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Discussion Starter #1
Just replaced the 5.0 motor in my 93 SVT Cobra Mustang with a FRPP crate motor and have no spark. First thought was the coil since I replace the dist. with a new one including new TFI unit. Replaced the coil with no results. I next swapped out the dist. with the old unit, still no spark. Cranks like crazy and I seem to have fuel to the rail. What the heck? I've always had old school Hot Rods with no computors or EFI so this stuff is new to me. Am I missing something obvious?
 

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Like FE said, you need the connector hooked to the TFI module with power, ground and coil connections. That's all it needs to run, though the PIP and SPOUT wires for the computer to tell it what timing to use are necessary to drive it around normally. But it will run. So, verify you are getting power, ground, and connection to the coil, and that the 3 wires to the inside of the distributor are connected to the module. If you have that, you should have spark. Have you actually tested if you're getting spark to the plug wires and that they are going to the correct plugs?

David

Grab your volt/ohm meter. While there are many examples on the web, this is the distributor TFI module wiring by TMOSS:
 

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You are missing the Coil testing procedures that Kultulz likely has stuffed away in a folder somewhere.
I am not allowed to post TECH MATERIALS here as it is frowned upon.

Oh, the same material can be found in the appropriate year SHOP MANUAL (and I would be careful of powering circuits on an EEC application.
 

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Just replaced the 5.0 motor in my 93 SVT Cobra Mustang with a FRPP crate motor and have no spark.
Did the engine come with an instruction sheet as regards to retro-fits?

Do you have the FRP PN? I am curious.
 

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Discussion Starter #7
The FRP part number is M-6007-X302. I used this same motor in my Falcon hooked to a MSD 6AL and an MSD billet dist. with no problems. It's pretty much a direct replacement for the Mustang, nicer heads and a bit more cam but basically the same motor. I'm using stock ignition with a Summitt billet dist. that is for this vehicle and comes with the TFI module.

Here's what I have so far on Davids suggestions. On the TFI #1 pin 7.5 ohms, #2 pin 12.7 volts run position, #3 pin 12.7 volts run postion, #4 pin 12.7 volts start position. I have 12 volts going into and out of the coil that I believe supplies power to the #2 pin in the TFI. I've set the motor to TDC and installed the dist. with the rotor pointing towards the #1 on the cap. No spark. I've checked it with a timing light, an in line spark tester and pulling a plug and grounding it. I'm baffled.
 

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Altho I am by no means an expert on the late model crap, kind of baffles me as to why you have voltage at a supposedly "ignition ground".... I am sure someone will be along and give you some more insight...
 

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Altho I am by no means an expert on the late model crap, kind of baffles me as to why you have voltage at a supposedly "ignition ground".... I am sure someone will be along and give you some more insight...
He said 7.5 OHMS not volts :)

And Kultulz, this is EXACTLY where you need to place your TECH MATERIALS, as this is a purely non mechanical issue. One simply cannot look at the ign. module and tell if it's working...
 

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Discussion Starter #11
Yup, ohms not volts. I'm with you FE, don't know how to check the PIP signal. Sounds like it may not even be needed to start the car. It may not run well but I think it should run. If I'm understanding correctly the PIP signal changes the timing on the motor. Still baffled.
 

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On the TFI #1 pin 7.5 ohms, BAD - SHOULD BE NEARLY ZERO OHMS.
#2 pin 12.7 volts run position, GOOD. ALSO CHECK FOR ~ZERO OHMS PIN 2 TO COIL(-) KEY OFF.
#3 pin 12.7 volts run position, GOOD
#4 pin 12.7 volts start position. GOOD
I have 12 volts going into and out of the coil that I believe supplies power to the #2 pin in the TFI. CORRECT - KEY OFF SHOULD SHOW ~ZERO OHMS, AND CRANKING SHOULD SHOW ALTERNATING V/GND, WITH ~200-400V SPIKES IF COIL IS TRYING TO FIRE. CAREFUL WITH THE METER.

I've set the motor to TDC and installed the dist. with the rotor pointing towards the #1 on the cap. No spark. I've checked it with a timing light, an in line spark tester and pulling a plug and grounding it. I'm baffled.
^^^ READ NOTES IN QUOTE.

Ignore Pins 5 and 6 for now. I'd say you have a harness or connector issue with PIN 1 grounding the system. Find the resistance between pin 1 to ground or possibly to BAT(-) and repair.

Pull your coil HV wire from the dist cap and ground it, then clip your timing light or spark tester to that to test for spark as you go without having to re-install the rotor and cap each time. Before going too deep, you can test if Pin 1 ground is the issue by using a probe jumper from the connector Pin 1 to convenient tested ground (bypass ground jumper). Test Pin 1 and chassis ground to verify jumper for low ohms. Test for spark.

David
 

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I've seen 7ohms in cheap meter cables. Not saying in this case.
 

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Discussion Starter #16
In the wiring diagram I have, it shows the #1 pin wire comes from the PCM. I'm wondering if the PCM is shot. There is also the EEC-IV module that has something to do with sending a signal to the coil. I don't even know where these two units are located in the car. I have an idea I'm about to find out. Sure would like to hear that new motor run. Did I mention it has the original dealer installed Kenne Bell supercharger on it?
 

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Did I mention it has the original dealer installed Kenne Bell supercharger on it?
Damn to ad yer "old school" MSD stuff wont work .... dadnabbit....
 

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Discussion Starter #18
^^^ READ NOTES IN QUOTE.

Ignore Pins 5 and 6 for now. I'd say you have a harness or connector issue with PIN 1 grounding the system. Find the resistance between pin 1 to ground or possibly to BAT(-) and repair.

Pull your coil HV wire from the dist cap and ground it, then clip your timing light or spark tester to that to test for spark as you go without having to re-install the rotor and cap each time. Before going too deep, you can test if Pin 1 ground is the issue by using a probe jumper from the connector Pin 1 to convenient tested ground (bypass ground jumper). Test Pin 1 and chassis ground to verify jumper for low ohms. Test for spark.

David
David, I'm not sure I'm checking resistance on the #1 pin correctly. I just checked it by puttiing the meter (its a fairly decent Sperry meter) on the 200ohm (beeper) range, then put one probe in the pin and the other to ground and got zero ohms. Am I doing this correctly? I tried grounding the HV wire from the cap and testing it for spark. Nothing. Feels like I'm getting dumber as we go along. :confused: Electonics are not my strong suite.
 

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Sounds right, but how did you test to get 7.5 ohms on Pin 1 before?

Don't worry about the PCM/EEC just yet, as the engine will get fixed base (10° BTC) timing spark without any computer at all. Just the distributor and coil with wiring on pins 1 through 4 will give cranking spark. In a way, this is very similar to points ignition, where the trailing edge of one window crosses the center of the sensor, which triggers the TFI module to ground the coil (like points closing), and the leading edge of the next window passing the sensor triggers the module to fire the coil (points opening). Ignoring the electronic magic and focusing on the function simplifies it.

The timing advance during driving is on pins 5 and 6, sending a position signal (PIP) to the EEC and then receiving a SPark OUT reply telling the TFI to delay firing the coil until it's at the requested timing advance for the next cylinder. If the TFI does not hear a SPOUT reply (failed ECM or bad wiring), it defaults to base timing, and that's where we are at the previous paragraph. HTH

David

[EDIT] The point of the test on Pin 1 is to test the wiring from the TFI pin to chassis and battery ground. You are testing the wiring. Also, zero ohms means freely conducting though the wires - not infinite resistance (no meter reading). Verify that. It should read close to what you get just touching the probes together directly.
 

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Discussion Starter #20
David, first I want to thank you for taking the time to try and help me with this very frustrating problem.
I think I got the 7.5 reading off of the #2 pin by mistake. Testing #1 pin by putting one probe of the meter into the plug and the other to battery ground, I get nothing. I believe this is what you are calling infinite groud which I don't think is good. Although if this wire goes to the PCM couldn't that just be an open circuit?
 
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