looking to get more out of my engine without breaking it.
i’ve seen it perform better than how it came but now it’s learned. i need to get that extra hp and economy back, plus more.
wondering if mechanics will do this, and if bullydogs can be borrowed for one use.
I don’t know of a mechanic that would do this.
It could be considered as emissions tampering.
Tester
Leave it stock. Its unlikely a random mechanic is going to improve upon the work of the engineers that designed it. Reminds me of when we used to “DynoTune” cars by re-curving the distributors and re-jetting the carburetors.
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If you had it before and now lost it. i suggest you get a tune-up
What year and engine are you talking about for your 1500??
Is it all stock, exhaust, intake, throttle body, injectors, cam, valve springs???
What do you mean?? Have you already had a tune put in it?? how did it learn and now you have lost HP and mileage??
Depending on vehicle and engine combo the OEM engineers have a pretty good tune in it to begin with… unless you have modified it performance wise not worth the $$$
But you need to contact a tuner that can use a chassis dyno and road tune it or you are not going to get the best tune out of it…
EDIT: A friend of mine had a 2014 Challenger R/T 5.7 that was 375 HP before we installed headers, deleted the cats and basically straight piped it, cold air induction and I think a bigger throttle body and it cost him $600 every time he changed something, and only got about 425 hp out of it… After we did the cat deleted I changed the rear gear in my old junk and could beat him, when I said I had ordered a new cam and some other goodies he traded it in for a 2021 Scat Pack 6.4L 485 HP Wide Body Challenger hoping to beat me once I upgrade, he has it up to 525HP now lol…
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You either need to buy your own tuning device or find a performance shop to do the tune for you. The device will run you $500 or so, the shop more.
Don’t expect a lot of hp gain especially if you want to still run 89 octane fuel. The biggest gains are with 91 octane.
And the EPA is cracking down on these devices and tuners so some are.getting out of that business.
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First of all, if your truck is equipped with a NA gasoline engine, “tuning” the PCM is unlikely to improve performance at all. The good news is than with no forced induction, you don’t have to worry about breaking anything mechanically in the engine.
Second, an engine delivers its maximum HP at high RPMs, and that is generally only useful for bragging rights, especially if paired with an automatic transmission. What makes a car feel fast is torque, not HP, and even cars with comparatively low HP can feel fast if the engine is tuned for maximum torque delivery at lower speeds.
A good example is the Chrysler 2.2 and 2.5 4-cylinder engines used in the mid-1980s to mid-1990s. These engines offered little in the way of horsepower, but provided tremendous torque, especially at low RPMs, which is what gets you moving from a standstill. The quick acceleration makes the car feel fast, even with less than 120 HP.
Third, if you feel that the performance of your truck has deteriorated, it would make more sense to check for possible mechanical problems/worn parts than to consider “tuning” the PCM.
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Bullydog has a dealer locator on their site, might be a shop willing to install a tune for a fee, Closest dealer’s to me run the gamut from performance shops to small town Chevy dealer’s.
i pulled the ABS fuse out, truck had amazing performance until it re-learned while being driven.
governor puts the rpm way higher than it needs to be while telling pcm to output slower for safety.
difference being 0-25mph @ 500-1500rpm without fuse vs 0-25 @ 500-2500rpm with it.
truck makes more noise and gets less performance by a long shot with its factory tune.
looking to bring it back to how it was when i first pulled the fuse and also keep my ABS and TC
I’m struggling to understand how pulling the ABS (braking?) fuse brought about “amazing performance.”
Leave the engine alone, kid. You’re playing with fire. And if it’s a new truck with factory warranty, it’s more like Russian roulette.
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nobody likes to be talked to like that. save it for your mama.
no surprise there
I will ask my very 1st question again…
- Why was the ABS fuse pulled in the 1st place??
- So, did the truck gain power when you removed the ABS fuse??
- Or did it change any after pulling the fuse and lost power once the PCM “relearned” having the fuse pulled out???
Just trying to wrap my head around the abs fuse missing giving you HP…
You may get more questions then answers at 1st, but just try to answer all of them as it will help…
If you put the fuse back and your rpms jump from 1500 rpm to 2500 rpm at 25 mph then it sounds like the abs module is keeping the brakes applied or more so restricting the bleed off…
The ABS does not change the stall speed nor the rear gear ratio, but the brakes dragging will hold the vehicle back loading the torque converter making it stall at a higher (or max stall) speed (kinda like foot braking it to get a higher rpm launch) … As the rpms come up the engine should make more power when down low like that and it sounds like yours is doing the opposite which makes me even more believe you have a brake dragging issue…
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I’m also not “surprised” that you can’t explain to me how changing the vital braking function of your vehicle somehow “increases” engine performance.
You posted this question of a forum of knowledgeable, caring people who know the dangers of messing with car/engine stuff not complete understood. If you choose to ignore the advice you’re given, that’s up to you. The “friends” you’re likely trying to impress won’t help you much when you have a blown engine or wrecked vehicle.
I wish you luck.
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howdy
its a 4.8 v8.
it was pulled because I wanted to do burnouts
don’t have the equipment to be certain of any power gain, but it did gain throttle responsiveness and fuel economy.
lost the responsiveness when the pcm relearned. took a couple days.
i’m willing to buy into this diagnosis
the brakes are wobbly when stepped on and have warped twice within 10k miles. i think it’s warped.
they shake hard when brake applied…
jiggles the truck fast.
wear indicators squeak more when turning right
one tech said maybe the engine mounts were bad causing brake wear.
but a bleeder issue causing brake drag could probably cause the rotors warping too right?
furthering discussion:
different issue.
the truck would not start right up from the first few turns of the key( with the abs fuse in). I had the sensor behind the engine replaced. no fix.
It cranks, sparks, fuels, but no start. pulled fuse out, and magic. its starting after less failed attempts. significantly less. from 4+ to <2 tries.
so weve got possible bleeder issue from abs causing warping and drag, leading to higher rpm, louder, slower, and less efficient performance. And the ABS or another module on the same fuse, responsible for unreliable start up of the motor?
one last sprinkle of joy:
i had to replace the ignition key. this tidbit didn’t come to me until much later. when I installed the new key hole next to the steering wheel, I had some trouble positioning the gearing, prior to closing everything up. this led me to trying it several times by taking it all apart and adjusting it slightly until it worked. At first, I could not turn the key far enough to engage the crank. so I adjusted it carefully until it worked. now I’m thinking this problem with the starting of the motor could be due to needing to adjust that key mechanism just a little farther.
thanks
when I pulled the ABS fuse, you said leave the engine alone. genius.
That was a really well-informed and helpful answer. Thanks very much.
What Year is the truck???
Did the CEL come on after the fuse was pulled and it lost performance???
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So we still don’t know the year…
That “power” you think you got doing burnouts was because the ABS, stability control and traction control were disabled so you could hoon. If your “butt dyno” reads less power it is because the traction control is lowering the power to prevent you spinning your tires. With better tires, this would not happen.
A tune will do nothing for this. Tunes change the engine control computer calibrations but do nothing to change the ABS computer calibrations which feed information to the engine computer for traction control.
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