start it, and **NOTHING**

Battery is charged, interior light comes on. I turn the key, there is no --click--click--click-- sound. There is no fuel spray. Nothing. Security light comes on for 2 seconds, then goes off.

• I'm certain it's not VATS, as there is no spray, and the "security" light goes off
• I checked every single fuse, thinking something might have blown, including the one under the hood by the battery. Everything looks good
• I don't think it's the starter, because I'm not getting a clicking noise

Any thoughts?

 

What is the Open Circuit Voltage (OCV)?
What is the voltage when someone turns the key to "Crank"?

What is the voltage when you test the starter solenoid "S" terminal when someone turns the key to "Crank"?
What happens when you jump the "S" terminal to the battery cable?
What happens when you turn the key to "Crank", and then pull the shift lever from "Park" to "Neutral"?

You need power from the battery, through the bulkhead connector to the interior of the car, through the ignition switch, through the neutral-safety switch, maybe to a starter-enable relay. There'll be at least one fuse in the circuit, but there could be more, or a fusible link. Eventually, the power gets to the S terminal of the starter solenoid. No click, solenoid probably isn't getting power. No power, no cranking. No cranking, no fuel spray.

 

Sometimes, it's the little things. I was prepared to swap out the starter this morning, but started simple. Yanked an ignition relay off my parts car, and was going to swap it into the "good" Formula. Guess what? No relay in the good car. I assume the harness fell out of the relay, as the car was running last weekend. Anyway, popped the new relay on, and the car fired right up. Strange part, I can't find the old relay. Schurkey, thanks for the input, I do appreciate it.