ENGINE SHUTTING OFF AFTER GOING OVER SPEEDBUMP??

98stangv8

Active Member
Oct 3, 2003
1,036
0
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fayetteville, nc
About a month ago I went over a speedbump at like 3mph, and after getting over it, the engine shut off. I looked at everything, and it would not restart....turning over...but not starting. I unhooked the battery for a while...nothing. I played with the thing in the trunk, the intertia switch (it had not tripped or popped up)...and then it restarted....

I drove home, and it died 2 additional times...got out...played with the switch (never popped up)...and it would eventually restart

a couple days ago, it was sitting in my driveway idling...and it just died...I wasn't even in the car...I could not get it to restart at all.

I went to Ford, bought a new inertia switch..it was only 20 bucks. This didn't do anything.

ANY SUGGESTIONS ON WHAT TO CHECK?

Thank you!

Eric
 
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First thing I would do is put it on the scanner. You could have partially knocked loose a sensor like the CKP (crank position sensor), or a chassis harness connector or ground.

Have you tried to verify fuel pressure with a mechanical gauge right after it dies?
 
First thing I would do is put it on the scanner. You could have partially knocked loose a sensor like the CKP (crank position sensor), or a chassis harness connector or ground.

Have you tried to verify fuel pressure with a mechanical gauge right after it dies?


thank you for the reply! Can you put it on a scanner if it is not throwing a code? Is this something that has to be done at the dealership, as right now it won't start at all, and has to be towed there. Is there any way to check this stuff from the garage?

Thanks a ton!

Eric
 
I had that exact same problem with my old '94 Ford Ranger. It would run great for an hour or so and them all the sudden, unexplained it would die. It would turn over, get plenty of spark and fuel, but it would just not start. I'd screw around with it for half an hour and then out of the blue it would start up and run fine again.

....turned out to be loose pin connectors where the wiring harness attaches to the EEC. Might be something you'll want to check out. :)

Try wiggling the connection around a little, then attempt to start it again.
 
thank you for the reply! Can you put it on a scanner if it is not throwing a code? Is this something that has to be done at the dealership, as right now it won't start at all, and has to be towed there. Is there any way to check this stuff from the garage?

Thanks a ton!

Eric

The car can be scanned at any time regardless if any codes are present or not. If you don't have a way of scanning it yourself, you can go to Autozone or somewhere else and they will scan it for free. There is a code for just about every single electrical circuit on the powertrain harness. If it is electrically related, there is a decent chance you will have a code.
 
First thing I would do is put it on the scanner. You could have partially knocked loose a sensor like the CKP (crank position sensor), or a chassis harness connector or ground.

Have you tried to verify fuel pressure with a mechanical gauge right after it dies?


I have a little OBDII scanner and it didn't show any codes...if I get it to Ford, I will have to tow it since it won't start at all now...I checked the ground by the main fuse box from the battery...

Where are the chassis grounds located?


Eric
 
I had a similar problem..........check the pin connections for your cam positioning sensor........your car will turn over but not start........also check your fuel rail pressure.........fuel pump could be going out!

"ED"


where are the pin connections for the cam positioning sensor?

I am getting good fuel...I can smell it coming out the exhaust when I try to start it..


Thanks!
 
Did you check the connection at the computer harness under the passenger side kick panel like I mentioned?

I just went out and tried it now...wow, what a tight squeeze down there...nothing changed.

I am stuck now...do I get it towed to Ford, and make sure they will work on my car after being modified...do I get it towed to a "mustang place?"

Any other thoughts?

Where would loose grounds be located?
 
Here is a possibility. Pull the chip and see if it starts. My guess is the chip/J3 port connection wasn't so good and going over a speed bump it came disconnected completely, much like pulling a chip with the key on. It will fry the chip and/or the computer. If you are lucky and it starts without the chip, then just the chip is bad. If you are not lucky, maybe the processor is bad too. This is one reason people go with an Xcal - but it is a rare occurance.
 
There are quite a few chassis grounds, one for the block, one on the bell housing, one under the driver's side middle of the car, one back by the fuel tank, etc.

I would also check to see if your chip popped loose. Just start looking under the car and wiggling and making sure all your electrical connectors that you can reach are fully seated.

Youn said you only went over the speed bump at 3 MPH....are you sure you weren't going just a "little" faster?:D
 
There are quite a few chassis grounds, one for the block, one on the bell housing, one under the driver's side middle of the car, one back by the fuel tank, etc.

I would also check to see if your chip popped loose. Just start looking under the car and wiggling and making sure all your electrical connectors that you can reach are fully seated.

Youn said you only went over the speed bump at 3 MPH....are you sure you weren't going just a "little" faster?:D


3mph may even be on the fast end...because of my side exhaust, I drag over them...so I literally almost come to a complete stop going over it..

I will check the grounds and see what I can find..

Thanks for your thoughts!
 
Here is a possibility. Pull the chip and see if it starts. My guess is the chip/J3 port connection wasn't so good and going over a speed bump it came disconnected completely, much like pulling a chip with the key on. It will fry the chip and/or the computer. If you are lucky and it starts without the chip, then just the chip is bad. If you are not lucky, maybe the processor is bad too. This is one reason people go with an Xcal - but it is a rare occurance.

I agree. Pull the chip and check the connection. A lot of people have had problems with chip losing contact with ecu. Pearl.