First off, thank you guys for putting together a great site!
I Rececntly aquired a 1995 6.5T suburban with auto. I'm having trouble with it randomly shutting down and missing/fish-bitting on me. The problem seems to be getting worse. I'm suspecting the PMD/FSD is to blaim but I don't want to overlook a "cheaper" repair -(OPS, Fuel pickup, etc.)
I noticed the truck will sputter sometimes when I step on it, Can this be a characteristic of the PMD faulty? or does a PMD usually totally shut you down and I have other fuel issues?
the PMD was replaced only 20K miles ago by the previous owner and is located on FSD heatsink on the intake manifold. Do they go bad that often? The old PMD is still mounted to the Pump.
I have not tested the Fuel pick up or OPS (oil pressure switch), cleaned the tank sock, or messed with the fuel filter or pump. I just wanted to see what you guys think to cut my troubleshooting time down as many of you seem to be 6.5 pros. maybe you can save me some time.
If I do need a new PMD which is the best one to get? Standyne? heath? I allready have a FSD heatsink but I will need to make or buy a ext. cable and driver. Is their anything I should consider for future performance upgrades concerning a new PMD? resistor?
6.5 Engine Diagnostic Troubleshooting Checklist
Problem: Explain your problem in concise language (ie: Cranks but won’t fire). ___________Random stall, chugging, sometimes won't start. sometimes 10min later it will start and run with out problem.
Demographics: tell us about your truck and your ambient conditions:
- Year: ___1995___
- Truck model and class (ie: c2500) 2500
- Automatic or Standard _____auto_____
- Mileage: (indicate miles or km) ____175K_____
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) _PMD, IP, head gaskets, OPS__________
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? ________F? it has turbo______
- Ambient outside temp: (indicate *C or *F) _____20*F_____
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) ____#2_____
- What fuel additives are you using? _____winter stuff at the pump______
- Where are you located? _____Wisconsin________
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter ____3 mo. ago_____
- Fuel filter _____10/09____
- CDR Valve? ___?______
- Coolant – last flushed/replaced at ______?_______
- Oil – synthetic/regular, changed at _____Mobil 1 5W40______
- Batteries – state of charge, (matched set) replaced at ______2006 good yet_______
- Battery cables and grounds (removed, cleaned and tightened): _______good_______
- Glow Plugs - how many miles on them? _____8 60K____ What type? ______AC Delco_______
- Injectors - last changed at _______?________
History: (Describe how the problem first appeared.)
- What were you doing when it happened? _______driving_______
- How was the truck running fine before this problem appeared? ______yes_______
- Has this problem ever happened before? ________yes_______________
- Describe any related factors that might be part of the problem. _______changed oil cooler lines and oil recently and problem seemed to get worse, coinsidence? but problem was happening before_______
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) __Y__ And? _____manually with Jumper wire, seems to repeat 35, but it will repeat it more than 3 times___
Diagnostics:
1] Starting:
1a] Does the engine start? ____yes_____
1b] Does the engine crank over? ___yes_____
1c] Are your batteries fully charged? ___yes______
1d] Have you removed, cleaned, and tightened all battery connections? ____yes____
1e] Does your Wait to Start light come on for a time? How long? ___no?______
1f] Does your glow plug light come on? ____yes_____ For how long? ___ave. 3 sec.______
1g] Do you see smoke from the exhaust while cranking? What color? ___when it doesn't start no, when it will yes bluish_____
1h] Does the Service Engine Light Glow during Start/bulb check? ____yes____
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? _____yes_______
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? ____havn't tried yet_____
2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)? ___________
2d] Loosen an injector line and crank the engine - does fuel come out? _________
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? _____yes______
3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) _____intake______
3b] Condition of Extension harness (if used) Vendor or Homemade? _____vendor good____
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. ____seens good_____
3d] PMD Make: _____Standyne______
3e] PMD Age: ______2years old_______
4] Stalling Issues
4a] Do you experience stalling only when hot? ____no________
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) ___no___
4c] Does pouring cool water over the IP seem to help with restarting? ____haven't tried_____
4d] Is stalling momentary (engine recovers)? ___sometimes______
4e] Does SES light come on when engine hiccups? ____yes_____
4f] Does cruise control quit working when engine hiccups? _____yes______
4g] Does re-starting seem to reset engine, restoring cruise and power? ____yes_____
4h] Changes to dash lights or instruments during stalling events? _____?______
5] Running Issues
5a] On cold start, does upper rad hose get hard before engine warms up? ___?____
5b] Any bubbles or oil film in coolant overflow tank? ___?____
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? ____?______
5d] Excessive white smoke from exhaust on cold start? ___?______
5e] Excessive black smoke from exhaust under hard acceleration? _____no_____
6] Performance Issues
6a] Do you have gauges (boost, EGT) ? ____no_______
6b] Maximum boost under load? _____?_______
6c] Have you added a performance PCM (reflash) or Chip? _____no_________
6d] Have you changed exhaust / downpipe / crossover? _______no_________
6e] Wastegate – mechanical or vacuum (OEM)? _____oem_________
7] Temperature-related Issues:
7a] Single or dual thermostats? _____?_______
7b] Have you replaced them lately? Manufacturer of replacements? _____no____
7c] Have you pulled and cleaned Radiator and coolers lately? _____no_______
7d] Have you replaced the fan clutch? Manufacturer of replacement? ___no_____
7e] (winter) Have you tested your antifreeze? Good to what temp? _____no_____
7f] (winter) Are you using a winter grille cover? ____no_______
List and describe any other factors which are not addressed in this checklist. We can’t see, hear, smell, or touch your truck, so the more descriptive information you can give, the more likely it is that somebody can assist you.
when engine stalls while driving it will shuf off the cruise if its on, and MIL will turn on sometimes stays on for minuets but usually turns off again soon.
Any help is much appreciated, thank you very much.
ps I have picture of my recect PMD setup if that helps in anyway
I Rececntly aquired a 1995 6.5T suburban with auto. I'm having trouble with it randomly shutting down and missing/fish-bitting on me. The problem seems to be getting worse. I'm suspecting the PMD/FSD is to blaim but I don't want to overlook a "cheaper" repair -(OPS, Fuel pickup, etc.)
I noticed the truck will sputter sometimes when I step on it, Can this be a characteristic of the PMD faulty? or does a PMD usually totally shut you down and I have other fuel issues?
the PMD was replaced only 20K miles ago by the previous owner and is located on FSD heatsink on the intake manifold. Do they go bad that often? The old PMD is still mounted to the Pump.
I have not tested the Fuel pick up or OPS (oil pressure switch), cleaned the tank sock, or messed with the fuel filter or pump. I just wanted to see what you guys think to cut my troubleshooting time down as many of you seem to be 6.5 pros. maybe you can save me some time.
If I do need a new PMD which is the best one to get? Standyne? heath? I allready have a FSD heatsink but I will need to make or buy a ext. cable and driver. Is their anything I should consider for future performance upgrades concerning a new PMD? resistor?
6.5 Engine Diagnostic Troubleshooting Checklist
Problem: Explain your problem in concise language (ie: Cranks but won’t fire). ___________Random stall, chugging, sometimes won't start. sometimes 10min later it will start and run with out problem.
Demographics: tell us about your truck and your ambient conditions:
- Year: ___1995___
- Truck model and class (ie: c2500) 2500
- Automatic or Standard _____auto_____
- Mileage: (indicate miles or km) ____175K_____
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) _PMD, IP, head gaskets, OPS__________
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? ________F? it has turbo______
- Ambient outside temp: (indicate *C or *F) _____20*F_____
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) ____#2_____
- What fuel additives are you using? _____winter stuff at the pump______
- Where are you located? _____Wisconsin________
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter ____3 mo. ago_____
- Fuel filter _____10/09____
- CDR Valve? ___?______
- Coolant – last flushed/replaced at ______?_______
- Oil – synthetic/regular, changed at _____Mobil 1 5W40______
- Batteries – state of charge, (matched set) replaced at ______2006 good yet_______
- Battery cables and grounds (removed, cleaned and tightened): _______good_______
- Glow Plugs - how many miles on them? _____8 60K____ What type? ______AC Delco_______
- Injectors - last changed at _______?________
History: (Describe how the problem first appeared.)
- What were you doing when it happened? _______driving_______
- How was the truck running fine before this problem appeared? ______yes_______
- Has this problem ever happened before? ________yes_______________
- Describe any related factors that might be part of the problem. _______changed oil cooler lines and oil recently and problem seemed to get worse, coinsidence? but problem was happening before_______
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) __Y__ And? _____manually with Jumper wire, seems to repeat 35, but it will repeat it more than 3 times___
Diagnostics:
1] Starting:
1a] Does the engine start? ____yes_____
1b] Does the engine crank over? ___yes_____
1c] Are your batteries fully charged? ___yes______
1d] Have you removed, cleaned, and tightened all battery connections? ____yes____
1e] Does your Wait to Start light come on for a time? How long? ___no?______
1f] Does your glow plug light come on? ____yes_____ For how long? ___ave. 3 sec.______
1g] Do you see smoke from the exhaust while cranking? What color? ___when it doesn't start no, when it will yes bluish_____
1h] Does the Service Engine Light Glow during Start/bulb check? ____yes____
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? _____yes_______
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? ____havn't tried yet_____
2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)? ___________
2d] Loosen an injector line and crank the engine - does fuel come out? _________
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? _____yes______
3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) _____intake______
3b] Condition of Extension harness (if used) Vendor or Homemade? _____vendor good____
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. ____seens good_____
3d] PMD Make: _____Standyne______
3e] PMD Age: ______2years old_______
4] Stalling Issues
4a] Do you experience stalling only when hot? ____no________
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) ___no___
4c] Does pouring cool water over the IP seem to help with restarting? ____haven't tried_____
4d] Is stalling momentary (engine recovers)? ___sometimes______
4e] Does SES light come on when engine hiccups? ____yes_____
4f] Does cruise control quit working when engine hiccups? _____yes______
4g] Does re-starting seem to reset engine, restoring cruise and power? ____yes_____
4h] Changes to dash lights or instruments during stalling events? _____?______
5] Running Issues
5a] On cold start, does upper rad hose get hard before engine warms up? ___?____
5b] Any bubbles or oil film in coolant overflow tank? ___?____
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? ____?______
5d] Excessive white smoke from exhaust on cold start? ___?______
5e] Excessive black smoke from exhaust under hard acceleration? _____no_____
6] Performance Issues
6a] Do you have gauges (boost, EGT) ? ____no_______
6b] Maximum boost under load? _____?_______
6c] Have you added a performance PCM (reflash) or Chip? _____no_________
6d] Have you changed exhaust / downpipe / crossover? _______no_________
6e] Wastegate – mechanical or vacuum (OEM)? _____oem_________
7] Temperature-related Issues:
7a] Single or dual thermostats? _____?_______
7b] Have you replaced them lately? Manufacturer of replacements? _____no____
7c] Have you pulled and cleaned Radiator and coolers lately? _____no_______
7d] Have you replaced the fan clutch? Manufacturer of replacement? ___no_____
7e] (winter) Have you tested your antifreeze? Good to what temp? _____no_____
7f] (winter) Are you using a winter grille cover? ____no_______
List and describe any other factors which are not addressed in this checklist. We can’t see, hear, smell, or touch your truck, so the more descriptive information you can give, the more likely it is that somebody can assist you.
when engine stalls while driving it will shuf off the cruise if its on, and MIL will turn on sometimes stays on for minuets but usually turns off again soon.
Any help is much appreciated, thank you very much.
ps I have picture of my recect PMD setup if that helps in anyway
