93 3.0l OHV no spark but cranks fine

Rybins · 03-12-2007, 07:08 PM

My car died last Tuesday (really cold) right after I started it. Since then, have replaced coil and coil wire and had the ignition module checked out of the car. All fine and still no spark. I have 2 questions. What is the pinout for the ignition module and how can I check to see if the PIP (Profile Ignition Pickup) is working? OK, 3 questions, how can I bypass the ignition switch? Any other thoughts are totally welcome!
Thanks!

ABE · 03-13-2007, 02:05 PM

I do not have an answer to your 3 questions.

Presumeably you have checked the ignition at the spark plugs with a known good plug connected to several of the plug wires? If you have no spark, have you tried the primary circuit at the coil to determine if there is voltage from the ignition module?

I am not sure about the 3 liter but I think there are 6 openings in the female connector at the coil of which 3 are used. #1 is missing a lead, #2 is neg (ground) for coil when ignition switch is in run, #3 is pos (live) when ign switch is in run and start, #4 is pos (live) when ign switch is in start, #5 and #6 are not used. If there is current as noted and the coil is new check the distributor. You did check the coil mounting had a good ground and not corroded?

The cap can be cracked so look carefully on the outside, remove cap and check the inside for evidence of arcing or tracking. Check the rotor and the pickup points around the cap for wear/damage. Check the center coil connection on inside of cap and the top of the rotor, usually a carbon brush that is spring loaded to contact rotor.

If there is no voltage to the coil then the wiring back to the ignition module needs to be checked and/or the wiring to the switch.

Hope this helps.

Rybins · 03-13-2007, 06:10 PM

Thanks Abe! One spark straight from coil, then nothing and I get a single spark each time I turn it off and start again. There is power at the coil. #4 on the ignition module harness is supposed to be 12V when in start according to my manual, too. I'm getting only 2V steady at run and start. #2 and #3 are 12V at run. Having a hard time tracing that #4 wire. Have it back to the main harness at the firewall then I'm lost. I took the ignition switch out and it checked out fine which makes sense since it will crank no problem. Where do you think that #4 wire gets its juice from??

ABE · 03-14-2007, 05:52 AM

Both # 3 and #4 need to be live in start. The EEC computer is located in passenger compartment on passenger side behind the glove box (I think). Check the colour of the wire at the firewall and the connections at the EEC computer. The ign switch start position should be providing the power and my manual shows it going to the EEC computer. So there must be a connection to allow seperate paths for ign and starter relay. Have you checked the switch for both these circuits (starter relay is known to work)?

Rybins · 03-14-2007, 07:44 AM

Thanks again ABE!! Is the starter relay the same as the starter solenoid? Older Tauri had a relay on the left fender by the battery but mine doesn't. A big fat bundle of wires comes from the firewall behind the computer but doesn't seem to go directly to it the EEC. I'll look more closely. The ignition switch harness has only one wire wire that's hot in START. Now I've been trying to trace that wire the other way toward the computer. Could a bad pickup in the distributor affect the ignition power at the icm harness??

ABE · 03-14-2007, 10:12 AM

Yes, the '93 has the relay (solenoid) built into the starter. There must be a connection somewhere for the EEC ignition circuit (in start) because of the neutral start switch being in the engine compartment. The neutral start switch is on the transmission where the shift lever rod connects. Since your engine turns the switch is probably good, but the wire (colour R/LB) to the ignition module comes from it. The other wire for the EEC (colour LB/Y) may be connected at the switch too, but I don't know.

Rybins · 03-15-2007, 11:40 AM

Thanks ABE. Look at this post I found on a Google group. No answer though!

"Engine shut off instantly like a switch was flipped as I was driving
down the street. Towed the car home. Starter turns engine over but
won't start. There is no spark from the coil. Coil primary and
secondary tested good. Ignition module connector primary voltage
tested good. Wiring harness connector #2 tested good, connector #3
tested good, connector #4 had no voltage. I don't know what the
white-pink wire on #4 does or goes to. The coil wire tested good. The
ignition module tested good at the AutoZone. Replaced the distributor
in order to test the stator assembly but the engine still will not
start."
Exact same problem I'm having. Wires on my ign module harness are from top to bottom, grey/orange, yellow/green, white/pink, red/green, tan/yellow, orange/red. According to my info, the white/pink is "Ignition Diagnostic Monitor" to the computer. Wow, I am confused!!!

Rybins · 03-15-2007, 06:43 PM

UPDATE: CCD TFI module looks the same as the one with "start" at the #4 wire on the harness but instead has a very different pinout. Therefore, all my wire tracing and switch checking was for naught! CCD can be identified by #4 wire going directly to the computer and is black as opposed to the "push start" module which is usually grey. Here's the URL to the article http://capitolautomotive.com/pdf/cccnewsletter.pdf

ABE · 03-16-2007, 07:11 PM

I can see why you would be confused. The article is not that helpfull to solving your problem. I think you have the push start system rather than the CCD system because the Haynes manual refers pin #4 on the module input to the start switch in start mode. The push start is grey and the CCD is black so what colour is your ignition module?

I will try to match your wire colour to my wiring diagram, and advise what I find.

ABE · 03-16-2007, 08:10 PM

The colours do not match my wiring diagram at all. So lets look at the colours for the components in the sequence we need:

Ignition coil: 3 connections; black ground back to ign module; red/light green for positive battery connection; dark green/yellow switched circuit from ignition module (etc). Confirm black wire ground, and red/light green has power with ignition on. Confirm dark green/yellow wire flashes in start mode or stays on. If all tests out as noted then problem is with secondary circuits such as coil, distributor, etc. But from previous posts ground is ok, ign switch battery power is ok, but switched circuit is dead in start and run.

Ignition module: 2 output connections; black ground to coil; dark green/yellow to coil tach (switched) terminal and tachometer in dash and ignition suppression resistor and electronic control assembly. We covered the testing of these circuits under ignition coil.

Ignition module: 5 inputs; red/light green from ign circuit (same as coil pos battery connection); red/light blue from ign switch start position after neutral safety switch; dark blue (DB is colour) from electronic control assembly to ignition module; yellow/light green from electronic control assembly through shorting plug to ignition module. Your pin #3 (red/green) appears to match the first wire above and should be 12v with ign on and start; your white/pink pin #4 should match with the above red/light blue however my diagrams say white/pink is the start position wire at the ign switch rather than the neutral safety switch. If pin #3 at ignition module is 12v and pin #4 is dead then the problem should be in the connection to the neutral safety switch.

Hope this helps.