83GMCK2500
Active Member
Problem: Explain your problem in concise language
Throws engine codes 32 and 33 at unpredictable intervals (usually when traversing steep, unpaved terrain), and engine RPMs occasionally spike without touching the accelerator when manually switching gears and when braking or releasing the accelerator. Appears to be getting worse (at least the rpm-spiking does) with time.
Demographics: tell us about your truck and your ambient conditions:
- Year: 1995
- Truck model and class (ie: c2500): K1500
- Automatic or Standard: automatic
- Mileage: (indicate miles or km): 207,000 miles
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc): PMD, glowplugs, No. 9 resistor installed
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR?: S, turbo, EGR (I assume, since the codes indicate EGR failure)
- Ambient outside temp (indicate *C or *F): Variable. Usually above 10 C
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc): highway-approved diesel, occasionally 10% bio-blend
- What fuel additives are you using?: Cetane boost low-sulfur diesel fuel additive
- Where are you located?: northern intermountain region in USA, WA state
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter: Unknown, prior to 2005 would be most recent.
- Fuel filter: Changed 2007
- CDR Valve: Unknown
- Coolant – last flushed/replaced at: Unknown, prior to 2005 if at all. Truck still has dexcool in it, may be original.
- Oil – synthetic/regular, changed at: Regular, changed last at 201,000 miles
- Batteries – state of charge, (matched set) replaced at: Good charge, matched set, replaced 2008
- Battery cables and grounds (removed, cleaned and tightened): Clean
- Glow Plugs - how many miles on them?: Less than 10,000 miles. What type?: SSD, high-performance "instant heat".
- Injectors - last changed at: Unknown, prior to 2005 if at all.
History: (Describe how the problem first appeared.)
- What were you doing when it happened?: driving at variable speeds over steep, uneven, unpaved terrain
- How was the truck running fine before this problem appeared?: running fine
- Has this problem ever happened before?: happens regularly, engine high-revving "bucking" seems to be getting worse
- Describe any related factors that might be part of the problem.: codes thrown indicate an EGR/ECM failure. Altitude-dependent? Does not seem to be strongly corellated with altitude
- Have you checked for DTC (Diagnostic Trouble Codes)? Yes, Codes 32 & 33.
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?: No
1e] Does your Wait to Start light come on for a time? How long?: Yes, less than 8 seconds.
1f] Does your glow plug light come on? How long?: Yes, less than 8 seconds.
1g] Do you see smoke from the exhaust while cranking? What color?: Yes, black.
...
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? _________
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: New model from SSD, not Stanadyne.
3e] PMD Age: New last summer, so 1-yr old.
...
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?: 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 aftermarket gauges?: No
6b] Maximum boost under load?: unknown
6c] Have you added a performance PCM (reflash) or Chip?: Don't think so.
6d] Have you changed exhaust / downpipe / crossover?: No
6e] Wastegate – mechanical or vacuum?: Unknown
...
I edited out the sections that he did not answer. This is for a guy I know at school, he's been having the afore mentioned codes and problem occur more frequently and wanted to know what it might be. It is possible the truck has a PROM w/ +40HP tune in it, previous owner mentioned it though unverified.
Throws engine codes 32 and 33 at unpredictable intervals (usually when traversing steep, unpaved terrain), and engine RPMs occasionally spike without touching the accelerator when manually switching gears and when braking or releasing the accelerator. Appears to be getting worse (at least the rpm-spiking does) with time.
Demographics: tell us about your truck and your ambient conditions:
- Year: 1995
- Truck model and class (ie: c2500): K1500
- Automatic or Standard: automatic
- Mileage: (indicate miles or km): 207,000 miles
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc): PMD, glowplugs, No. 9 resistor installed
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR?: S, turbo, EGR (I assume, since the codes indicate EGR failure)
- Ambient outside temp (indicate *C or *F): Variable. Usually above 10 C
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc): highway-approved diesel, occasionally 10% bio-blend
- What fuel additives are you using?: Cetane boost low-sulfur diesel fuel additive
- Where are you located?: northern intermountain region in USA, WA state
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter: Unknown, prior to 2005 would be most recent.
- Fuel filter: Changed 2007
- CDR Valve: Unknown
- Coolant – last flushed/replaced at: Unknown, prior to 2005 if at all. Truck still has dexcool in it, may be original.
- Oil – synthetic/regular, changed at: Regular, changed last at 201,000 miles
- Batteries – state of charge, (matched set) replaced at: Good charge, matched set, replaced 2008
- Battery cables and grounds (removed, cleaned and tightened): Clean
- Glow Plugs - how many miles on them?: Less than 10,000 miles. What type?: SSD, high-performance "instant heat".
- Injectors - last changed at: Unknown, prior to 2005 if at all.
History: (Describe how the problem first appeared.)
- What were you doing when it happened?: driving at variable speeds over steep, uneven, unpaved terrain
- How was the truck running fine before this problem appeared?: running fine
- Has this problem ever happened before?: happens regularly, engine high-revving "bucking" seems to be getting worse
- Describe any related factors that might be part of the problem.: codes thrown indicate an EGR/ECM failure. Altitude-dependent? Does not seem to be strongly corellated with altitude
- Have you checked for DTC (Diagnostic Trouble Codes)? Yes, Codes 32 & 33.
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?: No
1e] Does your Wait to Start light come on for a time? How long?: Yes, less than 8 seconds.
1f] Does your glow plug light come on? How long?: Yes, less than 8 seconds.
1g] Do you see smoke from the exhaust while cranking? What color?: Yes, black.
...
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? _________
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: New model from SSD, not Stanadyne.
3e] PMD Age: New last summer, so 1-yr old.
...
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?: 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 aftermarket gauges?: No
6b] Maximum boost under load?: unknown
6c] Have you added a performance PCM (reflash) or Chip?: Don't think so.
6d] Have you changed exhaust / downpipe / crossover?: No
6e] Wastegate – mechanical or vacuum?: Unknown
...
I edited out the sections that he did not answer. This is for a guy I know at school, he's been having the afore mentioned codes and problem occur more frequently and wanted to know what it might be. It is possible the truck has a PROM w/ +40HP tune in it, previous owner mentioned it though unverified.
Last edited:
