cranks, no start, no spark....

[str8stang036]

I finally figured out why the starter wasn't getting power(a blown fuse). No it cranks, but doesn't start. I searched the forum for ways to check spark. I get no spark at all. I tried the screwdriver method and nothing, I tried spark plug ground on manifold and nothing, I tried a test light at the tfi coil connector and nothing.

I had the MSD 6btm hooked up and that wasn't functioning, No power at msd tfi coil(new). I also have a new 351w msd distributor.

I have a new tfi module, could that be bad? How do I check it?
Could the ecu be bad?

I got the motor fully built from the machine shop, with timing set. Could it be off so much as to not spark?

 

[HISSIN50]

The MSD box crapped itself too? It's now disconnected from the ignition system, right?

Put your test light across the two ignition coil terminals. Have someone crank the engine and look for the test light to flash really quickly (it will look like a pulsar star). If this happens but you dont have spark doing the tests from post 1, the coil is likely bad (or it could be a bad cap, rotor or coil wire).

Good luck.

 

[str8stang036]

I took off the msd box, it looked like it wasn't functioning. I went back to the stock setup without it. I didnt use a test like across the two terminals from the coil, but I used a digital meter to measure the current and I got nothing.

could the cap, rotor, wires, coil be bad even though they are new?
How can I test the tfi module?

 

[HISSIN50]

I took off the msd box, it looked like it wasn't functioning. I went back to the stock setup without it. I didnt use a test like across the two terminals from the coil, but I used a digital meter to measure the current and I got nothing.

could the cap, rotor, wires, coil be bad even though they are new?
How can I test the tfi module?

Your DMM probably will not work for this. Most DMM's have a dampening effect on rapidly fluctuating readings, so you tend to see some goofy average instead of the absolute amplitude (you see a level line averaged output instead of something that should look roughly like a square wave). If you have an LED test light or a noid light, they work well (they turn on and off really fast - you need something that goes on and off instantly, instead of glowing down like an incandescent bulb does).

The cap and rotor should not be bad, nor should wires.

If you can make the test-light test above work, but find you do NOT have a flashing test light, then the TFI is the next place to check. It's easiest to have a parts store test it for you.

Good luck.

 

[str8stang036]

thanks will try that tomorrow.

 

[str8stang036]

I tried the first recommended test, and got no light! If the tfi module is bad, will the injectors not pulse? Because I also tried that test and got nothing.

Let me make describe it to make sure I tested it right: I put the clamp of the test light to one end of the coil terminal and the sharp end to the other end of the coil terminal. Is that right?

Injector pulse test: clamp end to one injector terminal, and the sharp end to another injector terminal. Is that right?
Does the tfi module need to be grounded? I don't have a heat sink on it.

 

[HISSIN50]

A TFI can be bad and cause a no-injector pulse situation but it's very rare.

If you have lost both spark and injector pulsing, the PIP is more likely to have gone bad. If the TFI tests ok at the parts store, that even further suggests the PIP. With the key turned on and the fuel pump not priming, if you use a breaker to turn the engine over a little bit, you should hear the buzz of injectors firing and the FP coming on. If you don't, think PIP.

The TFI should not need to be grounded - it has a dedicated ground wire. Do ensure that any ground wires (with a loop terminal which go under the housing itself) are grounded. I thought I recalled one such ground wire but I might be thinkin of another application.

Good luck.

 

[str8stang036]

Isn't the PIP inside the distributor? I have a brand new 351w MSD distributor. It was in the box until I took it to the build shop. I am going to check the TFI tomorrow, possibly even get a new one.

How do I check the PIP? If it is bad, do you know if MSD sells that only?I can't believe I am so close, and I have all these problems!!

 

[HISSIN50]

Isn't the PIP inside the distributor? I have a brand new 351w MSD distributor. It was in the box until I took it to the build shop. I am going to check the TFI tomorrow, possibly even get a new one.

How do I check the PIP? If it is bad, do you know if MSD sells that only?I can't believe I am so close, and I have all these problems!!

Yep to the PIP/stator location (parts stores will call it a stator if you need the actual part).

To check a PIP with a meter, I'm thinking you could use an oscilloscope to measure the square wave output, or perhaps a DMM set to measure Alternator current. Our PIPs use an inverted signal.

If it's your PIP, there's no need for a performance unit - it's just a sensor (no more so than us using a performance IAC). I'd get a Motorcraft or Standard brand version and call it a day. Napa's PIP's are reportedly decent too.

Good luck.

 

[str8stang036]

i changed the tfi module for a new one, couldnt get it tested though. I did test the coil directly from the positive and negative coil and got no spark at all. I saw it has a crack at the top of the secondary. Funny b/c it has continuity, but secondary dont work.

 

[str8stang036]

I did all the test it says in the haynes manual. I now have power at the coil terminal connector, brand new coil. Tested the tfi for power and that checks ok. I check it for ground and I dont get any ground!

I check the PIP and the module like it says with the green wire using a light. When I crank it, its supposed to flash, it doesn't!! This must mean the PIP is definetly bad.

I looked under the cap, and found the tip of the rotor broken off. It wasnt touching the contacts on the cap. I got a new one, and still the damn thing wont fire up.Could this definetly mean PIP replacement?

 

[HISSIN50]

I did all the test it says in the haynes manual. I now have power at the coil terminal connector, brand new coil. Tested the tfi for power and that checks ok. I check it for ground and I dont get any ground!

Where do you not get any ground? There is a dedicated ground strap for the TFI as I recall. There's also a ground output.

I check the PIP and the module like it says with the green wire using a light. When I crank it, its supposed to flash, it doesn't!! This must mean the PIP is definetly bad.

This is the test we were trying to do above (the pulsing test light).

I looked under the cap, and found the tip of the rotor broken off. It wasnt touching the contacts on the cap. I got a new one, and still the damn thing wont fire up.Could this definetly mean PIP replacement?

It can also be a bad TFI or bad wiring.

 

[str8stang036]

Well I finally figured out what it was. First like the previous post said, the rotor inside the cap was broken. second the connector that I plugged in the distributor was the wrong one! Somehow I mixed up the connectors from backside of the motor to the distributor.

Now I have spark and it almost started. I am going to start playing with the distributor to see if its off.

Also, after I turn the ignition is the ccrm supposed to turn on with the fuel pump then shut off or stay on? I can get both combinations by removing a ground plug near the fuse box. Know anything about this?

 

[HISSIN50]

Glad to hear you got it fixed.

The FP should prime for 2-5 seconds upon turning the key to run. Then it shuts off until you crank the engine over.

Regarding the mystery plug: How many wires are on the plug, what color wires and which fusebox (underhood or interior)?