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New cam/heads with no fire

Sean2857

New Member
Hey everyone. A couple months ago I purchased a 1990 lx convertible with no engine, trans, or ecm. It came from the factory with an automatic transmission but it was converted to a stick. The previous owners removed the engine, trans, and ecm to put in a different car. I'm in the process of putting it back together. I found a stock 5.0 out of a 92 foxbody, and a t5 to put back in the car. Before I put the engine and trans in, I installed a Ford racing e303 cam, New lifters, comp cams 1.7 rockers, GT40P heads off a mountaineer, GT40 intake, aeromotive adjustable fuel pressure regulator, BBK fuel rail, accel 19lb injectors, and trick flow valve springs. I also got an A9P computer (which is what was in the car before I bought it). I have the engine and transmission in the car along with the ECM. When I go to fire the car up, it'll start, then die a second or 2 later. I'm completely baffled why this thing won't stay running. I've checked to make sure the distributor is in correctly, I've tried another ECM, checked the rockers multiple times, fuel pressure is at 45 psi with no vacuum. When I installed the cam, I lined the crank and cam up dot to dot. Now just to give as much info as possible, the belt drive setup is not installed (alternator, ac compressor, water pump steering pump), i also do not have the exhaust hooked up. So no,, the 02 sensors are not connected. When the distributor it turned all the way to where the ignition module hits the waterneck, the car will fire right up and die within a second or 2. When it's turned the opposite way, it won't fire at all and sounds like the exhaust is under water. I'm completely lost as to why this thing won't stay running. If anyone has any ideas, please let me know. I'm beyond frustrated with this thing.
 

broncojunkie

Well-Known Member
Where did the distributor come from? Was it on the engine from the 92? You can take the ignition module off the distributor and most of the major parts stores can bench test it. They also sell a cheap tool to remove/install them, which is a good idea to keep around. If they test it, have them run the test a few times.

More importantly, have you checked your ignition switch? I replaced the switch in my 88 and had a weird problem. It would fire right up but immediately die. I finally realized that I could keep very slight pressure on the key as I released it, instead of just letting it spring back, and it would stay running. I never got around to replacing it and several years later, my buddy is still driving it that way. It just deters people from stealing the car lol!
 

Sean2857

New Member
Where did the distributor come from? Was it on the engine from the 92? You can take the ignition module off the distributor and most of the major parts stores can bench test it. They also sell a cheap tool to remove/install them, which is a good idea to keep around. If they test it, have them run the test a few times.

More importantly, have you checked your ignition switch? I replaced the switch in my 88 and had a weird problem. It would fire right up but immediately die. I finally realized that I could keep very slight pressure on the key as I released it, instead of just letting it spring back, and it would stay running. I never got around to replacing it and several years later, my buddy is still driving it that way. It just deters people from stealing the car lol!
The distributor is also brand new. Along with the module. I don't think it would be the ignition switch as the car ran before the engine was pulled.
 

broncojunkie

Well-Known Member
The distributor is also brand new. Along with the module. I don't think it would be the ignition switch as the car ran before the engine was pulled.
Did the distributor come with the module already on it? I would definitely get it checked, regardless. The last time I purchased one, the parts store had 3 in stock and all 3 were bad right out of the box. From what I understand, that's pretty normal...particularly with new ignition parts. Like I said, you can take it off in 5 minutes and the parts store folks can hook it up and test it for you. I've had the best luck with NAPA ignition parts. In fact, that's where I ended up getting my module when the other parts store couldn't produce a working one. That was several yrs ago and my buddy hasn't had to change it to this day. I've heard even the pricey Motorcraft modules are hit and miss, since production has now been outsourced to China.
 

Sean2857

New Member
Did the distributor come with the module already on it? I would definitely get it checked, regardless. The last time I purchased one, the parts store had 3 in stock and all 3 were bad right out of the box. From what I understand, that's pretty normal...particularly with new ignition parts. Like I said, you can take it off in 5 minutes and the parts store folks can hook it up and test it for you. I've had the best luck with NAPA ignition parts. In fact, that's where I ended up getting my module when the other parts store couldn't produce a working one. That was several yrs ago and my buddy hasn't had to change it to this day. I've heard even the pricey Motorcraft modules are hit and miss, since production has now been outsourced to China.
I'll definitely give that a shot. The car has spark, so I don't think that'd be the issue. But it's worth trying. I also got the accessory drive setup put back on today. Maybe it was a low voltage issue or ground causing the problem.
 

broncojunkie

Well-Known Member
If you have fuel pressure and you have spark, then your injectors may not be firing. There is a ground for the injector harness on the back on the engine. Iirc, it's a ring terminal that comes off the back of the harness and grounds to the firewall. An orange wire, maybe?
 

Sean2857

New Member
Finally figured it out. Turns out there's an ECM ground wire next to the battery that I missed. When I bought the car, I just tossed a battery cable on it and grounded it to the block. I didn't realize that there was another lead that came off the factory cable with a quick disconnect that went to the ecm ground. I hooked it up last night and it fired right up. Thanks for the help!!
 

broncojunkie

Well-Known Member
Good deal! Glad to hear it was a simple fix! Now that you mention that particular ground, I recall reading about how it's a commonly overlooked problem. I remember having to redo it on my 88 because it was in terrible shape, although, I think I addressed that before getting it running.
 
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