I bought a 85 iroc with a 305 with tpi. I drove it in to the garage and did the engine swap. Now it turns over with fuel pressure and spark but the injectors will not fire. Also i dont get the fuel pump purge when i turn the key. Also no test lights come on. Not sure where to go or to test.
I also tried another ecm with no prevale. Can anyone help me? I'd like to keep the tpi but if i cant figure it out i guess it will get a carb. Thanks for ur time

 

Did you change the distributor? Do you have spark?

 

A strange thing: you have fuel pressure but no fuel pump prime. That could point to a bad fuel pump relay. But you still have fuel pressure because once you start cranking and build up oil pressure, the FPOP (Fuel Pump Oil Pressure) switch will turn the fuel pump on anyway.

Do you have power to the injectors? Test the pink/black wire on the injectors for 12V with key on. You can also spray carb cleaner into the intake before starting and see if it fires up. That would confirm that your injectors are not firing.

We have plenty of troubleshooting articles, feel free to check them out: http://www.austinthirdgen.org/index.php?pid=2

Let us know what you find.
Lou

P.S.: No matter what you do, please don't turn time back 100 years and put a carb on the engine, that would be the worst mistake.

 

I have chevked for 12v at injectors and there is power. I also sprayed starting fluid down intake and it fired. I have noticed all of a sudden my tach has pegged its self out and when cranking it comes down instead of going up. I also bypassed the fuel pump oil pressure switch to turn on the pump.

 

i also found that the two orange wires coming off the ecm are not getting power with key on. If i put power to one of them as soon as i turn the key the pump primes but it still wont start. What tells the injectors to fire? I also noticed the fuel pump relay and peg tail are pretty bad. Im getting a new peg tail and relay today to see if anything changes. Does the fuel pump/ oil pressure switch need to be in or can i just jumpper it? Again thanks for you're time

 

Also what would cause the bulb check not to work when you first turn the key on?

 

Did you put the grounds back on the rear of the passenger head? That's where the ECM gets it's ground. You might want to take another look back there.

 

i did doudle check that. i have a wiring dig for the ecm and it has all its grounds and power except for the 2 orange wires which when i supply power and turn the key the pump does prime. but still does not fire. i also have no 12v signal to the fuel pump relay. could it be a ignition switch?

 

To recap:
- fuel pump works, just not the relay
- fuel pressure is good
- you have power at the injectors (fuse is good and ignition switch is good)
- you have spark and timing is good (engine fires with fuel in the intake)

Which orange wires on the ECM did you mean? ECM pin numbers would help us identify them, probably the best way.
Also, don't put 12V on random wires (even if they are orange), you might cause irrepairable damage to the ECM or other circuits, not something you'd want. So be careful.

Is the BIG connector on the distributor hooked up?

Do you have a laptop that you can connect to the ECM (via the ALDL connector) to see what the ECM is reading? Primarily whether it is detecting any engine rotation. Because if not, there will be no fuel injected.

Two possible sources of your problem I can think of right now:
a) VATS - which is a little unlikely since you can crank (VATS disables the starter as well)
b) ECM doesn't see engine rotation (tach pulses from the distributor)

I'll think about it some more, I can't think on the spot right now.

Lou

 

Yes the big connector is hooked up. the pin numbers are b1 and c13. not sure if its the same being i pulled the diag off of all data. My diag tells me that these wires should have 12v with key on. I also did find a fusable link above the heater box. One end goes to a looks to be a plug in. The link goes in on the bottom side of it and 2 red wires come out on each side. there is power going to them both. The link is wrapped in with another wire that is grounded to the pass side wheel well. Both of them run to the front of the car and i can't figure out where they are suppose to go.

 

The orange wire on pin B1 definitely should have 12V at ALL TIMES, not only with the key on.
Check the inline fuse by the battery. It's in a single fuse holder, bolted to the fenderwell. It powers the fuel pump and ECM. Without it, the ECM won't run. THAT might be your actual problem. I actually HOPE it is!

What do you mean by "heater box"? What you're describing sounds like the main fusible link for the fans and fuel pump. Which might be another possible source of your problem.

Lou

 

I did have to replace that fuse when i first had this problem. Is that wire suppose to run to the back of the alt? I also hooked up that fusable link wire and now intermitenly the brake lite flashes as i turn over the motor.

Also would my problems explain why my tach is pegged out and only moves when the battery is running out of juice as im turning over? It starts jumping but its jumping backwards. Its wierd. I spent hours on this thing last night and ended up with a buzz and me pulling wire looms to trace wires. Ha ha.

And I also know that the injectors are working as far as when i disconnet all of them i ran a test light to the harness which i get 12v and this i thought was wierd but if i plug one in and then test the other term i can hear the injector firing. Not sure if that helps at all but.

Im pretty sure its the ecm not fully turning on or what ever it is that tells the ecm that the motor is turning over. But then again not a whole lot of expierence with fuel injection. If this was a carb it be done. lol

Again thanks for all of this help.

 

Hmm, let's take this systematically, step by step, that'll make it easier.
- Check for power on the orange wire by the single inline fuse on the fenderwell.
- Check for power on the orange wire on the fuel pump relay.
- Check for power on pin B1 on the ECM.
They all should have uninterrupted power at all times. Wiggling the fusible link harness should not interrupt the power.
Also, turning the key on should not affect the power presence on those wires, check that as well.

Lou

 

Ok so i did figure out that there are two orange wires up front with the same plug. i switched them around and i am now getting power to ecm on b1. The pump is priming but Its still not firing.

Also maybe this is causing it. When the pump primes as soon as it shuts off my pressure plumits. When it is on i can hear it running thru the fuel rail but almost sounds like its not filling all the way if you know what i mean. i also put a light on the injectors to test for the ground and its a very weak signal it seams to me.

Also i still get no ses light. I pulled the instrument cluster and the bulb is good. but the tach is still reading 7000rpm no matter what.

 

ok so i got everything working but in the process of starting it the power wire got so hot that it melted the terminal right out of the battery. it would turn over strong and once in awhile it would hesitate and sound like it wanted to fire. so now im stuck again.

 

well lou. want to say thanks for the help. got it started and it sounds beautiful. so again thank you

 

Morning, sorry, I was very busy yesterday and didn't get a chance to reply. But I see you sorted it out.
Tell us, what was it? I'm sure it will help others in the future if they have the same problem.

Lou

 

IT was a stuip little thing. Up front by the battery was 2 orange wires. one runs to the fan relay ond one runs to the ecm. they were swapped so that the ecm was connected to the fan relay. lol switched them and now it runs great. I do have to turn over quite a few time and feather the gas to get it started but i belive i have a bad fuel regulator. other then that sound great. now im dealing with the exhaust but thats a simple bring to the exhaust shop and have them make it. So again thanks for pointing out the orange wire up front lou. I probably would have been looking for that all day.n The funny thing is i brought it to tpis in chaska here and they couldnt figure that out and took 200 dollors of mine. they dont know **** is what i found out. i will never recommend them to any one.

 

Great, glad you found it!
Thanks a lot for posting the result, it will help others in the future when they find your thread.

Glad to see another 3rdgen back on the road.
Lou