Over the weekend I towed my lake bass boat and my envoy was a pig. my buddy met me at the lake and when done he towed the boat home with easr. he has a trail blazer and me an envoy both 4.2 3.73 gears and same size tires and he has 100k more miles then me. when I drove his I was impressed mine is a dog. he never changed out anything but cat back stock muffler as mine is stock and when driving I have to keep it in 3rd to keep rpm's up as we are in the mountains and his stays in D and flies. the chech engine light came on once cleares to never come back. is it time to pull the cat and get a better flow unit or go stock and put a magnaflow exhaust on it w/k&n intake filter and the ubit that controles torque changes in the tranny? I just find it weird I have way less miles and it is a real dog. I am close to putting my 87 burban back on the road doing minimal work to the voy and giving it to my kid but I dont want to hand him a lemon either. any ideas where to start. trust me the trailblazer feels like a sports car compared to my voy and i had plans for it. I like the little rig but my buddy towes a big camper with his and i can barely tow a light boat. Help....
same trucks 2 different power output.
- Thread starter minisuv
- Start date
Mounce
Member
Many different things it could be. What year is yours and what year is his? In 05 or 06 they changed the engines a little and they had more HP and torque.
Mooseman
Moderator
The stock exhausts already flow pretty good. Quite possibly the cat is partially plugged. You could go to a muffler shop and get a back pressure test done. Another way would be to remove the O2 sensor on the manifold and see if mileage improves.
If the cat needs to be replaced, a good aftermarket one will do. I don't know if a Magnaflow would really flow any better but at the RPM where you usually drive at, it probably wouldn't make much of a difference. Same for a performance exhaust and air filter. Just start with the basics. Also check your fan to be sure that it isn't locked up or working more than it should.
If you're getting intermittent CEL's, get a code reader and pull the code. It might be a clue to what's happening. If you don't have one, get a cheap one from Walmart or somewhere.
Is it possible that your buddy got a tune?
If the cat needs to be replaced, a good aftermarket one will do. I don't know if a Magnaflow would really flow any better but at the RPM where you usually drive at, it probably wouldn't make much of a difference. Same for a performance exhaust and air filter. Just start with the basics. Also check your fan to be sure that it isn't locked up or working more than it should.
If you're getting intermittent CEL's, get a code reader and pull the code. It might be a clue to what's happening. If you don't have one, get a cheap one from Walmart or somewhere.
Is it possible that your buddy got a tune?
Robbabob
Member
- Dec 10, 2012
- 1,096
DocBrown
Member
- Dec 8, 2011
- 501
X2 on all of the above. Not unusal for the CAT to clog between 80-120k miles. Often caused by running cold due to a faulty thoermostat. That causes the computer to run the engine rich which eventually toasts the CAT. If you don't tow something failry heavy regulaly you may not even reailize it's happening for a while. Really bad towing performance and mileage is why I discovered mine was clogged on my old TB.
C-ya
Member
- Aug 24, 2012
- 1,098
Granted, I have a 5.3, but the tune I got made a huge difference in how it tows. I had to tow my Squareback in 3rd because it hunted so much. I bought a Neon for my mom after the tune and towed it home (same trailer for both) and was able to keep it in D.
Of course, the maintenance items should be on the "to do" list, but if you do all that and his still pulls harder than yours, it could come down to the fact that his is tuned.
Of course, the maintenance items should be on the "to do" list, but if you do all that and his still pulls harder than yours, it could come down to the fact that his is tuned.
littleblazer
Member
- Jul 6, 2014
- 9,265
thanks im going to check the cat and resinator, as for the trucks we both have '04 4.2 same gears I have 80 k he has 178k and no tune he did say he had resinator delete. he sain a tune would do more damage in the long run but he has a set up to have the tranny locked up with torque and stronger shifting which he is putting in this weekend. it there a better cat or stock and i dont need to make it breath with an areochamber or magnaflo or flow master? does a resinater delete help? And do tuners destroy the truck in the long run. But stock like my buddys TB i would'nt need to as it hauls.
Gerbil21
Member
- May 28, 2014
- 839
How are you checking the temp? The gauge on the dash should be lined up with the 210minisuv said:
A tune if done correctly Such as one of the mail order tunes on this site should not damage anything unless you go crazy with transmission shifting. Also the setup he's putting in is it a shift kit? If so then that would help him out, especially with leaving it in drive since torque converter lockup is stronger. Also there's no need to go original with the cat it would cost alot more, just get either a bolt on cat or weld on cat from advance auto and use the code trt30 online to save some moneyminisuv said:
You shouldn't need anything extra if he's not using it either, just check the spark plugs, throttle body, cpas, air filter and check resonator
Also no, resonator delete dosent help with power unless it clogging which it can be if it's rusting it can collapse in itself
I looked underneith and seems I need exhaust. I am thinking a new muffler MAGANA FLOW a new resonator and which is the best cat? I donot want the popping sound. so i will keep the resonator. What is a good tune and tranny set up?
Gerbil21
Member
- May 28, 2014
- 839
Stock mufflers flow good so maybe try another one also if you don't want popping sound keep the resonator, the advanced auto cat is a magnaflow and I can say that it works good. For tune you can get a limeswap tune or pcm4less a lot of people say good things about the limeswap tune and its cheaper. Also for trans. Get the ctpowertrain kit on eBay its a great kit, and if you do get it make shure you get torlon check balls from them toominisuv said:
But make shure you check the things I posted before first especially the cpas (camshaft actuator) there is a article here on how to clean
Gerbil21
Member
- May 28, 2014
- 839
Cpas cleaning
http://gmtnation.com/forums/topic/2224-how-to-clean-the-camshaft-position-actuator-solenoid-cpas-picture-heavy/
Limswap tune
http://www.lime-swap.com/tune
Transmission kit
http://www.ebay.com/itm/4L60E-4L65E-1996-2006-1870-P1870-Code-Buster-Update-Kit-with-TransGo-SK4L60E-New-/350397097868
Checkballs
http://www.ebay.com/itm/700-4L60-700R4-4L60E-4L70-250-034-TORLON-CHECK-BALL-10-PC-/350353568123?&_trksid=p2056016.m2516.l5255
http://gmtnation.com/forums/topic/2224-how-to-clean-the-camshaft-position-actuator-solenoid-cpas-picture-heavy/
Limswap tune
http://www.lime-swap.com/tune
Transmission kit
http://www.ebay.com/itm/4L60E-4L65E-1996-2006-1870-P1870-Code-Buster-Update-Kit-with-TransGo-SK4L60E-New-/350397097868
Checkballs
http://www.ebay.com/itm/700-4L60-700R4-4L60E-4L70-250-034-TORLON-CHECK-BALL-10-PC-/350353568123?&_trksid=p2056016.m2516.l5255
Mooseman
Moderator
That transmission kit is wrong. It's for 1995 only.
I can vouch for Limeswap. Good service at less cost. Whoever said a tune will damage stuff is wrong as long as you get it from a reputable shop and don't go crazy with the specs. A regular mail order tune will be the same as what was successfully done to others.
If you like quiet, don't go with Magnaflow. Trust me.
(This one is mine)
https://www.youtube.com/watch?v=bn-_nTeBUaQ
https://www.youtube.com/watch?v=z3YuMRO5208
I have read that Walker mufflers neck down inside from 2.75 to 2.5" so if you're looking for flow, those aren't it. You'll have to do some research.
I can vouch for Limeswap. Good service at less cost. Whoever said a tune will damage stuff is wrong as long as you get it from a reputable shop and don't go crazy with the specs. A regular mail order tune will be the same as what was successfully done to others.
If you like quiet, don't go with Magnaflow. Trust me.
(This one is mine)
https://www.youtube.com/watch?v=bn-_nTeBUaQ
https://www.youtube.com/watch?v=z3YuMRO5208
I have read that Walker mufflers neck down inside from 2.75 to 2.5" so if you're looking for flow, those aren't it. You'll have to do some research.
Robbabob
Member
- Dec 10, 2012
- 1,096
minisuv said:
A proper T-stat will keep you just to the left of vertial, very close to the 210 mark. Running where you are may have already clogged up your Cat. Get the flow tested, or save the money for the test and just change it AND the T-stat. Any Cat should be okay (so I've read).Gerbil21 said:
Good luck!
Chickenhawk
Member
- Dec 6, 2011
- 782
Don't diagnose by throwing money at a problem. Set priorities. If you change ten things at a time, you will never know what worked and what is a waste of time and money.
Based on your posts, fix your coolant temp sensor and thermostat FIRST, then get your cat replaced.
You will then be able to stay neck and neck with your buddy.
THEN, worry about tunes, resonator deletes and all that other stuff.
A tune may marginally help but it is more for tip-in feel and firming up the shifts.
Resonator deletes will not affect acceleration or mileage.
Cold-air intakes are actually better termed warm-air intakes. They are ONLY for looks or sounds. They will marginally hurt acceleration because you are now sucking hot engine compartment air into your intake instead of cooler air from the air-to-air intercooler system on the stock air intake.
Based on your posts, fix your coolant temp sensor and thermostat FIRST, then get your cat replaced.
You will then be able to stay neck and neck with your buddy.
THEN, worry about tunes, resonator deletes and all that other stuff.
A tune may marginally help but it is more for tip-in feel and firming up the shifts.
Resonator deletes will not affect acceleration or mileage.
Cold-air intakes are actually better termed warm-air intakes. They are ONLY for looks or sounds. They will marginally hurt acceleration because you are now sucking hot engine compartment air into your intake instead of cooler air from the air-to-air intercooler system on the stock air intake.
I know these engines need good back pressure to run right so I dont want her to breath too much..Since the SS is hard to find I would love to put a 5.3 in and figure out a solid front axle set up.. Second part is a pipe dream but would be neat.Mooseman said:
HARDTRAILZ
Moderator
- Nov 18, 2011
- 49,665
BlazingTrails
Member
- Apr 27, 2014
- 19,409
My exhaust has zero back pressure. 0-60 in 7.6 seconds. You lose a little bottom end torque, but get a lot more mid to high range power.
Do they make a muffler where the resonator goes esp if you want to go duel exhaust look. or just run a muffler at it's point and use a decent resonator as i do not want to delete them.
HARDTRAILZ
Moderator
- Nov 18, 2011
- 49,665
Not sure why you want a resonator. It does very little but add weight and create something to drag or hang up on offroad.
You started this about more power and now you want to keep more exhaust restriction...makes no sense.
Also I reread the initial post....Dont waste money on K/N unless you want to add 100 times more dirt into your intake. Several of us use Green filters to keep high flow and decent filtering.
http://gmtnation.com/forums/topic/155-green-filter-experience/
You started this about more power and now you want to keep more exhaust restriction...makes no sense.
Also I reread the initial post....Dont waste money on K/N unless you want to add 100 times more dirt into your intake. Several of us use Green filters to keep high flow and decent filtering.
http://gmtnation.com/forums/topic/155-green-filter-experience/
HARDTRAILZ
Moderator
- Nov 18, 2011
- 49,665
I replied to your pM, but will toss a little of info here for posterity
Most of us hack off the resonator. Do it!
The stock intake flows pretty good so add a good filter and just cut it open if you desire.
PCM of NC has done me well over the course of a couple tunes and I still think it is one of the best bang per buck mods I have done out of the few mods i have.
Most of us hack off the resonator. Do it!
The stock intake flows pretty good so add a good filter and just cut it open if you desire.
PCM of NC has done me well over the course of a couple tunes and I still think it is one of the best bang per buck mods I have done out of the few mods i have.
has anyone gone with duel exhaust with 2 small mufflers in the rear and a mini where the stock is? just wondering
Mooseman
Moderator
I don't thing anybody here but Magnaflow has a cat-back kit but it includes a muffler and two resonators. There are some videos on YouTube on how it sounds. It will NOT sound like a V8. Performance wise, there is little to gain.