Tach not working/check engine light

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Dec 15, 2008 | 03:03 PM

Bad Chad

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From: Huffman, Texas

Tach not working/check engine light

A few months back I had a 6.0 installed in my car and the tach worked fine and the check engine light was not on.

After the motor was installed the tach quit working and the check engine light is on. When I put a scanner on the car is says the signal for cam sensor is low. I put in a new cam sensor and still the same code comes up. I was told to check the wires that run along the passenger headers to make sure they are not touching. Well they were so I fixed them and still nothing... When I replaced the transmission this weekend I found the plug for the knock sensors was not plugged in so I plugged it in and checked the connection on the cam sensor and everything seemed fine.

Does anyone know what it could be? I have to get the car inspected this month so I need to get the check engine light off and it would be nice to get the tack working. I checked the fuses by the door panel, is there another place that has fuses?

Dec 15, 2008 | 03:08 PM

Dirty 30

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From: Dallas, Tejas

crank sensor?

Dec 15, 2008 | 03:17 PM

kornfreak_401

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From: BCS/DFW TX

crank position sensor on the right side of the block/oil pan??

Dec 15, 2008 | 04:24 PM

Sales2@Texas-speed

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From: Texas!

Swap the outer two wires on the can sensor harness. This is very common, especially with GEN4 engine swaps into Gen3 cars. The symptoms are hard starting, no/sparatic tach signal, DTC code thrown.

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Dec 15, 2008 | 04:31 PM

01Z0H6

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From: Hideaway Tx

Guarnteed that is what it is... Had it happen to me once aftera motor install.. The plug is not snapped in to the sensor..

Quote:

Originally Posted by Dirty 30

crank sensor?

Dec 15, 2008 | 04:44 PM

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

Swap the outer two wires on the can sensor harness. This is very common, especially with GEN4 engine swaps into Gen3 cars. The symptoms are hard starting, no/sparatic tach signal, DTC code thrown.

This sounds eactly what is going on.... Sometimes it will not crank and just backfire a little through the exhaust. I hope this is not it, I really don't feel like pulling the intake again. LOL

Quote:

Originally Posted by PewterY2KZ28

Guarnteed that is what it is... Had it happen to me once aftera motor install.. The plug is not snapped in to the sensor..

I will try the cam sencor, but from what what Matt is saying it exactly what the car is doing.

Dec 15, 2008 | 05:13 PM

Sales2@Texas-speed

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From: Texas!

I'd bet lunch on the cam sensor

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Dec 16, 2008 | 10:10 AM

Sales2@Texas-speed

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From: Texas!

Did you get a chance to check this last night?

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Dec 16, 2008 | 10:33 AM

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From: Tomball, Tx

You must be hungry Matt haha

Dec 16, 2008 | 11:03 AM

#11

Sales2@Texas-speed

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From: Texas!

HAHA! Neh. Just curious

No lunch required!

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Dec 16, 2008 | 12:56 PM

#12

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

Did you get a chance to check this last night?

is there a way to check it with out pulling the intake? If I have to pull the intake I may do it tonight.

Dec 16, 2008 | 01:16 PM

#13

Sales2@Texas-speed

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From: Texas!

Is this an Gen4 swap that has the cam sensor in the front cover? If so, you can swap the outer two wires up there at the front cover as well!

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Dec 16, 2008 | 02:34 PM

#14

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

Is this an Gen4 swap that has the cam sensor in the front cover? If so, you can swap the outer two wires up there at the front cover as well!

No, this has the sencor in the back of the intake like the LS1...

Is there a sencor in the front? I was only aware of the one in the rear of the block.

Dec 16, 2008 | 03:09 PM

#15

Sales2@Texas-speed

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From: Texas!

No, it'd just be in the rear. It will not be an issue where you need to swap those wires if it's still in the rear. More likely, the sensor is bad, or the wiring to and from the sensor to the PCM is cut/frayed/etc.

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Dec 16, 2008 | 03:32 PM

#16

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

The cam sencor is new, and all the wiring looks good...

Dec 16, 2008 | 03:55 PM

#17

Sales2@Texas-speed

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From: Texas!

What is the code number?

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Dec 16, 2008 | 05:41 PM

#18

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

What is the code number?

I can't remember, I will have to get the scaner from my brother tomorrow...

Tonight I'm going to check some wiring and the connections to the computer, maybe something is loose.

Dec 16, 2008 | 05:48 PM

#19

Sales2@Texas-speed

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From: Texas!

Yea, check to make sure the pins coming out of the PCM are straight, not pushed in farther than others, etc...even a little bend can wreak havoc on the rest of the systems!

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Dec 16, 2008 | 08:03 PM

#20

Bad Chad

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From: Huffman, Texas

Quote:

Originally Posted by Matt@Texas-Speed

Yea, check to make sure the pins coming out of the PCM are straight, not pushed in farther than others, etc...even a little bend can wreak havoc on the rest of the systems!

Does an unplugged connector justify hanging the motor installer????

I know it was an Honest Mistake so I'm not going to choke him too bad the next time he works on the car.

After checking the connectors for the computer and other various connectors I found this: