gtman
Senior Member
- First Name
- Mitch
- Joined
- Oct 27, 2015
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- 334
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- 16,997
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- Location
- USA
- Website
- www.civicx.com
- Vehicle(s)
- 2017 Cosmic Blue EX-L Sedan
- Vehicle Showcase
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- #1
reliability [ri-lahy-uh-bil-i-tee]: the ability to be relied on or depended on
Everyone knows that tuning improves performance. But what about long term reliability and safety?
I created this thread to try to document just that and to get an overview of owner's overall tuning experiences.
If you have a tuned 10th gen, help the community and add your car to the thread. Your tuning experience and reliability data is invaluable (includes Type R, Si, 1.5T and 2.0 NA).
Every tuned car added helps build our tuning knowledge base and helps others decide if tuning is right for them.
Please use the format below when adding your car to the thread (my car used as an example):
Vehicle: 2017 Civic EX-L sedan
Total tuned time: 6 years, 1 month
Tuned miles driven: 34,000
Tuning device(s) used: I started with a Hondata CARB Flashpro and currently use a KTuner V2
Tunes used: Hondata +6 and my own +7.5 tune; KTuner Dual Starter 21; D-Rob customized TSP 1; Phearable 1.5; currently using Phearable's 1.5R tune
Fuel used: Sunoco 93 Ultra (exclusively)
Additional related mods: PRL silicone intake hose, aFe Pro Dry S filter, Ruthenium HX plugs
Problems/issues: None
Driving style: Slightly speedy with aggressive bursts from time to time, mostly on the highway. With the better response and power, merging and avoiding dicey situations in traffic is much improved.
Tune experience notes: Overall the factory tune is mediocre at best. There was some serious lag going from light to heavy throttle. Tuning has definitely reduced the lag by maybe 90% and gives me a completely different (and safer) driving experience. I've never had a mod transform a car like tuning has. My car went from a peppy commuter to a bit of a sleeper and mpgs are only a bit lower since tuning (mostly due to a heavier foot). The Phearable 1.5R is the best tune I've used so far. It's super smooth, yet potent.
At the end of your post feel free to add photos, videos, dragy results, timeslips and dyno sheets.
Adding update posts: Add a new post from time to time. Use that post to show additional tuned miles driven, changes to your tune or mod setup, any issues that occur and any new tuning experience notes. Update posts help increase the thread's accuracy. Update with a new post only. Never edit and overwrite your original post.
Thread stats, notes and information (4/24/24)
General stats
Total tuned cars submitted: 1,309
Non-Si 577; Si 561; Type R 123; 2.0 NA 48
Sedan 633; Hatchback 443; Coupe 233
Manual trans 862 (66%); CVT 447 (34%)
Total reported tuned miles: 25,000,900
Car with most tuned miles: 160,000
Major failure stats
Cars with major drivetrain failures: 54 (4.1%)
Failures by model: Si 22; Non-Si 28; 2.0 NA 2; CTR 2
Highest fail rate: 1.5T hatchbacks (6.0%)
Failures by tune type: Base 15; OTS 18; Custom 21*
Failure rate: OTS 2.9%; Base 3.9%; Custom: 7.5%
Engine failures: Si 15; Non-Si 21; 2.0 NA 1; CTR 2
Transmission failures: CVT 8; Manual 7
Device usage stats
Hondata used for tuning: 292; Race (257) Carb (35)
KTuner used for tuning: 1,065; V1.2 (576) V2 (489)
Other devices: JB4 4; RaceChip 6; Motec 4; Cobb 1
Usage rate: KTuner 77%; Hondata 22%; Other 1%
Tune type stats
Currently custom tuned cars: 281 (22%)
Currently OTS tuned cars: 638 (49%)
Currently base tuned cars: 390 (29%)
Tune usage stats
Most popular OTS tune: TSP Stage 1 (455)
Other popular OTS tunes: Phearable 1.5 (259);
Phearable 1.5R (138); TSP Stage 1+ (82);
TSP Stage 2 (40); Phearable 2.5 (35)
Phearable OTS revision tunes: 27
Cars on custom flex fuel tunes: 76
Fuel usage stats
Users running 93 octane: 679 (52%)
Users running 91 octane: 464 (35%)
Other octanes used: 166 (13%)
Octane booster used: 25 (2%)
Users topping off with E85: 147 (11%)
Flex fuel kits installed: 176 (13%)
Bolt on stats
No bolt ons added: 321 (25%)
Bolt ons added (not FBO): 718 (54%)
Cars with full bolt ons: 270 (21%)
Related mod stats
Cold air intake installed: 653 (50%)
Short ram intake installed: 147 (11%)
Upgraded intercooler installed: 498 (39%)
Upgraded charge pipes: 197 (16%)
Aftermarket downpipe installed: 475 (36%)
Aftermarket frontpipe installed: 335 (25%)
Aftermarket exhaust installed: 433 (32%)
Upgraded RMM installed: 169 (12%)
Upgraded flywheel installed: 106 (12%)
Upgraded clutch installed: 201 (23%)
Upgraded CMC installed: 40 (4%)
Catch can installed: 93 (7%)
Oil or trans cooler installed: 46 (4%)
Upgraded fuel pump installed: 40 (3%)
Upgraded fuel system installed: 24 (2%)
Upgraded radiator installed: 29 (2%)
Upgraded head studs installed: 56 (4%)
Aftermarket intake manifold: 15 (1%)
Aftermarket BOV installed: 38 (3%)
Upgraded turbo inlet pipe: 185 (14%)
Turbo blanket installed: 38 (3%)
4 bar MAP sensor installed: 16 (1%)
Upgraded turbo installed: 151 (12%)
Cars with built engines: 22
Tuned miles stats
Under 10,000 tuned miles driven: 463
10,000-25,000 tuned miles driven: 509
25,001-40,000 tuned miles driven: 187
40,001-60,000 tuned miles driven: 86
60,001-75,000 tuned miles driven: 35
75,001-100,000 tuned miles driven: 18
Over 100,000 tuned miles driven: 11
Stats notes
For this thread, full bolt ons consist of downpipe, frontpipe, intercooler and intake at a minimum. The most popular installed bolt ons are intakes (61%), intercoolers, downpipes and exhaust systems. PRL Cobras are the most popular intake with 366 installs (298 CAI, 68 SRI). Only 39% of all owners with upgraded intercoolers have upgraded the charge pipes.
Nearly 46% of KTuner owners use the touchscreen V2 version. 89% of Hondata owners use the Race version. While KTuner is used by the majority of owners in the thread, Type R owners prefer Hondata.
45% of the cars in the thread are 1.5T Non-Si's. 42% are Si's. 10% are Type R's. 3% are 2.0 NA's. 48% of the cars in the thread are sedans. 34% are hatchbacks. 18% are coupes. 336 owners in the thread have driven at least 25,000 tuned miles. 150 owners have over 40,000 tuned miles driven. 64 owners have driven more than 60,000 tuned miles.
The tuned miles driven stats are based on the info currently reported by owners. The tune type stats are based on the owner's current reported tune. The drivetrain failures link takes you to a separate thread with additional details and information.
Major Failures
1 car had a failed CVT (replaced under warranty). 1 car had a blown head gasket. 1 car blew a CVT pushing the car hard with an existing emissions problem. 1 car blew an engine running an E35/meth setup. 1 car blew an engine when the owner mistakenly used non-race gas with a tune designed specifically for race gas. 1 owner had major failures on a used car he purchased. 1 owner admitted he abused his car and destroyed his engine. 1 non-Si owner blew his engine on a Stage 2 Powermetric flex fuel tune w/full bolt ons. 1 owner had his CVT replaced under warranty (damaged by high power ethanol tune); the new CVT has been trouble free for 70,000+ tuned miles. 1 car threw a rod under "iffy" circumstances according to it's owner (possible abuse/user error). 1 owner destroyed his CVT after some track time in 100° weather.
1 car had a bent connecting rod but there were many factors (neglect) beyond the tune. 1 Si blew two OEM head gaskets (finally replaced with a better aftermarket gasket). 1 car bent a rod while doing WOT datalogging for a custom remote tune (had run meth for a short time as well). 1 car blew a CVT after serious neglect/abuse with numerous brake launches and burnouts. 1 Si blew a transmission running a high power flex fuel tune (full bolt ons). 1 car bent rods, had bearing material in the oil and CVT issues. 1 Si blew the head gasket and lifted the head after 14,000 aggressively driven tuned miles. 1 Type R had overheating issues; blew the head gasket and the top piston ring scored the cylinder wall; engine replaced. 1 car had a failed CVT running a base tune on a stock setup (likely factory defective; replaced under warranty). 1 car bent a rod after filling up with low octane gas (sold as high octane) in Egypt.
1 car bent a rod on a high output custom tune during a WOT pull. 1 car had a catastrophic engine failure when a tuner bumped up low end torque too far. 1 car (a 1.5T hatch) had an engine failure where octane booster possibly contributed. 1 hatch blew an engine after adding too much octane booster to the tank. 1 Si blew a head gasket running a high power flex fuel tune. 1 custom tuned 2.0NA had a CVT failure. 1 Si failed when the engine seized up due to a likely oil pump failure. 1 Non-Si engine was destroyed when the intake camshaft snapped possibly due to a defective oil pump. 1 hatchback bent a rod running a base tune with no bolt ons. 1 Si needed a transmission replacement due to a bearing failure (replaced under warranty). 1 Si had damaged engine bearings likely due to a failed oil pump. 1 car's engine had a spun rod bearing.
1 Si owner blew his transmission after admittedly beating on his car long term. 1 Si blew a head gasket on an OTS flex fuel tune. 1 Si blew it's transmission after many hard driven miles on a high power tune. 1 Non-Si owner had a failed CVT on a car he purchased used. 1 hatchback owner blew his engine on a +6 Hondata base tune. 1 CTR track car suffered a blown head gasket and scored cylinder walls. 1 OTS tuned Si had a head gasket failure. 1 aggressively driven Si (on an OTS ethanol tune) had a transmission failure. 1 W2 powered Si had a failed head gasket. 1 Non-Si in Australia blew a rod when the owner neglected a long term engine knocking issue. 1 Non-Si on a high power custom flex tune had a head gasket failure. 1 Si on a TSP1 had head gasket and rod bearing failures. 1 hatchback blew a rod and shattered a piston.
1 Si had a transmission failure (lost 4th gear) caused by user error. 1 aggressively driven flex fuel tuned Si blew a transmission. 1 high mileage used Si had scored cylinder walls and head gasket issues. 1 owner-tuned hatchback (30 psi) not surprisingly blew a rod. 1 Si had a blown CV axle, spun rod bearing, spun thrust bearing and a scored oil pump housing. 1 Si running the TSP 1+ tune threw a rod. 1 hatchback had a rod through the block. 1 aggressively driven 2.0 NA blew a head gasket, spun the main bearings and had other issues.
Failure Notes
1.5T Non-Si's in the thread have had the most major failures (21 engine; 7 CVT) and have the highest overall failure rate (4.9%). It's important to note that 14 of the 17 Non-Si rod failures (82%) occurred in hatchback models. The hatchback's weaker rods clearly skew the overall Non-Si failure rate stats. The sedan/coupe major failure rate is 3.5% (9 failures).
Si's in the thread have had 22 major failures (15 engine; 7 transmission) for a 4.0% failure rate. Head gaskets (9) account for 60% of the Si engine problems. By comparison, only 2 of the 20 Non-Si engine failures were head gaskets (10%) The issue seems to mostly affect higher output Si's that have been tuned for an extended time.
Type R's currently have a 1.8% failure rate with 2 cars having engine failures (both were track cars). 2.0 NA's have a 4.2% failure rate with two major failures (1 CVT, 1 engine). 4 of the 54 major failures were on cars running no bolt-on setups (7%).
While no engine failures were covered under warranty some of the transmission failures were. 5 of the 8 CVTs that failed were replaced under warranty (62%). Only 1 of the 5 failed manual transmissions was replaced under warranty (20%).
* The failures by tune type stats are based on the tune the owner was running at the time of the failure.
Lesser Failures and Issues
Many manual owners in the thread have reported clutch slip issues. Some CVT owners have reported occasional whining or other wonkiness. There's been occasional fuel trim and knock control issues (depending on intake and gas used). 35 owners in the thread (3%) have reported injector failures. Five W1 aftermarket turbos have failed. All of these are concerning but not catastrophic.
Observations
An OTS tune, running 93 octane with no added bolt ons appears to be the most reliable setup. Unlike base tunes, OTS tunes are mostly locked and allow few user adjustments, increasing safety. Issues seem to happen most often when power output is pushed too high, owners attempt to self-tune or there is abuse, neglect or user error involved. Due to potential long term issues, octane boosters, aftermarket blow-off valves and Injen intakes aren't recommended.
CVTs and Tuning
Some people say it's a waste to tune a 1.5T CVT Civic. The idea being that the CVT can't handle high power and that they're boring. This video of a John Vega tuned sedan might change that point of view. The fact is, a higher power tuned CVT turbo Civic can be both reliable (limiting torque down low is a key) and fun. In the thread, 71% of the Non-Si 1.5Ts are CVT.
Top rated tuners: Derek Robinson; John Vega
Searching the thread
Use this post to search for specific information in the thread quickly. It features links to many useful tuning related search terms. It's an easy way to find the information you want.
Summary
There's no doubt that a tune is the single best power-based performance mod but it does add additional stress. Reliability can be compromised if you tune for ultimate power (on stock internals) or abuse or neglect your ride. And while the jury is still out on long term 10th gen tuning reliability, proper maintenance and common sense on the road will help minimize issues. - gtman
Everyone knows that tuning improves performance. But what about long term reliability and safety?
I created this thread to try to document just that and to get an overview of owner's overall tuning experiences.
If you have a tuned 10th gen, help the community and add your car to the thread. Your tuning experience and reliability data is invaluable (includes Type R, Si, 1.5T and 2.0 NA).
Every tuned car added helps build our tuning knowledge base and helps others decide if tuning is right for them.
Please use the format below when adding your car to the thread (my car used as an example):
Vehicle: 2017 Civic EX-L sedan
Total tuned time: 6 years, 1 month
Tuned miles driven: 34,000
Tuning device(s) used: I started with a Hondata CARB Flashpro and currently use a KTuner V2
Tunes used: Hondata +6 and my own +7.5 tune; KTuner Dual Starter 21; D-Rob customized TSP 1; Phearable 1.5; currently using Phearable's 1.5R tune
Fuel used: Sunoco 93 Ultra (exclusively)
Additional related mods: PRL silicone intake hose, aFe Pro Dry S filter, Ruthenium HX plugs
Problems/issues: None
Driving style: Slightly speedy with aggressive bursts from time to time, mostly on the highway. With the better response and power, merging and avoiding dicey situations in traffic is much improved.
Tune experience notes: Overall the factory tune is mediocre at best. There was some serious lag going from light to heavy throttle. Tuning has definitely reduced the lag by maybe 90% and gives me a completely different (and safer) driving experience. I've never had a mod transform a car like tuning has. My car went from a peppy commuter to a bit of a sleeper and mpgs are only a bit lower since tuning (mostly due to a heavier foot). The Phearable 1.5R is the best tune I've used so far. It's super smooth, yet potent.
At the end of your post feel free to add photos, videos, dragy results, timeslips and dyno sheets.
Adding update posts: Add a new post from time to time. Use that post to show additional tuned miles driven, changes to your tune or mod setup, any issues that occur and any new tuning experience notes. Update posts help increase the thread's accuracy. Update with a new post only. Never edit and overwrite your original post.
Thread stats, notes and information (4/24/24)
General stats
Total tuned cars submitted: 1,309
Non-Si 577; Si 561; Type R 123; 2.0 NA 48
Sedan 633; Hatchback 443; Coupe 233
Manual trans 862 (66%); CVT 447 (34%)
Total reported tuned miles: 25,000,900
Car with most tuned miles: 160,000
Major failure stats
Cars with major drivetrain failures: 54 (4.1%)
Failures by model: Si 22; Non-Si 28; 2.0 NA 2; CTR 2
Highest fail rate: 1.5T hatchbacks (6.0%)
Failures by tune type: Base 15; OTS 18; Custom 21*
Failure rate: OTS 2.9%; Base 3.9%; Custom: 7.5%
Engine failures: Si 15; Non-Si 21; 2.0 NA 1; CTR 2
Transmission failures: CVT 8; Manual 7
Device usage stats
Hondata used for tuning: 292; Race (257) Carb (35)
KTuner used for tuning: 1,065; V1.2 (576) V2 (489)
Other devices: JB4 4; RaceChip 6; Motec 4; Cobb 1
Usage rate: KTuner 77%; Hondata 22%; Other 1%
Tune type stats
Currently custom tuned cars: 281 (22%)
Currently OTS tuned cars: 638 (49%)
Currently base tuned cars: 390 (29%)
Tune usage stats
Most popular OTS tune: TSP Stage 1 (455)
Other popular OTS tunes: Phearable 1.5 (259);
Phearable 1.5R (138); TSP Stage 1+ (82);
TSP Stage 2 (40); Phearable 2.5 (35)
Phearable OTS revision tunes: 27
Cars on custom flex fuel tunes: 76
Fuel usage stats
Users running 93 octane: 679 (52%)
Users running 91 octane: 464 (35%)
Other octanes used: 166 (13%)
Octane booster used: 25 (2%)
Users topping off with E85: 147 (11%)
Flex fuel kits installed: 176 (13%)
Bolt on stats
No bolt ons added: 321 (25%)
Bolt ons added (not FBO): 718 (54%)
Cars with full bolt ons: 270 (21%)
Related mod stats
Cold air intake installed: 653 (50%)
Short ram intake installed: 147 (11%)
Upgraded intercooler installed: 498 (39%)
Upgraded charge pipes: 197 (16%)
Aftermarket downpipe installed: 475 (36%)
Aftermarket frontpipe installed: 335 (25%)
Aftermarket exhaust installed: 433 (32%)
Upgraded RMM installed: 169 (12%)
Upgraded flywheel installed: 106 (12%)
Upgraded clutch installed: 201 (23%)
Upgraded CMC installed: 40 (4%)
Catch can installed: 93 (7%)
Oil or trans cooler installed: 46 (4%)
Upgraded fuel pump installed: 40 (3%)
Upgraded fuel system installed: 24 (2%)
Upgraded radiator installed: 29 (2%)
Upgraded head studs installed: 56 (4%)
Aftermarket intake manifold: 15 (1%)
Aftermarket BOV installed: 38 (3%)
Upgraded turbo inlet pipe: 185 (14%)
Turbo blanket installed: 38 (3%)
4 bar MAP sensor installed: 16 (1%)
Upgraded turbo installed: 151 (12%)
Cars with built engines: 22
Tuned miles stats
Under 10,000 tuned miles driven: 463
10,000-25,000 tuned miles driven: 509
25,001-40,000 tuned miles driven: 187
40,001-60,000 tuned miles driven: 86
60,001-75,000 tuned miles driven: 35
75,001-100,000 tuned miles driven: 18
Over 100,000 tuned miles driven: 11
Stats notes
For this thread, full bolt ons consist of downpipe, frontpipe, intercooler and intake at a minimum. The most popular installed bolt ons are intakes (61%), intercoolers, downpipes and exhaust systems. PRL Cobras are the most popular intake with 366 installs (298 CAI, 68 SRI). Only 39% of all owners with upgraded intercoolers have upgraded the charge pipes.
Nearly 46% of KTuner owners use the touchscreen V2 version. 89% of Hondata owners use the Race version. While KTuner is used by the majority of owners in the thread, Type R owners prefer Hondata.
45% of the cars in the thread are 1.5T Non-Si's. 42% are Si's. 10% are Type R's. 3% are 2.0 NA's. 48% of the cars in the thread are sedans. 34% are hatchbacks. 18% are coupes. 336 owners in the thread have driven at least 25,000 tuned miles. 150 owners have over 40,000 tuned miles driven. 64 owners have driven more than 60,000 tuned miles.
The tuned miles driven stats are based on the info currently reported by owners. The tune type stats are based on the owner's current reported tune. The drivetrain failures link takes you to a separate thread with additional details and information.
Major Failures
1 car had a failed CVT (replaced under warranty). 1 car had a blown head gasket. 1 car blew a CVT pushing the car hard with an existing emissions problem. 1 car blew an engine running an E35/meth setup. 1 car blew an engine when the owner mistakenly used non-race gas with a tune designed specifically for race gas. 1 owner had major failures on a used car he purchased. 1 owner admitted he abused his car and destroyed his engine. 1 non-Si owner blew his engine on a Stage 2 Powermetric flex fuel tune w/full bolt ons. 1 owner had his CVT replaced under warranty (damaged by high power ethanol tune); the new CVT has been trouble free for 70,000+ tuned miles. 1 car threw a rod under "iffy" circumstances according to it's owner (possible abuse/user error). 1 owner destroyed his CVT after some track time in 100° weather.
1 car had a bent connecting rod but there were many factors (neglect) beyond the tune. 1 Si blew two OEM head gaskets (finally replaced with a better aftermarket gasket). 1 car bent a rod while doing WOT datalogging for a custom remote tune (had run meth for a short time as well). 1 car blew a CVT after serious neglect/abuse with numerous brake launches and burnouts. 1 Si blew a transmission running a high power flex fuel tune (full bolt ons). 1 car bent rods, had bearing material in the oil and CVT issues. 1 Si blew the head gasket and lifted the head after 14,000 aggressively driven tuned miles. 1 Type R had overheating issues; blew the head gasket and the top piston ring scored the cylinder wall; engine replaced. 1 car had a failed CVT running a base tune on a stock setup (likely factory defective; replaced under warranty). 1 car bent a rod after filling up with low octane gas (sold as high octane) in Egypt.
1 car bent a rod on a high output custom tune during a WOT pull. 1 car had a catastrophic engine failure when a tuner bumped up low end torque too far. 1 car (a 1.5T hatch) had an engine failure where octane booster possibly contributed. 1 hatch blew an engine after adding too much octane booster to the tank. 1 Si blew a head gasket running a high power flex fuel tune. 1 custom tuned 2.0NA had a CVT failure. 1 Si failed when the engine seized up due to a likely oil pump failure. 1 Non-Si engine was destroyed when the intake camshaft snapped possibly due to a defective oil pump. 1 hatchback bent a rod running a base tune with no bolt ons. 1 Si needed a transmission replacement due to a bearing failure (replaced under warranty). 1 Si had damaged engine bearings likely due to a failed oil pump. 1 car's engine had a spun rod bearing.
1 Si owner blew his transmission after admittedly beating on his car long term. 1 Si blew a head gasket on an OTS flex fuel tune. 1 Si blew it's transmission after many hard driven miles on a high power tune. 1 Non-Si owner had a failed CVT on a car he purchased used. 1 hatchback owner blew his engine on a +6 Hondata base tune. 1 CTR track car suffered a blown head gasket and scored cylinder walls. 1 OTS tuned Si had a head gasket failure. 1 aggressively driven Si (on an OTS ethanol tune) had a transmission failure. 1 W2 powered Si had a failed head gasket. 1 Non-Si in Australia blew a rod when the owner neglected a long term engine knocking issue. 1 Non-Si on a high power custom flex tune had a head gasket failure. 1 Si on a TSP1 had head gasket and rod bearing failures. 1 hatchback blew a rod and shattered a piston.
1 Si had a transmission failure (lost 4th gear) caused by user error. 1 aggressively driven flex fuel tuned Si blew a transmission. 1 high mileage used Si had scored cylinder walls and head gasket issues. 1 owner-tuned hatchback (30 psi) not surprisingly blew a rod. 1 Si had a blown CV axle, spun rod bearing, spun thrust bearing and a scored oil pump housing. 1 Si running the TSP 1+ tune threw a rod. 1 hatchback had a rod through the block. 1 aggressively driven 2.0 NA blew a head gasket, spun the main bearings and had other issues.
Failure Notes
1.5T Non-Si's in the thread have had the most major failures (21 engine; 7 CVT) and have the highest overall failure rate (4.9%). It's important to note that 14 of the 17 Non-Si rod failures (82%) occurred in hatchback models. The hatchback's weaker rods clearly skew the overall Non-Si failure rate stats. The sedan/coupe major failure rate is 3.5% (9 failures).
Si's in the thread have had 22 major failures (15 engine; 7 transmission) for a 4.0% failure rate. Head gaskets (9) account for 60% of the Si engine problems. By comparison, only 2 of the 20 Non-Si engine failures were head gaskets (10%) The issue seems to mostly affect higher output Si's that have been tuned for an extended time.
Type R's currently have a 1.8% failure rate with 2 cars having engine failures (both were track cars). 2.0 NA's have a 4.2% failure rate with two major failures (1 CVT, 1 engine). 4 of the 54 major failures were on cars running no bolt-on setups (7%).
While no engine failures were covered under warranty some of the transmission failures were. 5 of the 8 CVTs that failed were replaced under warranty (62%). Only 1 of the 5 failed manual transmissions was replaced under warranty (20%).
* The failures by tune type stats are based on the tune the owner was running at the time of the failure.
Lesser Failures and Issues
Many manual owners in the thread have reported clutch slip issues. Some CVT owners have reported occasional whining or other wonkiness. There's been occasional fuel trim and knock control issues (depending on intake and gas used). 35 owners in the thread (3%) have reported injector failures. Five W1 aftermarket turbos have failed. All of these are concerning but not catastrophic.
Observations
An OTS tune, running 93 octane with no added bolt ons appears to be the most reliable setup. Unlike base tunes, OTS tunes are mostly locked and allow few user adjustments, increasing safety. Issues seem to happen most often when power output is pushed too high, owners attempt to self-tune or there is abuse, neglect or user error involved. Due to potential long term issues, octane boosters, aftermarket blow-off valves and Injen intakes aren't recommended.
CVTs and Tuning
Some people say it's a waste to tune a 1.5T CVT Civic. The idea being that the CVT can't handle high power and that they're boring. This video of a John Vega tuned sedan might change that point of view. The fact is, a higher power tuned CVT turbo Civic can be both reliable (limiting torque down low is a key) and fun. In the thread, 71% of the Non-Si 1.5Ts are CVT.
Top rated tuners: Derek Robinson; John Vega
Searching the thread
Use this post to search for specific information in the thread quickly. It features links to many useful tuning related search terms. It's an easy way to find the information you want.
Summary
There's no doubt that a tune is the single best power-based performance mod but it does add additional stress. Reliability can be compromised if you tune for ultimate power (on stock internals) or abuse or neglect your ride. And while the jury is still out on long term 10th gen tuning reliability, proper maintenance and common sense on the road will help minimize issues. - gtman
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