WONT START WHEN HOT! NEED HELP GUYS!

[RV302GT]

Yes, another hot start issue, but done a bunch of things and still no luck...any insight from you guys would be appreciated.

I have an 88GT and when i try to start it when hot, it is VERY laboured (like i have a dead batterie) and wont start. Needs 30-40 mins to cool down a bit and start again. I dont think its the batterie..yes, its 6yrs old but has no prob starting car after 2 weeks of sitting. I changed the starter and put a new 4 guage cable from the solenoid to the starter. Batterie cables are both new aswell. Tried jumper cables on the batt to the solenoid nut that the new cable goes to from the starter, while at the same time adding ground with the jumper cables, (used the power steering bracket). still no luck!!. Maybey i missed something or didnt do something right?....NEED help PLEASE!...thanx guys!

 

[04gtboy]

Sounds like your timing needs checked !

 

[RV302GT]

i thought about it but since it was set at 12 degrees last summer and havent put more than a couple thousand miles on it since..that it should be ok...but gonna check anyways...thanx for the tip!. if its still at 12...does that mean its not the prob?...or do i have to check something else timing related?...could it be the TFI?....i was also thinking about the solenoid and going to check the engine to firwall ground when i get a chance....running out of ideas though....thanx again!

 

[04gtboy]

Try settin it back to 10 degrees . Or maybe your starter is gettin hot or going bad.

 

[HISSIN50]

In a situation where you have a means of getting a jump, get the battery real hot where it won't start your car while you're in the parking lot of the parts store. Then pull it out, run in and have it tested (that sentence sounds dirty ).

Does this occur if you use a jumper battery? Doing that test helps rule out cables and cable connections vs the battery. If a jumper doesnt help, the battery itself might not be your issue.

 

[RV302GT]

Thanx for the tip. I didnt try jumping the car with another batterie because i was sure mine was in great shape, but i will do it asap! At this point i'll try anything,lol....As for 04Gtboys suggestion...thanx also but the starter in brand spanking new...i thought it was the cause but apperently not...as for the timing...well guess i can try that too. Thanx....anything else anyone can think of, please let me know. Does anyone think the module can be doing this?

 

[HISSIN50]

If the TFI module is bad, you lose spark. It's easy to check spark.

However, slow cranking has nothing to do with spark. Your engine should still turn over quite quickly. It's an issue with the starter, large cables or battery.

 

[rflow50]

Have you check the strarter.

 

[capri debris]

With a hot start problem, the FIRST thing to do is turn the timing back about 5 degrees no matter what it's currently set at. It's the easiest thing to do. If it makes things better... problem solved. If it doesn't, set the timing back where it was and start checking other things like the cables and starter.

 

[Mr. Rustypwnz]

ive done this lol

put a heat shield around the starter, or fabricate one, and run a beefy ground, you can run two if needbe, check the color on the stock ground strap, and look for discoloration, if there is, the thing has been getting really hot and needs a bigger wire, run a 4ga from the bellhousing to the stut tower, as your ground strap and it should clear this up, I had a car once(stang) do this to me everyday, finally took it to the mechanic and the starter was fine it was just getting heat soaked, the shield and the bigger strap made a world of difference!!!

 

[RV302GT]

Thanx guys, it seems the popular vote puts it with the timing or the a ground problem. First i'm gonna try the jump start test to rule out the battery and then i'm gonna retard my timing when its hot to see if that helps. While i'm at it i'll check the grounds i cant see now. I'll let you know how it turns out. One question though....if retarding my timing works....that means something isnt doing its job...no?. I've had my timing at 12 or 13 deg. for 12yrs now without any issues. What would be causing a no timing retard on hot start problem?....Thanx again!

 

[jrichker]

No Crank checklist for 5.0 Mustangs

Since some of the tests will bypass the safety interlocks, make sure that the car is in neutral and the parking brake is set. Becoming a pancake isn’t part of the repair process…

Check battery, terminal connections, ground, starter relay switch (also known as solenoid) and starter in that order. The clamp on with 2 bolts battery terminal ends are a know problem causer. Corrosion gets in the clamped joint and works its way up the wire under the insulation. Avoid them like the plague...

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection while trying to start the car: more than .5 volts across a connection indicates a problem.
See Automotive Test Tools for help for help troubleshooting voltage drops across grounds.

1.) Will the car start if it is jumped? Then clean battery terminals and check battery.

2.) Check the battery to engine block ground, and the ground behind the engine to the firewall.

3.) Jump the big terminals on the starter relay next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.

4.) Then pull the small push on connector (small red/blue wire) off the starter solenoid (Looks like it is stuck on a screw). Then jump between the screw and the terminal that is connected to the battery. If it starts, the relay is good and your problem is in the rest of the circuit.

5.) Remember to check the ignition switch, neutral safety switch on auto trans and the clutch safety switch on manual trans cars. If they are good, then you have wiring problems.

Typical start circuit...
Diagram courtesy of Tmoss &Stang&2birds

See http://www.autozone.com/images/cds/gif/large/0900823d80195963.gif for 88-90 year cars
See http://www.autozone.com/images/cds/gif/large/0900823d80195964.gif for 91-93 year cars.
See </title></head>"); newWindow.document.writeln("<body><div align='center'><img " + getWidth("yes") + "src='/images/cds/" + tpe + "/" + sze + "/" + pc + "." + tpe + "'></img></div>"); newWindow.document.writeln("<div align='center'><table><tr><td><FORM for 94-95 model cars.

6.) The starter may be hung, loosen up the bolts that hold it on, and give it a good whack with a big hammer. Tighten up the bolts and try again.

7.) Pull the starter and take it to Autozone or Pep Boys and have them test it. Starter fails test, then replace it. If you got this far, the starter is probably bad.

Starter solenoid wiring for 86-91 Mustang

Starter solenoid wiring 92-93 Mustang or upgraded high torque mini starter.

 

[RV302GT]

Well, it looks like the jury is in!!. I took Hissin50's advice (thanx Hissin!!!) and did the simple battery jump test, and needless to say, i was in total shock when it actually worked,lol. Now, i'm not an idiot,lol..although i do feel a little stupid now....but i really never considered the battery could be the problem since it didnt display any other normal symtoms. I have changed alot of batts over the last 15-20yrs but never for this reason. Usually they fail when its real cold outside, or the car has been sitting a long time or you've been running your lights etc for a while.....i've never seen one work great in all those conditions but fail when the car gets to operating temp. Well, i guess there is a first for everything,lol..Time to run out and get a new one. Just out of curiosity though..if anyone knows more about what may have caused this problem, i'd love to know. I just hope the new batt is not masking some other problem....i've wasted enough cash as it is. On that note....i want to say thank you to all who responded and tried to help me....YOU DID!!

p.s. how do i post pics?

 

[RV302GT]

pics of my White Steed

i hope this worked

 

[Tom Berkebile]

This is a very old thread but it came up first against my search for the subject matter.
I have found the solution!! My son's 2010 V6 had this issue. When the "motor" got hot it would not allow the starter to turn over the engine. It acted like a dead battery, but the battery was charged just fine. If you jumped the car, it would likely start but no guarantee.
I'll get right to the fix: It's the positive battery cable between the starter and battery.
There is material imcompatibility (galvanic action) between the steel of the goofy battery connector they used, and the copper wiring. Once the copper cable starts to age it becomes more and more resisitive. That makes it get hot during charging and keeps compounding the copper breaking down. Making is more incapable of transfering power to the starter for starting the motor. If you look at the 2 or 4ga wire going to the battery terminal connector it will be brittle and discolored. Brittle is the dead giveaway of this failure mode. I could not find a replacement cable last year when I finally came across this, so I bought about a foot of 2ga battery cable. I cut the old cable back the foot, soldered them together, heat shrunk the connection and put on a traditional lead battery connector.
My son's car was having the no start condition happen about once a month before this. I replaced two batteries, a starter, an alternator and was becoming very frustrated that I couldn't find the problem until this revelation. This wiring repair has completely removed the issue. For nearly a year now, my son's car has NEVER had a recurrence of this issue.

 

[General karthief]

This is a very old thread but it came up first against my search for the subject matter.
I have found the solution!! My son's 2010 V6 had this issue. When the "motor" got hot it would not allow the starter to turn over the engine. It acted like a dead battery, but the battery was charged just fine. If you jumped the car, it would likely start but no guarantee.
I'll get right to the fix: It's the positive battery cable between the starter and battery.
There is material imcompatibility (galvanic action) between the steel of the goofy battery connector they used, and the copper wiring. Once the copper cable starts to age it becomes more and more resisitive. That makes it get hot during charging and keeps compounding the copper breaking down. Making is more incapable of transfering power to the starter for starting the motor. If you look at the 2 or 4ga wire going to the battery terminal connector it will be brittle and discolored. Brittle is the dead giveaway of this failure mode. I could not find a replacement cable last year when I finally came across this, so I bought about a foot of 2ga battery cable. I cut the old cable back the foot, soldered them together, heat shrunk the connection and put on a traditional lead battery connector.
My son's car was having the no start condition happen about once a month before this. I replaced two batteries, a starter, an alternator and was becoming very frustrated that I couldn't find the problem until this revelation. This wiring repair has completely removed the issue. For nearly a year now, my son's car has NEVER had a recurrence of this issue.

There is an app........ ah, I mean a checklist for that: the 'no crank, no start checklist. I think it's in RESOURCE area. But in short, a voltage drop test would have revealed the crappy wires.
Glad you resolved the issue