Need help geting (ses) codes 17,18,35,36 stuck in limp mode
 

Have a 95 gmc3500 with the 6.5 im all new to the diesels and I need help I'm geting codes 17 high resolution sensor fault 18 pump cam reference pulse error 35 injector pulse width error & 36 injector pulse width error-long response. I don't even know where to start looking at things i replaced all the grounds air filter flue filter oil it has the relocated pmd and checked all the wires but the (ses) still on but sum times it goes of truck will run great till I get really get on it then it skips and the light comes back ok king it in to a limp mode it's a 5 speed and I can still rev over 2500rpm and I can go over 65 70 mph please if any one can help tell me what i should start with :scare2:

fuel starvation,, most likely..

lets start with this... report back..

1994 and up 6.5 owners should have a good spare PMD on hand and where the PMD and good heat sync are relocated to are just as important if you don't have the 6ft extension harness get one and move it to behind the front licence plate between the nostrils as they are called, this is the best place to avoid heat soak in a already sensitive part.

Oh welcome to D.B.

Not saying its not a valid diagnostic aid, or you shouldnt have a known good spare near by but..
After nearly 20 years, 400,000 miles. The PMD Goblin still eludes me and Ive witnessed as many PCM (GM's friendly) Ghost be routinely MISTAKEN for just another passing PMD goblin..

Before you rush out and purchase what amounts to "A Leap Of Faith", do some thorough diagnostics first starting with those most "Important Preliminary Checks"..

Never guess so I'll tell you where my known good spare (test) PMD came from.. Off my last misdiagnosed IP that had 198,000 miles on it.

These IPs and PMDs are far more robust than is widely perceived.

The PMD relocating process helps REESTABLISH the faulty connections and/or reduce the amount of resistance most likely built up in the aging PMD/FS harness that Stanadyne now includes with the latest new improved "golden" PMDs. Now you know why..

Frankly, the PMD Goblin was most likely a figment of some GMCorp exec's imagination in an attempt to divert attention away from authorized service centers and there acting agents who FAILED to receive the proper training necessary to avoid repeated misdiagnosis and after a time, Stanadyne refused to continue replacing good IPs for GM techs costly misdiagnosis... Enter the Goblin..
Bullshit worked too, warranty is long expired and independent stealers are still regurgitating these horror stories for there own financial gain..
Stanadyne is NO longer obligated to do it GMs way hence golden harness update which likely contributed to as many misdiagnosis as the forementioned goblin did.. all im saying

So I replaced the lifter pump and the ops sensor trying to fix the flue problem. but when I open the t valve I get a stead amont of fuel coming out to then close it shut the truck down and turn back on to have no (ses) light sum times tho. If not on I run and drive a truck sum times kicks back on driving sum times only after I shut it down and turn it back on could it be a bad injector pump

Could be, but not likely.. Avoid beginning the diagnostic process with preconceived notions and follow proper procedures. Avoid jumping around, dont skip a step or section just cause its labor intensive and/or you checked/fixed/repaired/replaced it just last week or yesterday.. CHECK IT, THEN CHECK IT ALL AGAIN THOROUGHLY..

If your only going thru the motions, dont bother.. Just buy an IP and be done with it, maybe.


The EFI 6.5L Turbo Diesel is NOT just an "other" diesel and most proven diagnostics methods often employed on other diesels should not be applied to the 6.5.

New Lift Pump and OPS....
Did you drop, clean and inspect the fuel tank?
Did you clean, inspect and test the fuel sender?
Did you also replace the fuel strainer while the Fuel sender was accessible?
Did you replace the o-rings at the lift pump and fuel sender fuel line connections?
If you answered "NO" to any of those questions, you only performed the easy portion of the lift pump replacement procedure.
Simply having our lift pump "conveniently" mounted on the frame vs inside the tank doesnt mean we (diesel models) dont have to follow the same exact and PROPER PROCEDURES as our gasoline counterparts....
A restricted fuel strainer can quickly damage a new lift pump due to cavitating. Thats why most aftermarket fuel pump manufacturers (Carter, Walbro, etc) require that a new strainer be installed ANYTIME the lift pump is replaced to avoid voiding the warranty..

Lift Pumps dont suck, they blow. If the natural fuel flow from the tank cant keep up with the lift pump demands, cavitation can occur resulting in a lift pump that quickly overheats as it dry humps itself to a premature death.



You need to start with a most thorough underhood inspection aka "Important Preliminary Checks."
Often most driveability complaints can be resolved during this initial but critical step of the process.. If you miss s'it here, s'it may lead to a costly misdiagnosis later as all DTC diagnostic charts assumes all that s'it is good too...
Bottom line. Ensure there are no faulty wiring or harness(s), no lose or corroded electrical connections, no split, cracked and/or deteriorated fuel/vacuum hoses, no blown fuses, and the electrical, starting and charging systems are 100%.


You also need to do an On Board Diagnostic (OBD) System Check (attached), and check for DTCs. If you havent a scan tool, use the "OR JUMP DATA LINK CONNECTOR TERMINAL "B" to "A" outlined in step 3.. Are you familiar with how the "SES" lamp flashing out present/stored DTCs? One awesome advantage to owning an OBD1 model, a simple paperclip is all thats needed to check for and clear DTCs..

Report back any DTCs found, I suspect there will be one or more...
Perform the Fuel Pump Relay Circuit Diagnostics I posted (attached) above.

Give me a bit. I'll include those lengthy Fuel Supply System Checks (next post) noone bothers to do until after theyve replaced a perfectly good but misdiagnosed IP simply because they skipped over 'em cause they didnt see any obvious fuel leaks as if expecting a neon sign flashing "FIX LEAK HERE."
Fuel Leaks and air leaks are not one and the same, they are not always found together. Infact, its possible, very likely to have an air leak thats not leaking fuel, not so much as exhibiting a wet spot. If it were only that easy..
Checking for air leaks requires far more than a "look see" or quick "sniff test."
Air leaks can also occur when the vehicle is parked for extended periods such as while at work, overnight, or over the wekend or longer.... This typically creates Hard Start, No Start, Excessive Smoke during cold engine start up, Starts up, then dies, etc etc...

When was the last time all the steel lines were inspected, and the rubber fuel lines (both supply and return system) replaced?
They are supposed to be inspected annually and repaired/replaced as needed. Rubber fuel lines should be replaced at least once a decade regardless..
Same for the Fuel Filter Manager (FFM) housing. The fuel heater is a known trouble spot and should be tested after a decade or two of reliable service. The FFM also needs to removed, cleaned, inspected, rebuilt, and/or replaced at least once a decade to avoid the ever present airheads. Some fuel filters, the fuel heater and the WIF sensor o-rings are known to deteriorate, drip fuel and/or be the source of undiagnosed air leaks..



Air is the EFI 6.5s Kryptonite..
Grungy Grounds, its Nemesis..


Hopefully, BRB with those Fuel System Checks.
Good Luck..

Fuel Contamination Inspection and Cleaning
Note: This procedure checks for the presence of water and gasoline in diesel fuel that may cause injection pump and nozzle damage.
1. Remove the fuel filter element and inspect it:
• If water, gasoline or fungi/bacteria are not present, end the inspection.
• If water or fungi/bacteria are present, go to step 2.
• If gasoline is present, go to step 3.
2. Clean water from the fuel system in these steps:
A. Disconnect the batteries.
B. Drain the fuel tank.
C. Remove the fuel tank.
D. Remove the fuel pick-up/sending unit.
E. Inspect the fuel tank and fuel pick-up/sending unit for rust, fungi or bacteria:
• If no rust is present, clean the inside of the fuel tank and fuel pick-up/sending unit with hot water, then dry them with compressed air.
• If rust is present, replace the parts.
F. Disconnect the ends of the following lines:
• Lift pump suction
• Lift pump pressure
• Fuel filter outlet
• Fuel filter drain
• Fuel return
G. Inspect each of the lines and replace any rusted pipes.
H. Dry the inside of each line with low-pressure air.
I. Clean the inside of the fuel filter housing and dry it with compressed air.
J. Disconnect the electrical connector for the fuel shut-off solenoid in the injection pump.
K. Install a new fuel filter element.
L. Install the fuel pick-up/sending unit and fuel tank (add clean diesel fuel to 1/4 full).
M. Connect the following lines:
• Lift pump suction (both ends)
• Lift pump pressure (both ends)
• Fuel filter drain
• Fuel return (at injection pump)
N. Connect the fuel filter outlet and the fuel return line at the pick-up/sending unit to hoses that flow to metal containers.
O. Connect the batteries and crank the engine until clean fuel flows from the fuel filter outlet into a metal container (see Figure 7-59):
• Allow a maximum of 15 seconds cranking time, followed by 1 minute of cranking motor cooling time.
P. Connect the hose from the fuel filter outlet to the injection pump inlet.
Q. Open each injection line at its nozzle end and crank the engine until clean fuel flows from it:
• Use two wrenches when loosening the injection line fittings.
• Allow a maximum of 15 seconds cranking time, followed by 1 minute of cranking motor cooling time.
R. Tighten each injection line fitting at its nozzle:
• Use two wrenches when tightening the injection line fittings.
S. Remove the electrical connector for the fast idle/cold advance temperature switch and jumper its wiring harness terminals with an insulated wire.
T. Connect the electrical connector for the fuel shut-off solenoid in the injection pump.
U. Start and run the engine for 15 minutes while fuel flows from the fuel return line into a metal container (see Figure 7-60).
V. Stop the engine.
W. Connect the fuel return hose to the fuel pick-up/sending unit.
X. Remove the jumper wire and install the electrical connector for the fast idle/cold advance temperature switch.
Y. Clean the engine of fuel spillage.
Z. Fill the fuel tank and add a biocide, if needed.
3. Clean gasoline from the fuel system in these steps:
A. Determine a procedure:
• If the engine runs, follow steps B, C, J and K.
• If the engine does not run, begin at step C.
B. Drain the fuel tank.
C. Fill the fuel tank.
D. Disconnect the electrical connector for the fuel shut-off solenoid in the injection pump.
E. Remove the fuel filter outlet and connect it to a hose that flows to a metal container.
F. Crank the engine until clean fuel flows from the fuel filter outlet into a metal container:
• Allow a maximum of 15 seconds cranking time, followed by 1 minute of cranking motor cooling time
G. Connect the hose from the fuel filter outlet to the injection pump inlet.
H. Remove the electrical connector for the fast idle/cold advance temperature switch and jumper its terminals with an insulated wire.
I. Connect the electrical connector for the fuel shut-off solenoid in the injection pump.
J. Start and run the engine for 15 minutes.
K. Stop the engine.
L. Remove the jumper wire and install the electrical connector for the fast idle/cold advance temperature switch.
M. Clean the engine of fuel spillage.


Fuel-Specific Gravity Check
Note: The hydrometer fuel quality tester provides a general indication of fuel quality and should not be considered scientifically accurate.
1. Drain the fuel filter housing by doing these things:
• Stop the engine.
• Place a container under the drain valve exit hose at the left front side of the engine.
• Open the drain valve.
• Start the engine and operate it at operating speed until clear fuel appears at the drain valve exit hose.
• Fill a 1 -liter (0.946-quart) container with a sample of clean fuel.
• Close the drain valve and stop the engine.
• Bring the fuel sample to 60° F (16° C).
2. Obtain a fuel quality hydrometer (special tool J 34352).
3. Fill the hydrometer with the fuel sample by doing these things:
• Squeeze the hydrometer bulb.
• Submerse the hydrometer tip into the sample.
• Release the bulb, allowing fuel to enter the glass tube until it floats the glass bulb inside the tube.
• Gently spin the hydrometer to relieve the surface tension of the fuel sample.
4. Read the scale on the glass bulb at the point where the top of the fuel sample contacts it (see Figure 7-61):
• If the top of the fuel sample is in the yellow part of the glass bulb scale (above the green part), suspect the presence of gasoline in the fuel.
• If the top of the fuel sample is in the green part of the glass bulb scale, the fuel has high quality (approximate cetane rating of 46 to 50).
• If the top of the fuel sample is in the yellow part of the glass bulb scale (below the green part), the fuel has moderate quality (approximate cetane rating of 41 to 45).
• If the top of the fuel sample is in the red part of the glass bulb scale, the fuel has low quality (approximate cetane rating of 38 to 40).



continued next post...

FUEL SUPPLY SYSTEM CHECKS
If the fuel supply system is not delivering enough fuel, or air is being drawn into the fuel injection system, driveability could be greatly effected or a "Cranks But Will Not Run" symptom could exist. If other diagnostics indicates, or if the fuel supply system is suspected of not delivering enough fuel or drawing air, it should be tested as follows:

!!Important!!!!
-- Air leaks or restrictions on the suction side of the fuel pump will seriously affect pump output.
-- Make sure there is sufficient fuel in the tank.
-- Check for leaks at ALL fuel connections from the fuel tank to the injection pump.
-- Tighten any loose connections.
-- With engine running, check all hoses and lines for flattening or kinks that would restrict fuel flow.


Lift Pump Flow Check
1. Disconnect the electrical connector for the engine shutoff solenoid at the injection pump.
2. Disconnect the pipe at the lift pump outlet fitting.
3. Install a hose at the lift pump outlet fitting and place a 1 liter/quart container at the hose to collect fuel.
4. Crank the engine and measure the amount of fuel :
-- If more than .24 ltrs (1/2 pint) in 15 seconds, refer to "Lift Pump Pressure Check" in this section.
-- If less than .24 ltrs (1/2 pint) in 15 seconds, refer to "Lift Pump Suction Line Check" in this section.


Lift Pump Suction Line Check
1. Remove the fuel tank cap and repeat the "Lift Pump Flow Check."
-- If more than .24 ltrs (1/2 pint) in 15 seconds, replace the defective fuel cap and refer to the "Lift Pump Pressure Check."
-- If less than .24 ltrs (1/2 pint) in 15 seconds, go to the next step.
2. Separate the lift pump suction line from the fuel sender.
3. Connect the suction line to a source of clean fuel, using an additional hose.
4. Repeat "Lift Pump Flow Check."
-- If flow is more than .24 ltrs (1/2 pint) in 15 seconds, remove the fuel sender and check it for restrictions.
-- If flow is less than .24 ltrs (1/2 pint) in 15 seconds, go to step 5.
5. Check lift pump suction line for restriction:
-- If restriction exist, repair it and recheck the lift pump flow.
-- If no restriction exist, replace the lift pump and recheck lift pump flow.
6. Attach the lift pump suction line to the fuel sender.


Lift Pump Pressure Test
1. Install a tee adaptor at the injection pump fuel inlet connection.
2. Connect a pressure gauge with a dial indication of 0 to 103kPa (0 to 15 psi) to the tee adaptor.
3. Run engine and measure fuel pressure.
-- If pressure is at least 3 psi or 27 kPa go to step 4.
-- If pressure is less than 3 psi or 27kPa, refer to Chart A-5 in SECTION 3 (Fuel Pump Relay Circuit Diagnosis) before replacing lift pump.
4. Remove pressure gauge and tee adaptor.
5. Connect outlet pipe at the lift pump outlet fitting.
6. Clean any fuel spillage.
7. Run the engine to check for fuel leakage.


Fuel System Air Leak Test
1. Install a transparent hose between the fuel manager/filter outlet and injection pump fuel inlet.
2. Start and idle the engine, observing the fuel for air bubbles.
-- If air bubbles are not present, stop the engine and go to step 6.
-- If air bubbles are present, stop the engine and go to step 3.
3. Check the lift pump suction line for air leakage:
-- Disconnect fuel pipe from the fuel sender and plug it.
-- Disconnect the fuel pipe from the lift pump, and install a hand held vacuum pump with gauge.
-- Apply vacuum to the fuel pipe and observe the gauge reading:
--- If vacuum does not drop, connect fuel pipe and go to step 4.
--- If vacuum drops, repair the air leak in the suction line and install the suction line pipe and hose.
4. Check the fuel sender for air leakage:
-- Remove the fuel tank.
Remove the fuel sender from the fuel tank, remove strainer and plug the bottom of the pickup tube.
-- Apply a vacuum to the upper end of the pickup tube, and observe the gauge reading.
--- If vacuum does not drop, install the fuel sender and fuel tank.
--- If vacuum drops, replace the fuel sender, install the fuel tank, connect the fuel pipe and go to step 5.
5. Start and run the engine, observing the fuel for air bubbles:
-- If air bubbles are present, stop engine and recheck steps 3 and 4.
-- If air bubbles are not present, stop the engine and go to step 6.
6. Remove the transparent hose and connect the hose of the fuel manager/filter outlet to the injection pump inlet fitting.
7. Disconnect the return hose from the injection pump.
8. Install a transparent hose between the injection pump and the hose of the return line.
9. Start and run the engine, observing the fuel for air bubbles:
NOTICE: It is OK to see a small stream of air bubbles on snap acceleration
-- If air bubbles are not present, go to step 10.
-- If air bubbles are present, replace the injection pump.
10. Stop the engine.
11. Remove the transparent hose and attach the fuel return hose at the injection pump.
12. Clean any fuel spillage.
13. Run engine and check for fuel leaks.

Following any "Fuel Supply System Check(s)" outlined aboved or otherwise, or any routine maint procedure(s) eg fuel filter change, or any repair(s) eg lift pump replacement and normal engine operation has been restored.. The last step of the process is to check for, make note of, and CLEAR DTC(s).

Would the truck still run with a bad ip tho and flick on and off codes Or could it just be a bad pmd. But it dosent have a stalling or a not starting problem and when light goes out truck starts faster and easyer it has 200,000 miles on just don't wanna waist money on havinf some one look at it for me

I cant answer that... Depends on the malfunction.


I do know that having an "mechanic" look at it will likely cost you a new IP, for starters.

Most "mechanics" are unfamiliar (clueless) with 6.5s. Very few mechanics ever received any, much less the proper training necessary to avoid very costly repeated misdiagnosis.

Unless you just want to support OJT at $100.00 an hour plus parts, I suggest you try and DIY...


good luck