1996 4.0 ECM Problems

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SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #1

Pulled into the gas station last night to fill up and after pumping my gas the engine would crank but not start. From what I have found so far the fuel pump does run when the key is turned and there is fuel pressure on the rail but there is no power to the ignition coil.

Towed it over to the parts store on a dolly and had them put the computer on it this afternoon. The message on the computer was "Link Error". From this it sounds to me like it has gone brain dead on me but want some opinions before I jump into a new ECM.

Need to do it fairly quick as this is my only vehicle and my friend wants his truck back.

 

J

jneary

NAXJA Forum User

Location

springfield, virginia

• Jun 5, 2004

• #2

someti mes the crank sensors fail after a hot soak. thats my guess, especially if has never been replaced. i have seen bad aftermarket sensors so be careful.

 

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SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #3

If it was a crank sensor wouldn't I at least get a failure code out of the computer instead of getting the link error when trying to read it?

 

J

jneary

NAXJA Forum User

Location

springfield, virginia

• Jun 5, 2004

• #4

link error sounds like a problem with scan tool connection. i have never seen that with a chrysler scan tool

 

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SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #5

I was thinking about the crank sensor like you mentioned in your first reply, it is still the original at 155K miles. The ECM did die on me 2 years ago so that also came to mind when the scan tool wouldn't read anything.

I have a few other things I want to check in the morning, like whether the wiring is good between the test port and the ECM then I'll try to find a different scan tool to plug into it. Maybe then I'll come up with something.

Thanks for your help!

 

J

jneary

NAXJA Forum User

Location

springfield, virginia

• Jun 5, 2004

• #6

the coil can cause a hot restart problem but not as likely, especially if you said there is no power to the coil

 

S

SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #7

Guess I should have mentioned that I have a spare coil for this one. Hanging it in was one of the first things I did that didn't help me any.

 

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jneary

NAXJA Forum User

Location

springfield, virginia

• Jun 5, 2004

• #8

then i can almost guarantee its a bed crank sensor. if not it wouldnt hurt to replace it if you never have before, kind of for preventative measures

 

X

xjspyder

NAXJA Forum User

Location

562

• Jun 5, 2004

• #9

From working for DC for afew years,a shorted crank sensor can disrupt the 5 volt referance signal for the PCM.I reccomend disconnecting the CPS,then trying a "scan".If you get communication ,then you have a bad CPS

 

S

SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #10

Sounds like I have a couple of good ones to check on in the morning. I'm at home right now and my friend is holding the XJ captive until I finish using his truck. Gotta go to his house to do any work on it.

Thanks Again!

 

S

SparkChaser

NAXJA Forum User

Location

Martinsville, Indiana

• Jun 5, 2004

• #11

Experience strikes again, you guys nailed this one! Stopped at the dealership to pick up a sensor this morning, ended up finding it at the fourth one, $91 with Uncle Sam's cut. It started right up after replacing the sensor and is running as if nothing happened.

It seems that my '96 XJ is late enough in the model year that it got the newer OBD2 system, per the VIN number, so the sensor was a different part number. Just something for everybody to remember on this year, check the VIN to see which set of parts you need.