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Pete, GMC Mechanic
Category: GMC
Satisfied Customers: 29116
Experience:  GM training and dealer tech for 14+ years. Diagnostics
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I just bought gmc Savana 2000 with 6.5 diesel. It has PMD

Customer Question

I just bought gmc Savana 2000 with 6.5 diesel. It has PMD installed on the fender. Right now I can not start the van. It starts on 4 or 5 cylinders and quit firing like there is no fuel. No matter how long you crank it will no fire again. If you start cranking again it is the same - 4 or 5 cylinders start and quit. Inline fuel is working and supply enough fuel. Just to make sure I made direct power supply to the pump so pump can work constantly with ignition on. No codes except P1656. Try new PMD. I tried to disconnect optical sensor but I am not sure if I got right one - it had only 2 wires - should be 4? Also I do not know where is Crank sensor and how I can test it. Is there any way to test PMD? I am not sure that new one from the store is OK since I found some scratch marks on it.
Submitted: 1 year ago.
Category: GMC
Expert:  Pete replied 1 year ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.

If you can check and make sure there is no debris or contaminants in the fuel itself.In some cases if the fuel is contaminated with debris or a substance that isn't fuel like water the fuel pressure will be o.k. but the engine will not start or run properly when it does start.If this was already checked and found to be o.k. let me know so we can continue.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.Thanks Pete.

Customer: replied 1 year ago.
It is not fuel contamination. I changed fuel filter today, add some cetane booster to make start easier with no success. I changed 2 burned glow plugs, no effect to the engine. Engine catches firing on 4 or 5 cylinders to the moment that you want to stop cranking and engine stops like someone would turn of ignition. If you still cranking it takes about 4 seconds to initiate starts on 4 or 5 cylinders and cycle repeats again. There is plenty of smoke from tail pipe. It seams that computer cutting off the signal to the pump for some reason. I was told that sometimes it happens this when the coolant level is to low and engine would not start to prevent overheating. I just topped the level - no change. Do not know what to do. Is it the injection pump dead? - It is plenty of smoke though. No signal from the crank signal? Malfunction of main computer? I am running out of ideas. Still engine does not show codes except p1656. The only other lead is that security light is on. I was told that there is no chip on the key, so why the light is on? Is there any security - anti theft system on 2000 Savana? What the light means?
Expert:  Pete replied 1 year ago.

This model does use a security feature and it is actually part of the electronic ignition switch itself.From the electronic ignition switch there is a single or two wire sensor that seats into the top of the ignition cylinder housing.This is a plunger type sensor that the plunger is depressed with the correct key in the ignition and the ignition rotated.If this plunger breaks off (which is common) then the electronic ignition switch needs replaced.This needs checked to see if it is broken with this switch needing replaced to correct this fault here.

You can try this relearn below as this is the security relearn for this model.You can skip the steps of clearing out the fault codes as this isn't needed to do this relearn here.

REPROGRAMMING PROCEDURE The following is the Auto Learn Procedure: 1. Insure the ignition key is in the ON position. 2. Clear all Passlock(TM) Module and VCM/PCM DTCs. 3. Momentarily rotate the ignition key to the CRANK position (Do NOT start the vehicle), then release it to the RUN position (Do NOT key OFF in the process). 4. Wait 10 minutes. Observe the SECURITY indicator. Refer to the following list for the appropriate responses: ^ If the Passlock(TM) sensor was replaced the SECURITY indicator will flash for the 10 minutes duration. ^ If the Passlock(TM) Module was replaced, the SECURITY indicator will flash for a few seconds and then remain ON for the remainder of the 10 minutes duration. ^ If the VCM/PCM was replaced with a new programmed VCM/PCM and connected to the vehicle for the first time, the vehicle will start and this procedure may not be necessary. ^ If the replacement VCM/PCM was connected to any vehicle at any other time, even momentarily, the SECURITY indicator will flash for a few seconds and then remain ON for the 10 minutes duration. 5. The SECURITY indicator will transition from flashing to ON briefly to OFF after 10 minutes if remaining in the ignition ON position. 6. Turn the ignition switch to the OFF position and wait for 10 seconds. 7. Repeat steps 3-6 two more times. The new security code is ready to be communicated among the Passlock Sensor, Passlock Module and VCM/PCM. The new password ***** ***** on the next ignition lock cylinder cycle from OFF to CRANK to ON (start attempt).

Thanks Pete

Customer: replied 1 year ago.
I tried reprogramming procedure. The security lights it stay on all the time. It never flashes. Engine it is still not running. What is the solution?
Expert:  Pete replied 1 year ago.

O.k.,if you can remove the steering column covers especially the top cover behind the steering wheel and there should be a small plunger sensor that seats into the top of the ignition cylinder housing.There is a tab that you press inward on the side of the sensor to then rotate the sensor and remove it.See if the little plunger ball is worn off.If it is then the ignition switch itself needs replaced and will cause this here.It should look similar to this here.If you look at the small whitish sensor behind the pick in the diagram here this is the plunger that fails.

Thanks Pete