• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

740 No Pulse to Injectors, Has Spark

That’s what I’m saying, I don’t think you can install it backwards. Look at the back of the cam, the slots aren’t directly down the middle. They’re offset. I thought the same thing when trying to start this Regina car but I couldn’t install it 180 out. Check crank/cam timing.

I’m not 100% sure you can’t be 180 out, but either way it’s easy to time a head mounted car. All you need to do is make sure the little slot on the crank washer lines up with the line on the block. Then, make sure the dot on the cam gear lines up with the line on the timing cover. Don’t even need to touch the aux gear (though I do it anyway).

If the engine is mechanically in time, you can pull the dist cap and make sure the rotor is point to cylinder 1 at TDC. The rotor will be facing somewhat downwards to a contact point that leads to cylinder 1. Look at the inside of the dist cap and that will make more sense.

Here’s the crank washer.
TimingMarks5.gif


And cam
TimingMarks2.gif
 
Last edited:
As I suspected, the distributor was backwards. The drive dog was put on backwards, so with cylinder 1 at TDC, the rotor was on cylinder 4.
Managed to get that stupid pin out after banging on it for hours, and now the pickup for the hall sensor is bent. I have another one, but it's pretty crusty... and I have to drive that damn pin out AGAIN.

This car better run after all this...
 
Pop off the oil filler cap and see turn the engi e until the number one cam lobes are each pointed up about 45 degrees= number 1 TDC. Can't hurt to pull a plug and make sure piston is at the r
Top. Also camt hurt to check timing. And compression. Ok, now you're at number 1 known TDCcheck the rotor and make sure it's pointing to number 1 contact within the dist cap.

You smacked out the dowel on the dist at some point and took the key off!?

That's why I have the no start thread linked in my sig. We've been saying all along to run it on ether.
 
Oh you meant the little thing that slides into the back of the cams slot? I didn?t know it could be removed! Glad you found it.
Yup, there is a small pin in there. I had taken it apart to replace the hall sensor (which I really didn't even need to do).
Was the cam lining up with the TDC mark as well, or just the crank?
Both the cam and crank lined up with the timing marks, yes.
Pop off the oil filler cap and see turn the engi e until the number one cam lobes are each pointed up about 45 degrees= number 1 TDC. Can't hurt to pull a plug and make sure piston is at the r
Top. Also camt hurt to check timing. And compression. Ok, now you're at number 1 known TDCcheck the rotor and make sure it's pointing to number 1 contact within the dist cap.

You smacked out the dowel on the dist at some point and took the key off!?

That's why I have the no start thread linked in my sig. We've been saying all along to run it on ether.

I'll double check, but I see no reason the cam shouldn't be in the correct position. I pulled the #1 plug to make sure the piston was at TDC, and it was.

I did remove the key, see above. I just got done putting it all back together the right way. Ended up getting the pickup plate straight enough, and I went ahead and replaced the dizzy housing seal (which FCP forgot in that order) while I had it apart again.
Rain's coming down now, so in the morning I'll get it back together and at that point there is NO reason it should not run.
 
Don't be conservative with the brake cleaner/ether. Blast that down the throttle a few times and crank it by yourself from under the hood. Just turn the key to on and manually fire the starter with 12v applied to the solenoid terminal or wire using a jumper wire.
 
Don't be conservative with the brake cleaner/ether. Blast that down the throttle a few times and crank it by yourself from under the hood. Just turn the key to on and manually fire the starter with 12v applied to the solenoid terminal or wire using a jumper wire.
I should be able to get it going tomorrow. No reason it shouldn?t run now.
What order do you have the plug wires plugged into the distributor cap? head mount is 4312 left to right ( I think) block mount is 1342

Yup, they were correct, 4312. It shows the numbers on the cap.
 
Okay, got the dizzy on and it runs on ether! I couldn't get it started by jumping the fuel relay terminals, though. I want to pull the fuse panel up in a little bit and inspect it once again for corrosion or loose wires.
I highly doubt the problem is the relay itself, but I guess anything's possible.
 
You for sure jumped all 3 connectors in the relay panel, right? If you only jumped the pump, your RSR will not receive power. You already knew this from page 1 of this thread though, but just reminding you in case.

Remove the RSR and jump 12v straight from the battery to the wire that runs to the injectors. Or you can bridge the red wire (constant 12v) to the injector wire. Doing it straight from the battery eliminates the possibility of faulty wiring on that side of the wiring.

Anway, I?ve found RSRs to be extremely annoying and finicky even when they appear to be clicking and functioning properly.

Not entirely sure if your wires will be the same color, but they should. On a turbo car this relay is on the drivers side I believe, but you?ll need to check.
24969d1507153497-please-help-1990-740-radio-suppression-relay-wiring-relay1323592diagram.jpg
 
Yeah, I tried that previously and it made no difference. I for sure have a full 12 volts at the injectors, so I don't think the RSR is a problem.

I checked the connections at the fuel system relay for the same readings as their corresponding pins at LH, and everything lined up, so the problem has to be within the relay.
Apparently, LH pin 21 is supposed to show battery voltage with the key on, and mine only shows 1.72 volts, but it shows 12V with it off. I haven't tried it with the jumper, but I will.
LH pin 21 is connected to 86/1 at the fuel system relay, and that shows the same reading with the relay in place.

I also noticed FSR terminal 85 shows 12.3V with the key on, while LH pin 17 shows 11.94V. Is that a difference to worry about? That voltage drop would lie within the wire. Or at the boost over pressure switch or the right a-post connector.
 
Pulled the rail and injectors and the injectors are NOT spraying at all. When I removed the number 1 injector from the rail, plenty of fuel came out, so there is definitely gas at the rail.
After some testing, this is what I've come to...

Pin 21 on LH2.2 is the control signal to the fuel system relay. According to the document I've been using, it's supposed to show battery voltage in key position 2. With the key off, I have 12 volts, but in KP2, I only have about 1.72 volts. While cranking, it shows 1.6 volts. According to the document I am supposed to have 0-1 volt. Strange that goes over and the KP2 voltage is ridiculously low.
My question, though, is how accurate is this information? Am I supposed to have ~1.7V or 12V? That pin is connected to the fuel relay terminal 86/1. That pin shows the exact same voltage readings as the LH terminal.
Interestingly enough, this shows to be an ECU-switched ground, like pin 13 for the injectors... which doesn't work either.

I also noticed that there is a voltage drop between the fuel relay pin 85 and 86/2. 85 shows ~12.3V while both 86/2 and LH pin 17 show ~11.8V. The only way that could be a problem is the relay.

LH pin 9 (power to ECU) shows over 12 volts in KP2, and 10 while cranking. That should be sufficient, yes?

Did you bypass the boost pressure over-pressure switch?

I had done it before with no change, but I can try it again.
 
Wait, if you pulled the rail and injectors, did you make sure to connect the grounds on the mani? Won’t spray if not. A noid light is useful here.
 
Before I really knew what I was doing....or maybe if I'm severely undertooled, I have pulled the fuel rail, reconnected the grounds and fire the starter with the key to see if the injectors would spray. One time, I started a fire.

If you just pull a coil wire, secondary OR primary, you may still have spark jump a gap. You may want to pull both small wires off the coil and insulate them too. Or pull fuses, etc
 
After testing today and looking REALLY closely at the noid light, I can confirm that I have injector pulse. This was with the fuel system relay in place, not with the jumper, so the relay is not a problem. I think that problem is solved!
Maybe it's because of the resistor and low resistance injector setup that the noid light blinks so dim? Or is that normal?

Anyway, the car still won't start. I think the only plausible cause at this point is that all four injectors are cooked. The only way I think this could have happened is when the previous owner tried to fix the old ballast resistor, and managed to have all four injector wires make contact without first passing through the resistor. Probably cooked all four injectors and the old ECU.
Are we all in agreement here? Any other ideas before I buy a set of injectors? Any way to test them besides listening to them or pulling them and testing for spray again?
 
Back
Top