OK, fourth time its done this. Hatch died on my way to work.

[LarsD]

It happened AGAIN. Only this time I couldn't get the car started immediately and I wreckered it home.

Same as before. Was rolling up to a light and it died. I tried to restart it and it cranked super slow like the batter was dead. I had to roll it off the road and call a wrecker to come pick it up. While I was waiting for the rollback I messed with it. It was cranking so slow the starter could barely turn the engine over. Five minutes pass and it tries to crank a little faster but no joy. Another five minutes pass, it cranks a little faster, and sputters for a split second. Five minutes after that, it starts to crank normally, but doesn't fire.

About this time I pulled the #5 plug wire and had my wife crank it. It threw spark, but still wouldn't fire. I checked the fuel rail, and it had fuel pressure. Few more minutes pass and I try again, cranks normally, sputters and tries to run but won't. Five minutes after that, I crank on it and it fires right up and idles.

At this point I wasn't going to risk it, so I waited for the wrecker to show. The guy got there, and I started the car up to move it is a better position for him. Got it home, rolled it off the truck, fired it up and parked it. It seems like it is running rougher then it was before, but I'm not 100% sure on that. I've been reading up on bad TFI modules, but the results seem to be all over the place as far as symptoms.

I'm about ready to take a saws-all to this thing and part it out.

 

[79'293stang]

TFI is never a bad idea. My car did similar things when the pickup was going out in the distributor, eventually it got to where it would not start any more after letting it cool off. The slow cranking did not occur. You may want to check out your grounds. I had a stalling in traffic issue and slow cranking in the past and ended up having a loose ground cable. Could be a combination of these or neither. Hard to tell.

 

[LarsD]

TFI is never a bad idea. My car did similar things when the pickup was going out in the distributor, eventually it got to where it would not start any more after letting it cool off. The slow cranking did not occur. You may want to check out your grounds. I had a stalling in traffic issue and slow cranking in the past and ended up having a loose ground cable. Could be a combination of these or neither. Hard to tell.

Since I've been through this several times before, I messed with the grounds. The ground cable is secure, plus I added two more grounding straps from the engine to the frame/body. I wiggled the cables while I was waiting on the truck and it made no difference.

 

[89stang1]

If its not a fuel problem i would change tfi first if thats not it i would change pip sensor...........ignition problems really suck!

 

[jrichker]

You have 2 separate problems.
Find and fix the slow crank first: it indicates a low votage or bad ground.
A voltmeter used to measure the voltage drop across connections while the starter is cranking the car will be required. Do the testing when the starter is having problems cranking the engine.

Voltage drop testing of connections and grounds.

Use a Digital Volt Meter (DVM) to measure the voltage drop across a connection or wire. Adding length to the test leads may be required, and does not affect the accuracy of the test. Use 18-20 gauge wire for the test leads if you have to lengthen them.

Voltage drop testing must be done while the usual load is on the circuit. If it is a starter, it has to be tested while cranking the starter. If it is lights, A/C or fan, they must be turned on high while testing. Fail to do this and you will not get accurate results

1.) Most grounds use the negative battery post as their starting point.
2.) The voltage will be small if the ground is good: less voltage drop = better connection.
3.) Be sure that the power to the circuit is on, and the circuit is being used in its normal manner. For instance, if it is a light circuit, the lights on that circuit should be powered on.
4.) To measure grounds, place one DVM lead on the battery negative post and the other on the wire or connector that goes to ground.
5.) Read the voltage drop: Light duty circuits (1-5 amps) should show .1-.25 volts. Medium duty circuits (6-25 amps) should show .25-.5 volts. Heavy duty circuits (26 amps up) should show .5-.75 volt drop. A voltage drop lower that spec is always acceptable.
6.)
See http://assets.fluke.com/appnotes/automotive/beatbook.pdf for help for help troubleshooting voltage drops across connections and components. .

 

[LarsD]

You have 2 separate problems.
Find and fix the slow crank first: it indicates a low votage or bad ground.
A voltmeter used to measure the voltage drop across connections while the starter is cranking the car will be required. Do the testing when the starter is having problems cranking the engine.

It only slow cranks when it dies, every other time I crank it the engine spins a half rotation, cracks right off and runs. I wish it did it all the time but it doesn't. When I was waiting on the wrecker yesterday I was wishing I had my fluke with me. If I can get it to die in my shop I will def measure the resistance of the cables though.

 

[89stang1]

yes i would fix slow cranking problem first

 

[LarsD]

yes i would fix slow cranking problem first

I can't fix it first. It only slow cranks when it randomly dies.

 

[91TwighlightGT]

Although your problem seems electrical, it may not hurt to reset the ignition timing. If it is too advanced it can cause a hard start, although it may not explain the dying problem. As you said, the TFI seems the most likely culprit.

I was thinking also maybe a bad distributor, although you said you were getting spark.

 

[LarsD]

Although your problem seems electrical, it may not hurt to reset the ignition timing. If it is too advanced it can cause a hard start, although it may not explain the dying problem. As you said, the TFI seems the most likely culprit.

I was thinking also maybe a bad distributor, although you said you were getting spark.

Yeah, enough spark to shock me when I was checking it on the side of the road. lol

It did this to me once before, but it was when I was trying to start the car and I had accidentally hooked up the plug wires starting with #5 as #1. I can't help but wonder if my Quarter Horse is messed up and it jumbling the firing order at random on me. I wish I had the presence of mind to detach the battery cable and clear the KAM to see if that fixed it.

 

[89stang1]

I can't fix it first. It only slow cranks when it randomly dies.

have a voltmeter with you when it dies then test....it does sound like possibly 2 problems, just saying get past slow cranking first a new pip or tfi wont help that. Even tho you did get spark it could still be a bad tfi or pip both can cause no spark when warm then spark returns as it cools try to check for spark right after it dies

 

[LarsD]

have a voltmeter with you when it dies then test....it does sound like possibly 2 problems, just saying get past slow cranking first a new pip or tfi wont help that. Even tho you did get spark it could still be a bad tfi or pip both can cause no spark when warm then spark returns as it cools try to check for spark right after it dies

Yeah I did that when I was waiting on the wrecker Tuesday. It was cranking slow, wouldn't fire, and shocked the hell out of me when I was checking for spark. So it had spark, but wouldn't start. The fact that it had spark, but it cranked slow and wouldn't fire makes me think the firing order is getting futz'd by the computer, Quarter Horse, or TFI/PIP.