Glagulator
03-24-2008, 01:49 PM
Hello fellow 6.5ers.
I'm getting an excedrine headache over this. I am hoping some of you pros might help me out.
I am trying to diagnose a slight miss on my wife,s 96 sub.
BEFORE replacing the parts listed in my sig. the burb ran smooth as glass, no miss.
Work was done to replace a failed IP and the other parts due to miles and improvement.
After the work was done the burb fired right up and has run as well as a new one, EXCEPT
While normally driving there is a very weak miss, that becomes more noticable when OD kicks in under slight accelleration or incline.
Under hard accelleration it seems to not miss or lack power.
The miss has not changed since the repairs, always there, always the same.
I can power brake the burb and feel the miss, maybe not driveline related.
No black smoke, very little or no white smoke when started cold.
I finally got a code for #3 cylinder imbalance, so I replaced that new injector with a good one and no change.
Compression - #1 - 410 #2 - 450
#3 - 450 #4 - 420
#5 - 420 #6 - need adapter, on it's way
#7 - 450 #8 - 450
Glow plugs all looked about the same.
When cranking over the engine with pmd unplugged it sounds nice and even, FWIW.
Also replaced the rocker arm retainers, although they were still soft and hard to remove.
There are no signs of cracked heads or block, no mixed fluids, runs cool, no leaks at all.
Fuel tank has been removed, was clean as new! Could not believe it.
Lift pump working fine. All grounds cleaned and accounted for.
New pmd mounted behind front bumper.
Inj. lines looked good and were not bent any during work.
Inj. lines are not touching each other or anything else they should not.
The wife has driven the burb over 3000 miles like this with no change.
No unusuall noises from the intake to indicate a valve problem.
After hours of searching and reading, the closest thing I could find was a truck with a cracked valve spring,
but he also had a noise in the intake.
The HB and pulley look good, have had that problem several times on other trucks, does not feel the same.
Timing is very close to spec.
Feels exactly like a weak cylinder, but comp test says not. (so far)
What am I overlooking?
Can the inj. pump cause a miss on one cylinder?
Any insight would be greatly appreciated. Thanks, Mike
0. Describe in detail the problem you are having. Please be as descriptive as possible.
1. Does the engine crank, or 'turn over'? yes
1a. Does the engine start and run? yes
1a1. If the engine does not start - Crack injector line (http://www.dieselplace.com/forum/showthread.php?p=2188140#post2188140): do you have fuel? Yes
1b. Do you have a Wait To Start Light & the amount of time (seconds) lit. yes, 5-6 sec
1c. Ambient Condition (temperature outside indicate F or C) _75 f____ °
1d. Engine Cranking speed (if you have an accurate tachometer). normal
1e. Are you experiencing stalling? no
1f. If Stalling, describe (upon startup only, down the road, hit a bump etc)
1g. If Stalling, do you notice loss of dash or instruments?
-note if experiencing stalling,you must indicate PMD location in #24.1.1 Lift pump test (http://dieselplace.com/forum/showthread.php?t=39350)- describe results
2. Service Engine Light while running?- off
2a. Service Engine light does glow during start/cranking/bulb check: Yes
3. Model year 1996
3a. Odometer reading 209,689 mi
3b. Miles on major engine components if been replaced approx 3,000 mi
3c. Indicate the model number on the Injection pump DS4 831 5521
4. Have you scanned for engine codes? yes
5. List exact results on engine codes- P0269 Cylinder 3 Balance System
6. Air Filter condition- new
7. Fuel filter condition- new
8. Condition of Battery terminal connections OK (removed, cleaned and tightened)
8a. Known condition and age of the batteries. new
8b. Are batteries of differing age or are they a matched set? matched
8c. Condition of Major Grounds- Done
9. Upon cold start, does the radiator hose get hard quickly? no
10. Upon cold start, do you have excessive white smoke? no
11. Do you have excessive cranking time before the engine starts? no, almost instant
12. Have you used the block heater, and does this effect engine starting? no
13. During hard acceleration, do you have excessive black smoke? no
14. Do you have any unusual exhaust smoke issues? no
15. Turbo check out. Set the TM to just a weak black smoke at full throt. Gauge is coming. Burb never sees
full throt. except when testing.
16. Do you have an EGR on the engine? F, no
17. Indicate if you know if. its a 2500HD.
18. Indicate fuel that you are using: #2 Diesel
18a. If running a VO - no
19. Are you using any fuel additives? Two stroke and standadyne
20. Please indicate geographic region you are in: South Texas
21. Do you have any service history available that might pertain to the problem you are having? no
22. Please indicate any modifications to the vehicle that might help us diagnose better. See my sig.
23. Upon unscrewing the fuel cap- no - Tank collapsed on vacation 3yrs ago, removed, repaired,
tiny vent hole in cap.
24. Location of PMD/FSD. remoted out of engine bay behind front bumper.
24a. If remote mounted, describe wiring harness. homemade, it's ok, I even tested the connections.
24b. Indicate the location and condition of the FSD/IP grounding wire. Stock location
25. Are ALL glow plugs in proper working order as per this thread? Yes, and they are new.
I'm getting an excedrine headache over this. I am hoping some of you pros might help me out.
I am trying to diagnose a slight miss on my wife,s 96 sub.
BEFORE replacing the parts listed in my sig. the burb ran smooth as glass, no miss.
Work was done to replace a failed IP and the other parts due to miles and improvement.
After the work was done the burb fired right up and has run as well as a new one, EXCEPT
While normally driving there is a very weak miss, that becomes more noticable when OD kicks in under slight accelleration or incline.
Under hard accelleration it seems to not miss or lack power.
The miss has not changed since the repairs, always there, always the same.
I can power brake the burb and feel the miss, maybe not driveline related.
No black smoke, very little or no white smoke when started cold.
I finally got a code for #3 cylinder imbalance, so I replaced that new injector with a good one and no change.
Compression - #1 - 410 #2 - 450
#3 - 450 #4 - 420
#5 - 420 #6 - need adapter, on it's way
#7 - 450 #8 - 450
Glow plugs all looked about the same.
When cranking over the engine with pmd unplugged it sounds nice and even, FWIW.
Also replaced the rocker arm retainers, although they were still soft and hard to remove.
There are no signs of cracked heads or block, no mixed fluids, runs cool, no leaks at all.
Fuel tank has been removed, was clean as new! Could not believe it.
Lift pump working fine. All grounds cleaned and accounted for.
New pmd mounted behind front bumper.
Inj. lines looked good and were not bent any during work.
Inj. lines are not touching each other or anything else they should not.
The wife has driven the burb over 3000 miles like this with no change.
No unusuall noises from the intake to indicate a valve problem.
After hours of searching and reading, the closest thing I could find was a truck with a cracked valve spring,
but he also had a noise in the intake.
The HB and pulley look good, have had that problem several times on other trucks, does not feel the same.
Timing is very close to spec.
Feels exactly like a weak cylinder, but comp test says not. (so far)
What am I overlooking?
Can the inj. pump cause a miss on one cylinder?
Any insight would be greatly appreciated. Thanks, Mike
0. Describe in detail the problem you are having. Please be as descriptive as possible.
1. Does the engine crank, or 'turn over'? yes
1a. Does the engine start and run? yes
1a1. If the engine does not start - Crack injector line (http://www.dieselplace.com/forum/showthread.php?p=2188140#post2188140): do you have fuel? Yes
1b. Do you have a Wait To Start Light & the amount of time (seconds) lit. yes, 5-6 sec
1c. Ambient Condition (temperature outside indicate F or C) _75 f____ °
1d. Engine Cranking speed (if you have an accurate tachometer). normal
1e. Are you experiencing stalling? no
1f. If Stalling, describe (upon startup only, down the road, hit a bump etc)
1g. If Stalling, do you notice loss of dash or instruments?
-note if experiencing stalling,you must indicate PMD location in #24.1.1 Lift pump test (http://dieselplace.com/forum/showthread.php?t=39350)- describe results
2. Service Engine Light while running?- off
2a. Service Engine light does glow during start/cranking/bulb check: Yes
3. Model year 1996
3a. Odometer reading 209,689 mi
3b. Miles on major engine components if been replaced approx 3,000 mi
3c. Indicate the model number on the Injection pump DS4 831 5521
4. Have you scanned for engine codes? yes
5. List exact results on engine codes- P0269 Cylinder 3 Balance System
6. Air Filter condition- new
7. Fuel filter condition- new
8. Condition of Battery terminal connections OK (removed, cleaned and tightened)
8a. Known condition and age of the batteries. new
8b. Are batteries of differing age or are they a matched set? matched
8c. Condition of Major Grounds- Done
9. Upon cold start, does the radiator hose get hard quickly? no
10. Upon cold start, do you have excessive white smoke? no
11. Do you have excessive cranking time before the engine starts? no, almost instant
12. Have you used the block heater, and does this effect engine starting? no
13. During hard acceleration, do you have excessive black smoke? no
14. Do you have any unusual exhaust smoke issues? no
15. Turbo check out. Set the TM to just a weak black smoke at full throt. Gauge is coming. Burb never sees
full throt. except when testing.
16. Do you have an EGR on the engine? F, no
17. Indicate if you know if. its a 2500HD.
18. Indicate fuel that you are using: #2 Diesel
18a. If running a VO - no
19. Are you using any fuel additives? Two stroke and standadyne
20. Please indicate geographic region you are in: South Texas
21. Do you have any service history available that might pertain to the problem you are having? no
22. Please indicate any modifications to the vehicle that might help us diagnose better. See my sig.
23. Upon unscrewing the fuel cap- no - Tank collapsed on vacation 3yrs ago, removed, repaired,
tiny vent hole in cap.
24. Location of PMD/FSD. remoted out of engine bay behind front bumper.
24a. If remote mounted, describe wiring harness. homemade, it's ok, I even tested the connections.
24b. Indicate the location and condition of the FSD/IP grounding wire. Stock location
25. Are ALL glow plugs in proper working order as per this thread? Yes, and they are new.