IdahoElkHunter
Always Learning
Demographics: tell us about your truck and your ambient conditions:
- Year: 1993
- Truck model and class (ie: c2500) GMC K2500 extended cab
- Automatic or Standard Auto
- Mileage: (indicate miles or km) 157000
Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) Heath Wastegate mod- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? Turbo
- Ambient outside temp: (indicate *C or *F) 80F
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) Don't Know??
What fuel additives are you using? none
- Where are you located? Boise, Idaho
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter Just cleaned...K&N-
Fuel filter changed 6 months ago
- CDR Valve? never
- Coolant – last flushed/replaced at 100K miles
- Oil – synthetic/regular, changed at every 3K miles, Rotella
- Batteries – state of charge, (matched set) replaced at Replaced one 2 weeks ago, they match, full charge-
Battery cables and grounds (removed, cleaned and tightened): Yes, when replaced battery -
Glow Plugs - how many miles on them? 20K
What type? AC Delco
- Injectors - last changed at never
History: (Describe how the problem first appeared.)
- What were you doing when it happened? Driving to work ~ 6:30am outside air temp was about 55F, speed between 45 and 55 mph-
How was the truck running fine before this problem appeared? Fine, the tranny shifts slightly rough.-
Has this problem ever happened before? No- Describe any related factors that might be part of the problem. I get a flashing code 12 more than 3 times, book calls out engine speed sensor but I can't find it only a vehicle speed sensor on the transfer case and I did replace it.- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) ____ And? Code 12
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
1f] Does your glow plug light come on? Yes For how long? 8-9 sec
1g] Do you see smoke from the exhaust while cranking? No What color? ________
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? ____________
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? _________
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? ___________
3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) ___________
3b] Condition of Extension harness (if used) Vendor or Homemade? _________
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: ___________
3e] PMD Age: _____________
4] Stalling Issues
4a] Do you experience stalling only when hot? ____________
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) ______
4c] Does pouring cool water over the IP seem to help with restarting? _________
4d] Is stalling momentary (engine recovers)? Yes
4e] Does SES light come on when engine hiccups? Yes
4f] Does cruise control quit working when engine hiccups? never checked
4g] Does re-starting seem to reset engine, restoring cruise and power? _________
4h] Changes to dash lights or instruments during stalling events? Just SES comes on]
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? no
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? no
5d] Excessive white smoke from exhaust on cold start?no
5e] Excessive black smoke from exhaust under hard acceleration? no
6] Performance Issues
6a] Do you have gauges? a boost gauge
6b] Maximum boost under load? 10 - 11 PSI
6c] Have you added a performance PCM (reflash) or Chip? NO
6d] Have you changed exhaust / downpipe / crossover? yes, mandrel bent with 4" exhaust6e]
Wastegate – mechanical or vacuum? mechanical
7] Temperature-related Issues:
7a] Single or dual thermostats? single
7b] Have you replaced them lately? No Manufacturer of replacements? don't remember
7c] Have you pulled and cleaned Radiator and coolers lately? no
7d] Have you replaced the fan clutch? No Manufacturer of replacement? ________
7e] (winter) Have you tested your antifreeze? No
When driving along to work and after about 2 miles on the freeway my truck seems to cutout for 1/2 second, the SES light comes on, RPM's drop, and it does it 5 -6 times. If I reduce the speed it is ok. Like I said above, I get a code 12 flashing. The book says it is not an error but it is flashing more than 3 times. Once the truck is warmed up it seems to be fine. Any help would be greatly appreciated. Thank you!
- Year: 1993
- Truck model and class (ie: c2500) GMC K2500 extended cab
- Automatic or Standard Auto
- Mileage: (indicate miles or km) 157000
Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) Heath Wastegate mod- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? Turbo
- Ambient outside temp: (indicate *C or *F) 80F
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) Don't Know??
What fuel additives are you using? none
- Where are you located? Boise, Idaho
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter Just cleaned...K&N-
Fuel filter changed 6 months ago
- CDR Valve? never
- Coolant – last flushed/replaced at 100K miles
- Oil – synthetic/regular, changed at every 3K miles, Rotella
- Batteries – state of charge, (matched set) replaced at Replaced one 2 weeks ago, they match, full charge-
Battery cables and grounds (removed, cleaned and tightened): Yes, when replaced battery -
Glow Plugs - how many miles on them? 20K
What type? AC Delco
- Injectors - last changed at never
History: (Describe how the problem first appeared.)
- What were you doing when it happened? Driving to work ~ 6:30am outside air temp was about 55F, speed between 45 and 55 mph-
How was the truck running fine before this problem appeared? Fine, the tranny shifts slightly rough.-
Has this problem ever happened before? No- Describe any related factors that might be part of the problem. I get a flashing code 12 more than 3 times, book calls out engine speed sensor but I can't find it only a vehicle speed sensor on the transfer case and I did replace it.- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) ____ And? Code 12
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
1f] Does your glow plug light come on? Yes For how long? 8-9 sec
1g] Do you see smoke from the exhaust while cranking? No What color? ________
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? ____________
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? _________
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? ___________
3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) ___________
3b] Condition of Extension harness (if used) Vendor or Homemade? _________
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: ___________
3e] PMD Age: _____________
4] Stalling Issues
4a] Do you experience stalling only when hot? ____________
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) ______
4c] Does pouring cool water over the IP seem to help with restarting? _________
4d] Is stalling momentary (engine recovers)? Yes
4e] Does SES light come on when engine hiccups? Yes
4f] Does cruise control quit working when engine hiccups? never checked
4g] Does re-starting seem to reset engine, restoring cruise and power? _________
4h] Changes to dash lights or instruments during stalling events? Just SES comes on]
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? no
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? no
5d] Excessive white smoke from exhaust on cold start?no
5e] Excessive black smoke from exhaust under hard acceleration? no
6] Performance Issues
6a] Do you have gauges? a boost gauge
6b] Maximum boost under load? 10 - 11 PSI
6c] Have you added a performance PCM (reflash) or Chip? NO
6d] Have you changed exhaust / downpipe / crossover? yes, mandrel bent with 4" exhaust6e]
Wastegate – mechanical or vacuum? mechanical
7] Temperature-related Issues:
7a] Single or dual thermostats? single
7b] Have you replaced them lately? No Manufacturer of replacements? don't remember
7c] Have you pulled and cleaned Radiator and coolers lately? no
7d] Have you replaced the fan clutch? No Manufacturer of replacement? ________
7e] (winter) Have you tested your antifreeze? No
When driving along to work and after about 2 miles on the freeway my truck seems to cutout for 1/2 second, the SES light comes on, RPM's drop, and it does it 5 -6 times. If I reduce the speed it is ok. Like I said above, I get a code 12 flashing. The book says it is not an error but it is flashing more than 3 times. Once the truck is warmed up it seems to be fine. Any help would be greatly appreciated. Thank you!