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Topic: A CFI Conundrum (Read 4585 times) previous topic - next topic

A CFI Conundrum

Its a bit funny...but I wanted to drive the thunderchicken in the nice weather we had Fri. and Sat. since there was no salt on the road. So I go to start it and something has run the 9 month old battery down...AND the dang thing wont start.

The freaking injectors won't work.

So, I charge the battery and check the fuel pump for output...and yeah they're pressurizing the lines but the car wont fire. So, knowing that sometimes EEC IV provides a signal for the injectors based on a detection of spark discharge, I pull the No. 1 wire, stick a screw driver in it and try to ground it against the body. Needless to say the car is getting NO spark while the wife cranks. This goes on for a minute and just as I get ready to throw in the towel and swap the ignition module bolted to the distributor, suddenly I get spark and the injectors start working and the car starts up. I replace the wire and the car runs as happily as it ever has.

What the heck!

Anyone have any ideas as to what happened that would cause the car to not have spark?

I figure there was some corrosion under the cap where I haven't driven the car in a month or two to keep it out of the "brine"  VDOT throws on the roads. I looked and didn't see any corrosion, but I know grounding the wire to the body to check for spark is what got it to start.

A CFI Conundrum

Reply #1 –
What year is it?
CoogarXR : 1985 Cougar XR-7

A CFI Conundrum

Reply #2 –
You also didn't specify if it's a 3.8 or a 5.0.
Current: 1986 Thunderbird, 105k 3.8/C5, 2 tone  Midnight Wine/Medium Taupe, wing windows, wire wheel covers.


Former: 1985 Cougar GS 115k Oxford White/Regatta Blue, 5.0, full console, 14" 8 hole aluminum T-Bird rims, Edelbrock valve covers.

A CFI Conundrum

Reply #3 –
Check for ground to the ecm.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

A CFI Conundrum

Reply #4 –
1984, 302. Its making the carburetor and plug-and-play distributor option look more and more appealing.

A CFI Conundrum

Reply #5 –
Quote from: tbolt64;430643
1984, 302. Its making the carburetor and plug-and-play distributor option look more and more appealing.
All you need is a Holley 500CFM 2bbl, a Mallory 4309 FP regulator, and a Dura Spark dist/ign box.  Very simple.
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:

A CFI Conundrum

Reply #6 –
And a mechanical fuel pump
Current: 1986 Thunderbird, 105k 3.8/C5, 2 tone  Midnight Wine/Medium Taupe, wing windows, wire wheel covers.


Former: 1985 Cougar GS 115k Oxford White/Regatta Blue, 5.0, full console, 14" 8 hole aluminum T-Bird rims, Edelbrock valve covers.

A CFI Conundrum

Reply #7 –
Problem is likely in the dist(TFI or PIP), or could be coil or power to it, ign sw is famed for intermittent issues in these vehicles...

It's NOT going to be cap, rotor or plug wires...

A CFI Conundrum

Reply #8 –
Quote from: White85GS;430705
And a mechanical fuel pump
Nope. That's why you need the regulator. It drops the pressure in the existing return system so you can run your desired pressure at the carb.
84 COUGAR/90 HO, 1.7RRs, performer RPM,700DP, equal length shorties, stainless EXH ,T-5,Hurst pro-billet, KC clutch, 8.8/ 4.10s, line-lok, bla ,bla, bla.
71 COMET/289,351w heads, 12.5 TRWs, 750DP, Liberty TL, 9"/6.00s, 11.9x @112 , bla,bla,bla.

Never shoot your mouth off, unless your brain is loaded! ....I may get older, but I'll never grow up!....If you're not laughing, you're not living!  :laughing:

A CFI Conundrum

Reply #9 –
I know on my 83, I had a bad crank sensor that would intermittently make the car not start. But I think 84's got away from the EEC-III and crank sensors. It's something to consider if it's an early 84, maybe.
CoogarXR : 1985 Cougar XR-7
 

A CFI Conundrum

Reply #10 –
I was thinking the crank sensor thing also, not sure if your car has it though.
Mike

A CFI Conundrum

Reply #11 –
No, I have EEC IV... I am ready to drop in a points dizzy with petronix box and switch to the carb and  4 barrel intake with a Lokar TV cable and fuel pressure regulator.

The car has this awesome thing where it picks up a miss right after you first take off driving, I'd venture to guess when it switches from closed loop to open loop (or maybe from open to closed... cold operation to warm operation) and the miss gets worse and worse until the  thing chokes itself out and dies on the road and you have to sit there for a few minutes and then when it does start back up it runs just fine. When it dies it gets so lean the cats will smoke and stink!

The pain in the ass part is it only does this every now and then.

Maybe the EGR's vacuum is referenced by a ported vacuum switch thats screwing up occasionally.

Anyway, after its last round of shenanigans I bring the car home and check the sensors and wiring and pulled the codes (EGR fault and system rich)... so I replaced O2 sensor and repaired the coolant temp sensor pig tail where I found the two wires running to it got naked... and I found the plug for the TFI has been replaced, the plug to the coolant temp sensor has been previously spliced, and the PIP wires have been spliced and now if you wiggle the PIP while the car is running it will shut off. So that's freaking great! And just to make matters WORSE, the  thing does its little fake suicide routine on the side of the road AGAIN two days later.

So, it seems to me a mechanical means of fuel metering and simple ignition system is the way to go. Screw you CFI, which I have decided MUST mean "Cluster F$@# Injection"

A CFI Conundrum

Reply #12 –
How in the heck can you wiggle the PIP?

A CFI Conundrum

Reply #13 –
if you can I suppose you just found your problem.

A CFI Conundrum

Reply #14 –
The PIP is the in-line timing isolator...if you wiggle it while the car is running, the car dies because the splice on one side of it is right against the pig tail connector, That, I think, is the cause of the no-start issue. I just wonder about the other stupid-idity.  Are you conflating the PIP and the TFI module that is connected to the distributor?