sc hard starting probs

joker77_2005

Registered User
when my 92 sc is warm it wont spin over right when i try to start it,it all but spins over like it is hydro locking from coolant or fuel.i did the 3 layer head gaskets and cheked the coolant system and found that was not the cause,i did a fuel pressure leak down test for a bad injector and still no problems found,i am on my 3rd new ford starter ,plus a new firewall selonoid and new power and ground wires,plus a new optima battery
any ideas on a solution?
thanks
mike
 
Did you use new head bolts or have your block machined and checked before you did the three layer head gaskets? Check your plugs yo'.

Peeked at your clutch lately? is it still in one round peice?


Your going to have to be more descriptive if you want good answers.
 
joker77_2005 said:
when my 92 sc is warm it wont spin over right when i try to start it,it all but spins over like it is hydro locking from coolant or fuel.

Try to be a tad more descriptive.
When you turn the key what happens? If you jumper the fender mounted relay what happens?

You should test the current draw if you think it's the engine making it hard to turn. You may have a bad ground, or a bad power cable going to the starter.
 
when i aquired the car it was doing this,hard starting when warm,i thought a head gasket was leaking and filling the cylinder up with coolant and causing it to crank over slow and hydrolock,it almost as if one cylinder is getting to advanced of a spark timing .
im use to running a old carb v-8 and if i had this problem on one of those i would retard the timing some.
i did a timing checkon the sc and found that i am at 20 degrees btdc which was correct.
i have all new ground and power wires,starter and selonoid on the firewall,all new from ford (not some cheap advance auto parts stuff)
i have burnt up at least 3 new starters from ford so i dont think that the battery cables are the culprit.
i run 93 octane in it all the time and rarely ever drive it with more than 3/4 gas pedal to the floor. once i get it to start it runs great no problems,no vacum leaks
i know that my pistons are not smacking valves or spark plugs.
if i jump the relay on the fenderwell or on the starter it self i still have the problem.
also it is an automatic transmission
any other description yall mite need to help me
this sc is starting to be a pain in my butt,i have put more money in to the sc than i have my 13 second v8 tbird
 
What happens if you start the car in neutral rather than in park? Does the cranking behavior change?

It sounds like you're throwing money at it, gotta do basic trouble shooting, not part swapping.

Try using a breaker bar on the crank bolt to test effort to turn the engine.

How is your fuel usage? Are you fairly certain the fuel pressure regualtor is o.k.?

How does it sound when it's cranking slow and finally starts? Any signs of a misfire or ignition timing issue, backfire?
 
well it starts the same way in nuetral or park
fuel useage...well i get about 350 miles to a tank,fuel preesure regulator is workin
im a maryland state inspector so if i think it is questionable i replace it.
when the problem occurs the engine cranks over at the spped it should butt it acts as if one random cylinder is kicking back and causeing the engine to stop spinning for a second,while this is happening i am getting raw few vapor out of the tail pipes
if i crank the motor over with a wrench it takes the same effort as another sc that i have sitting here
i am not getting a backfire or missfire,it is almost as if the timing is too far advanced
 
If you search the boards, there are several people that have this issue at random. I cant find any of them with a real fix. I have the exact same problem as you, but mine is every 10th time or so and only when hot. It hasnt burned up a starter yet, as mine is the original piece! Just like you said, cranks at full speed until it feels like it hits a cylinder full of something and slows down, runs great once started, and never does it cold. Mine puffs out black smoke after one of these starts, so I assume I have an injector thats leaking down. Let us all know if you find the cause.
 
Has the cam sensor or the cam sensor drive been removed? That would mess with timing a tad. Try disconnecting the cam sensor for a few days and while it'll be hard to start as the computer guesses what to do, if the cam sensor was causing your hard cranking, it would go away.

Are you sure the crank pulley and harmonic balancer are not moving on the crank snout? if the balancer has failed, it may allow the center section to stay in place on the crank as the outer section flops around. That'll mess with the CID signal and could cause a misfire.

Otherwise I'd recommend using a breaker bar on the crank bolt to get a feel for how hard it's turning over to see if it seems wrong. I guess you could have lost a lifter, push rod, or dropped a valve.
 
I agree with Mike

When the cam sensor starts to go out or there is a problem with the DIM the computer enters a get home stage. You run but the timing won't always been on so you have to turn the key on and off to reset the computer till it finds the right cylinder to fire on. If you just keep trying to start without reseting you'll burn the starter.
 
good news ...i found the problem.it was the ignition module,no more hard starting problems....now the bad news the dam pressure switch for the teves brake system went out....oh well you win some you lose some
 
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