Need help S-heads. My fuel pump issue wasn't the issue. Here's the story>
10-27-2008, 04:18 PM
#1
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Need help S-heads. My fuel pump issue wasn't the issue. Here's the story>
Sat I just got into boost and the car died, CEL came on and the motor shut off. Car cranks but nuttin.
I'm trying to find similar experiences to sort this mess out.
Here's what I have so far:
I get a Cam and Crank position sensor codes
ECU fuse is fine
Fuel pump is fine
Charge hoses are all on
Swapped a cam sensor
It *seems* like there's no spark
Thoughts, similar experiences?
I'm trying to find similar experiences to sort this mess out.
Here's what I have so far:
I get a Cam and Crank position sensor codes
ECU fuse is fine
Fuel pump is fine
Charge hoses are all on
Swapped a cam sensor
It *seems* like there's no spark
Thoughts, similar experiences?
10-27-2008, 04:37 PM
#4
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^ Yep.Scott, you gotta very that Crank position signal is present.
IIRC., that crannk position signal initiates the start sequence.. gotta see that signal to be sure.
Wish I could swing buy, I have a scope ;-(
JP
Wish I could swing buy, I have a scope ;-(
JP
10-27-2008, 04:44 PM
#5
As the others have stated, you need a working cam position sensor to tell the ECU to fire the J17
fuel pump relay.
Here is some info in the FAQ:
<a href="https://forums.audiworld.com/s4s6/msgs/126842.phtml"> Cam Position Sensor info</a>
<a href="https://forums.audiworld.com/s4s6/msgs/149827.phtml">J17 FP relay info</a>
Here is some info in the FAQ:
<a href="https://forums.audiworld.com/s4s6/msgs/126842.phtml"> Cam Position Sensor info</a>
<a href="https://forums.audiworld.com/s4s6/msgs/149827.phtml">J17 FP relay info</a>
10-27-2008, 05:10 PM
#6
You need cam and both crank signals to start. Then just the two crank signals...
Cheat sheat:
Crank speed sensor: how fast is the engine turning?
Crank position sensor: where is the crank?
Cam position sensor: where is the cam?
The crank position sensor is somewhat redundant -- many cars get by with only a cam signal. But I suppose this compensates for belt slop by using the crank position for timing and the cam position just for phasing.
Crank speed sensor: how fast is the engine turning?
Crank position sensor: where is the crank?
Cam position sensor: where is the cam?
The crank position sensor is somewhat redundant -- many cars get by with only a cam signal. But I suppose this compensates for belt slop by using the crank position for timing and the cam position just for phasing.
