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Discussion Starter #1
Hey, i know there have been alot of threads about this, but i have read through them all but none of them have helped. So far i have replaced the cam sensor, tested it and replaced the pigtail. Replaced the ignition coils(all of them) replaced the ignition control module, spark plug wires and spark plugs, throttle body, and pcm. I checked through the whole wiring harness. I still have this code and it is the only code that comes up. If you can help that would be great.

Also if it helps the mods that i have done are obx headers, full 2.5 inch stainless steel exhaust, tuned pcm 90° header wires, and a 180° thermostat. Again thank you.
 

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Is it correct to assume you retested after replacing all of the parts you've changed?
Sadly, defective parts right out of the box are not uncommon.

If you retested and got the desired result of all those tests: 10v in, good ground, cam signal out, did you test to ensure that the signal is actually getting to the PCM?

If the connector for wire F is backed out or making poor contact or the wire has a break somewhere, then the Cam sensor signal is never reaching the PCM.
Same applies at the PCM end, of course.

If these are ok, then be sure the PCM ground is clean and tight.
Wouldn't hurt to ensure that the ICM ground is also clean and tight.
 

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Discussion Starter #5 (Edited)
The icm ground is good, i know because i pulled the bracket off soda ash blasted the plate and bracket then cleaned both with purple power, but i havent thought of the rest of that, and do you know where the ground to the pcm is?
 

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Discussion Starter #6
Also, yes i did reset the computer after replacement of the parts. And i have tested the parts hoping defective parts were the case
 

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Discussion Starter #7
Since it was a few month back when i did the tests, im going to go through with all of the tests again this evening when i get off work. If you could describe the process of checking the signal at the pcm then that would be great.
 

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The procedure is to disconnect the connectors at the pcm, turn the ign sw to ON and check for 5V at the PCM's Cam sensor connection.
If there is 5V present, then wiggle wires at various points to determine where the connection issue lies.
I don't have a FSM or an ALLDATA subscription to provide absolute info on PCM ground locations or the pinouts.
I have read that the connector is blue, is the radiator side connector, has a black wire and is #7 but you should verify this in a FSM or other wiring diagram source.

IIRC, Autozone has a number of electrical diagrams for when you sign up with them for free.

I sent you a PM with the url of the source page for the pinout info, as I don't know if posting the URL violates the forum TOS or not.
Looking on ebay, there's a FSM for 90 or best offer that you might consider.
An ALLDATA subscription also gives you access to that info for less money.
 

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Discussion Starter #9
Ok, this time the test came back with a good ground, no power and no signal from the cam sensor. The pcm was putting out the correct voltage, aswell as had a good ground. Where should i go from here
 

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The first link I gave you answers that on page 3

CASE 2: The multimeter DID NOT show 10 Volts when the ignition was turned on: This result indicates that the ignition module is not supplying power to the camshaft position sensor.

What this result means is that the camshaft position sensor itself is not at fault or BAD. Without these 10 Volts, the cam sensor will not work and produce a cam signal.


Now you need to determine why the ICM is not providing the necessary voltage to the cam sensor.
Could be as simple as a loose or corroded connector or a bad ICM, despite being new.
Part 1 -GM 3.8L Ignition Control Module and Crank (3X, 18X) Sensor Test

Check all the fuses in both fuse boxes to be sure one isn't blown, failing to supply voltage to the ICM.
I don't have a schematic to tell you which fuses might be the culprits.
 

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Discussion Starter #11
Unfortunately I found the problem. Unfortunate part is that last time i checked the interupter in the gear was there, this time its just a hole.
 

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Discussion Starter #12
Also, the tests were coming back wrong cause the multimeter didnt penetrate the 2 wires well, i checked again and all tests but the signal were good
 

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Discussion Starter #14
Yea, this weekend im going to do it the right way. I don't like doing things the shortcut way. And thanks for all of your help
 

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Discussion Starter #16
Mike K, you are a gentleman and a scholar. As soon as i finished and started it up the code went away. But with it being my luck, my whole way to work almost, it flashed check engine light at me. I don't have my code reader with me to see what they are. Love the car but it is the biggest pain ive ever owned.
 

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You'll really have to see what codes come up.
A flashing CEL is bad, since it indicates a catalyst damaging condition.

If the car was running fine when the CEL was flashing, perhaps. the PCM was "confused" by suddenly having a working cam sensor.

You're sure that the old magnet isn't stuck on one of the other teeth, so the PCM is now getting 2 cam sensor signals instead of 1?

A CASE relearn procedure shouldn't be needed, according to what I've read.
Here's the CASE relearn info, anyway
http://www.3800pro.com/forum/pcms-tuning/2-do-i-need-case-learn.html

It's a love/hate relationship with my cars for sure.
 

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Discussion Starter #18
No, i inspected the front of the block when i pulled the cover off and cleaned it, and the code was a p300, multiple random cylinder missfire. Was running perfect till yesterday morning, it stalled on the road and wouldn't start back. Still wont start, and haven't been able to check more than that i am no longer getting any spark from the coil packs. It's going to be difficult for me to find the problem as i cut off the tip of my thumb yesterday at work. So anything that you can think of to help would be great. When I get home I will check the icm, and if that isn't it i will start to check through the harness.
 

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Ouch--sorry to hear about your thumb.
Hope the injury was small enough to heal quickly.


Check all the fuses first.
There are fuses for the ICM, the PCM and other vital circuits--check them all.
A test light or DVOM works best and fastest.


Especially maddening to me is the fact that new parts nowadays seem just as likely to be defective out of the box as not--especially if you don't get OE replacement parts.
(Even ACDelco has an Advantage line that is far below OE quality.).
For reasons unknown--Bosch brand parts don't work well on the 3800 engines.
This includes Bosch spark plugs.

Assuming you had only changed the ICM in a vain attempt to diagnose the previous code, put the old ICM back in.
If the old ICM was bad, I would be inclined to try a known good junkyard OE ICM.
Buy one off a reliable Ebay seller if no local places have one.

Pull the new ICM and bring it to wherever you bought it and have them test it (not always conclusive as failures often don't occur until the part heats up.)

the other likely suspect is the crankshaft position sensor.
 

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Discussion Starter #20
Since the car will not start, or even spark the coils, I am planning to go home and start with checking the fuses as you suggested. If that doesn't work im going to pull the coils and test the icm working back from there, and hopefully allong the line before the pcm i find the problem. If it is as simple as the icm it is under lifetime warranty with autozone. To answer your question, yes I had changed it out due to frustration with the other code, but it had previously been changed out due to the oem part being bad last year. Hopefully it is as simple as a fuse.
 
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