VW_Lupo_TD
Active Member
Ok guys, would appreciate some input on following scenario.
wanted to post this here before I update my travel blog.
3-27: I get Diesel in Bardstown, KY, at a BP ~32gal + half a bottle of Stanadyne Performance Formula, as always and head down the backroads to cave city, all is fine, except for battery post - ran really low volts at night.
3-28: Battery post redone, almost 14V right away and started fine, got groceries and some around town driving.
3-29: en route to mammoth cave doing 30 mph at idle through the state park, the truck "stumbles" (for the lack of better words) as if it got cut off from fuel. Goes right back to normal and i park and shut it off after (as always) making sure EGT are under 300F.
after a 2 hour tour (it was awesome i am about to post pics and the story for the last couple of days) we get out and here it comes :
Problem: The Truck started extremely hard. It took me 3 cranks (each between 5-10 secs) to get it started. After it starts it more or less "stumbles" again for a few secs, then runs again just fine.
We let it run for about 10 mins, shut it off and try again - same thing. But once it ran it ran fine - so i make the call that we head for the Interstate and if we get there without trouble we head down south on I65 towards Nashville and see what happens. The only time it "stumbled" again was on the on ramp to I65 between 60 and 65 mph, but after that it ran normally all the way to nashville. We arrived at our destination and checked out a couple of campgrounds. after each time the truck started perfectly. But the first stop that took longer than 5 mins and it cooled of a bit, i almost could not get it started again and same stumbling issues after start and sometimes after starting to drive. Since i really did not want to shut it off but had to, i wanted to play it safe and I checked into a hotel as close to the Jim Reed Chevrolet dealership in Nashville and will try to be the first one there in the morning (especially driving there myself). I will omit my guesses to what it could be and wait for the pros to tell me what they think.
Demographics: tell us about your truck and your ambient conditions:
- Year: 1994
- Suburban 2500
- 4LE80
- ~203k miles
- IP was replaced by dealership under warranty at ~95k, i replaced FSD cooler with heath PMD Isolator at 160k, Heath GLE chip, Heath TM and rebuilt turbo, freshly done Injectors and glow plugs, also see attached xls
- Model: ‘‘F’ engine
- Ambient outside temp: it was colder days, but nothing freezing
- What fuel are you using? BP Diesel, the tank before that TA center
- What fuel additives are you using? Stanadyne Performance Formula, half a bottle per tank fill up
- Where are you located? right now a shitty hotel in nashville, TN
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter 3-14
- Fuel filter 3-14
- CDR Valve? before my time, still looks new though
- Coolant – last flushed/replaced at ~160k
- Oil – synthetic/regular, changed at 202155miles
- Batteries – state of charge, (matched set) replaced before my time
- Battery cables and grounds just removed, cleaned and tightened a couple of times
- Glow Plugs - how many miles on them? i would say less than 2k What type? Bosch Duraterm by heath
- Injectors - last changed at ~202500 also Bosch by heath (non HP)b
History: (Describe how the problem first appeared.)
- What were you doing when it happened? like i said "idling" at 30-35 mph
- How was the truck running fine before this problem appeared? just fine
- Has this problem ever happened before? nope, maybe kind of when FSD cooler / PMD started going, but not quite like it
- Have you checked for DTC (Diagnostic Trouble Codes)? NO
Diagnostics:
1] Starting:
1a] Does the engine start? Y, but barley
1b] Does the engine crank over? Y
1c] Are your batteries fully charged? they show 14V when it runs
1d] Have you removed, cleaned, and tightened all battery connections? the problematic one, yes
1e] Does your Wait to Start light come on for a time? How long? No clue. Will pay attention to that next time, but i think it does.
1f] Does your glow plug light come on? Y For how long? ~6 secs, then 5 times after that (GLE programming)
1g] Do you see smoke from the exhaust while cranking? What color? Not while cranking, but afterwards a little, as always before too
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? Y, brandnew on 3-15
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? Could not check that yet. but assume OK, since LP new.
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] Heath PMD Isolator
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: ___________
3e] PMD Age: 5-3-08, 187k mls
4] no stalling issues
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? __________
6] Performance Issues
6a] Do you have gauges? Y
6b] Maximum boost under load? 12PSI
6c] Have you added a performance PCM (reflash) or Chip? Heath GLE
6d] Have you changed exhaust / downpipe / crossover? Heath Super Flow and Hi Flow Cross over, almost brandnew
6e] Wastegate – mechanical or vacuum? Heath TM for GM8
7] Temperature-related Issues:
7a] Single or dual thermostats? Dual
7b] Have you replaced them lately? Manufacturer of replacements? nope, have been there for a while
7c] Have you pulled and cleaned Radiator and coolers lately? nope
7d] Have you replaced the fan clutch? nope
wanted to post this here before I update my travel blog.
3-27: I get Diesel in Bardstown, KY, at a BP ~32gal + half a bottle of Stanadyne Performance Formula, as always and head down the backroads to cave city, all is fine, except for battery post - ran really low volts at night.
3-28: Battery post redone, almost 14V right away and started fine, got groceries and some around town driving.
3-29: en route to mammoth cave doing 30 mph at idle through the state park, the truck "stumbles" (for the lack of better words) as if it got cut off from fuel. Goes right back to normal and i park and shut it off after (as always) making sure EGT are under 300F.
after a 2 hour tour (it was awesome i am about to post pics and the story for the last couple of days) we get out and here it comes :
Problem: The Truck started extremely hard. It took me 3 cranks (each between 5-10 secs) to get it started. After it starts it more or less "stumbles" again for a few secs, then runs again just fine.
We let it run for about 10 mins, shut it off and try again - same thing. But once it ran it ran fine - so i make the call that we head for the Interstate and if we get there without trouble we head down south on I65 towards Nashville and see what happens. The only time it "stumbled" again was on the on ramp to I65 between 60 and 65 mph, but after that it ran normally all the way to nashville. We arrived at our destination and checked out a couple of campgrounds. after each time the truck started perfectly. But the first stop that took longer than 5 mins and it cooled of a bit, i almost could not get it started again and same stumbling issues after start and sometimes after starting to drive. Since i really did not want to shut it off but had to, i wanted to play it safe and I checked into a hotel as close to the Jim Reed Chevrolet dealership in Nashville and will try to be the first one there in the morning (especially driving there myself). I will omit my guesses to what it could be and wait for the pros to tell me what they think.
Demographics: tell us about your truck and your ambient conditions:
- Year: 1994
- Suburban 2500
- 4LE80
- ~203k miles
- IP was replaced by dealership under warranty at ~95k, i replaced FSD cooler with heath PMD Isolator at 160k, Heath GLE chip, Heath TM and rebuilt turbo, freshly done Injectors and glow plugs, also see attached xls
- Model: ‘‘F’ engine
- Ambient outside temp: it was colder days, but nothing freezing
- What fuel are you using? BP Diesel, the tank before that TA center
- What fuel additives are you using? Stanadyne Performance Formula, half a bottle per tank fill up
- Where are you located? right now a shitty hotel in nashville, TN
General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter 3-14
- Fuel filter 3-14
- CDR Valve? before my time, still looks new though
- Coolant – last flushed/replaced at ~160k
- Oil – synthetic/regular, changed at 202155miles
- Batteries – state of charge, (matched set) replaced before my time
- Battery cables and grounds just removed, cleaned and tightened a couple of times
- Glow Plugs - how many miles on them? i would say less than 2k What type? Bosch Duraterm by heath
- Injectors - last changed at ~202500 also Bosch by heath (non HP)b
History: (Describe how the problem first appeared.)
- What were you doing when it happened? like i said "idling" at 30-35 mph
- How was the truck running fine before this problem appeared? just fine
- Has this problem ever happened before? nope, maybe kind of when FSD cooler / PMD started going, but not quite like it
- Have you checked for DTC (Diagnostic Trouble Codes)? NO
Diagnostics:
1] Starting:
1a] Does the engine start? Y, but barley
1b] Does the engine crank over? Y
1c] Are your batteries fully charged? they show 14V when it runs
1d] Have you removed, cleaned, and tightened all battery connections? the problematic one, yes
1e] Does your Wait to Start light come on for a time? How long? No clue. Will pay attention to that next time, but i think it does.
1f] Does your glow plug light come on? Y For how long? ~6 secs, then 5 times after that (GLE programming)
1g] Do you see smoke from the exhaust while cranking? What color? Not while cranking, but afterwards a little, as always before too
2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? Y, brandnew on 3-15
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? Could not check that yet. but assume OK, since LP new.
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] Heath PMD Isolator
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: ___________
3e] PMD Age: 5-3-08, 187k mls
4] no stalling issues
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? __________
6] Performance Issues
6a] Do you have gauges? Y
6b] Maximum boost under load? 12PSI
6c] Have you added a performance PCM (reflash) or Chip? Heath GLE
6d] Have you changed exhaust / downpipe / crossover? Heath Super Flow and Hi Flow Cross over, almost brandnew
6e] Wastegate – mechanical or vacuum? Heath TM for GM8
7] Temperature-related Issues:
7a] Single or dual thermostats? Dual
7b] Have you replaced them lately? Manufacturer of replacements? nope, have been there for a while
7c] Have you pulled and cleaned Radiator and coolers lately? nope
7d] Have you replaced the fan clutch? nope
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