Well, I changed the 7x with a AC delco or a Borg Warner (OEM equivalent), not sure, but it didn't change the 5/2 fire problem.

And I realized later that the coils probably aren't the problem as it was not sparking the 5/2 on the old ICM and it didn't have any coils on it at the time. I just swapped the harnesses. Also, tried jiggling those wires to try to find an open, but never got any results.

I'm gonna have to see the wave pulses to see whats going on I bet.

 

http://www.google.fr/url?sa=t&rct=j&...,d.d2s&cad=rja



https://books.google.fr/books?id=-Yq...ed=0CEUQ6AEwBA

a beginning to learn.

PCM order ICM from 400 RPM.

on the first link , near the end tree pulses with différent values ??

 

Partie 2 -Comment Testez la manivelle capteur 24X (GM 3.1L, 3.4L)

The signal that the 24X crank sensor produces goes directly to the Powertrain Control Module (PCM = Fuel Injection Computer) and is NOT critical for the activation of spark and fuel injection.

 

Sorry is better with this link :

http://www.google.fr/url?sa=t&rct=j&...85970519,d.d24

 

Thanks for links, but I haven't been able to check that yet.

I DO HAVE A MAJOR UPDATE!!!

I took the ECUs to the parts store and they checked them and BOTH PASSED!!

So I started to look at the wiring harnesses where it meets clips and hold-downs etc and I found one broken at the clamp on the ECU bracket! It went to the ECU on the driver side plug, front wire, so whatever one that is, it will mess up your 5/2 coil!! I soldered it back and used shrink wrap to secure it, and it fired right up!

PHEW PROBLEM... ALMOST... SOLVED!!!

BUT A NEW ONE!!

I couldn't get it to RE-start the next day, because the injectors weren't firing! I checked the CAM sensor for signal, and it was working, so I don't know why that was going on.. I used some starter fluid and it started. Then, killed it and it restarted.

I let it run long enough to start putting the coolant back and it was smoking some, not like bad rings, but white smoke still.. It also gave a P0335 code, CKP out of line, but I figured that would happen..

Will this go away on its own, or do you really need a TECH-II to reset that code?

I just turned it off, and will get back to it on Wends, as its going to be freezing the next few days.

THANKS ALL For sticking thru this with me, even if you didn't post, just following along is helping inspire me to get this van working right!

 

HI,*
to erase the DTC, it is possible to disconnect the battery several minutes. shunt the cables more and less when one is disconnected if it does not work.
But the best with this type of vehicle is to have a MiniScan to read the data stream, read Freeze data, read DTC and clear.
I have one and it is essential ($ 100 on ebay).

I am delighted that you have advanced.

I do not understand how a damaged wire ( what?) on the PCM can disrupt an ignition coil.

at last,
after having searched and read everything on scannerdanner , I retain this:
On our ventures, the 7x CKP is of the magnetic type with a two wires connector. It is connected to the ICM.
The signal is AC type, measure with a voltmeter or oscilloscope and we have 300mV (RMS ?). this will be validated by readers, I can do it for a month, but with a scope.
I do not see at all, how, from a wave of this form, the ICM can know the good coil to be exploited at the right time.
again according scannerdanner, CKP 24x only serve from 400 rpm,
and this I checked.

We advance slowly but we advance! and w'll unterstand.

 

ELECTRONIC IGNITION (EI) SYSTEM DESCRIPTION

The electronic ignition (EI) system is responsible for producing and controlling a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy, and control of exhaust emissions. This ignition system uses one coil for each pair of cylinders. Each pair of cylinders that are at top dead center (TDC) at the same time are known as companion cylinders. The cylinder that is at TDC of the compression stroke is called the event cylinder. The cylinder that is at TDC of the exhaust stroke is called the waste cylinder. When the coil is triggered both companion cylinder spark plugs fire at the same time, completing a series circuit. Because the lower pressure inside the waste cylinder offers very little resistance, the event cylinder uses most of the available voltage to produce a very high energy spark. This is known as waste spark ignition.

The EI system consists of the following components:

• Crankshaft Position (CKP) Sensors The CKP sensor B is a variable reluctance sensor. The magnetic field of the sensor is altered by a crankshaft mounted reluctor wheel that has seven machined slots, six of which are equally spaced 60 degrees apart. The seventh slot is spaced 10 degrees after one of the 60 degree slots. This sensor provides the ignition control module (ICM) with 7X signals, or seven pulses for each revolution of the crankshaft. The pulse from the 10 degree slot is known as the sync pulse. Both of the sensor circuits are connected to the ignition control module (ICM). A signal converter within the ICM produces digital 3X output pulse to the powertrain control module (PCM), the 3X reference is known as the low resolution engine speed signal.

The CKP sensor A contains a hall-effect switch. A hall-effect switch is a solid state switching device that produces a digital ON/OFF pulse when a rotating element passes between the sensor tip and a magnet. This rotating element is called an interrupter ring or blade. In this case the interrupter ring has 24 evenly spaced blades and windows and is part of the crankshaft damper assembly. This sensor provides the PCM with 24X signals, or 24 identical pulses per crankshaft revolution. The 24X signal is used for enhanced smoothness and idle stability at a lower calibrated RPM. The PCM supplies the sensor with a 12-volt reference, low reference, and signal circuit.

• Camshaft Position (CMP) Sensor The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the camshaft. The CMP sensor does not directly affect the operation of the ignition system. The CMP sensor information is used by the PCM to determine the position of the valve train relative to the crankshaft position. By monitoring the CMP and CKP signals the PCM can accurately time the operation of the fuel injectors. The PCM supplies the sensor with a 12-volt reference, low reference, and signal circuit.
• Ignition Control Module (ICM) And Ignition Coils Three dual tower ignition coils are mounted to the ICM, and are serviced individually. The ICM performs the following functions:
• The ICM receives and processes the signals from the CKP sensor B.
• The ICM determines the correct direction of the crankshaft rotation, and cuts spark and fuel delivery to prevent damage from backfiring if reverse rotation is detected.
• The ICM determines the correct coil triggering sequence, based on the 7X CKP signal. This coil sequencing occurs at start-up, and is remembered by the ICM. After the engine is running, the ICM will continue to trigger the coils in the correct sequence.
• The ICM produces and inputs 3X reference signals to the PCM.
• The ICM contains the coil driver circuits that command the coils to operate.
• The Powertrain Control Module (PCM) The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. Ignition control (IC) spark timing is the method the PCM uses to control spark advance. To provide optimum driveability and emissions, the PCM monitors input signals from the following components in calculating ignition spark timing:
• The ignition control module (ICM)
• The throttle position (TP) sensor
• The engine coolant temperature (ECT) sensor
• The mass air flow (MAF) sensor
• The intake air temperature (IAT) sensor
• The vehicle speed sensor (VSS)
• The transmission gear position or range information sensors
• The engine knock sensors (KS)
• The following describes the PCM to ICM circuits:
• Low resolution engine speed, 3X reference-PCM input-From the ICM, the PCM uses this signal to calculate engine RPM and CKP. The PCM also uses the pulses on this circuit to initiate injector operation.
• Low reference-PCM input-this is a ground circuit for the digital RPM counter inside the PCM, but the wire is connected to engine ground only through the IC module. This circuit creates a common ground plane and assures there is no ground drop between the PCM and IC module.
• IC timing signal -PCM output-ICM controls spark timing while the engine is cranking, this is called bypass mode. Once the PCM receives 3X reference signals from the ICM, the PCM applies 5 volts to the IC timing signal circuit allowing the ICM to switch spark advance to PCM control.
• IC timing control-PCM output-The IC output circuitry of the PCM sends out timing signals to the ICM on this circuit. When in the Bypass Mode, the ICM grounds these signals. When in the IC Mode, the signals are sent to the ICM to control spark timing.
• Modes of operation Anytime the PCM does not apply 5 volts to the IC timing signal circuit, the ICM controls ignition by triggering each coil in the proper sequence at a pre-calibrated timing advance. This is called Bypass Mode ignition used during cranking or running below a certain RPM, or during a default mode due to a system failure.

When the PCM begins receiving 24X reference and 3X reference pulses, the PCM applies 5 volts to the IC timing signal circuit. This signals the IC module to allow the PCM to control the spark timing. This is IC Mode ignition. During IC Mode, the PCM compensates for all driving conditions. If the IC mode changes due to a system fault, the system will stay in default until the ignition is cycled OFF/ON, or the fault is no longer present. Diagnostic trouble codes are available to accurately diagnose the ignition system with a scan tool.


The stuff in red seems to fit your problem to a "T"

 

Hmm thanks, I got the no 5/2 problem to work now, but its throwing the P0336 code, meaning it needs to be relearned. I have a regular scanner, but not one that can do the CKP Relearn like a TECH-II does.

CKP Variation Learn

It says "CKP variation is only relearned with a scan tool. It does not relearn “by itself.”" so thats where I'm stuck at for now. As not only was the PCM replaced, but so was both CKPs and the Cam sensor too.

Also, I meant the ICM not the ECU in my last post.

Probably won't be able to get back to it till sun, as we are frozen in all week. *sigh*

 

hello;
many thanks to burhead1 for posting all this information on ignition
we saw that his posts were interesting but then we learn something.
the goal is how modules communicate attempt to analyze the defects whether or not DTC.

we understand better how 7x cpk "bootstraps" commands to the ICM.
the signal shape would be interesting. So we have the seventh slot that would give the TDC position of two companions cylinders during the low resolution engine speed signal.

I am very surprised that provides the link: CKP Variation Learn.
On my venture in 2001, which did not want to start following a transponder problem, I changed PCM, BCM and the whole steering column with key and radio. These pieces came from a venture gearbox failure. After these changes, the venture01 will restart perfectly and without DTC.
this contradicts CKP variation Learn or this applies to which vehicles?
Or I was very very lucky?

 

I'm not quite sure myself. I've seen different things, but I guess yours is older than whenever it started.

I'm not sure MINE needs it really either, but if it keeps throwing that code, I probably do.

But I won't be able to start it till sunday, so I just have to keep looking for cheap options.

Once I can let it run for a bit, and finish coolant, and change the transmission fluid and filter, I can take it to a mechanic next week. (seems the scan tools that can do this job are out of my budget)

Thanks all, and hopefully all this info people gave will help others!