Hesitates after H/C
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From: Land of the FOID
Hesitates after H/C So after my H/C install I have it dyno tuned and everything seems fine. But now I notice when I start the car after the first 30sec or so the car sputters and hesitates like it has no power...almost like a plug wire is bad. Then all is well and the car drives just great. I did put new plugs and wires on it during install.
I called the tuner and asked him and he said that was normal for a H/C car. It may be but I just wanted to get other opinions and check anything if needed. I've driven in other cammed cars and didn't feel this at all.
Thanks!
I called the tuner and asked him and he said that was normal for a H/C car. It may be but I just wanted to get other opinions and check anything if needed. I've driven in other cammed cars and didn't feel this at all.
Thanks!
Mine does it too when I first crank up and leave in the morning. But after like 1/2 a mile to the stop light it's fine and it's even worse in the winter, but I'd say it's probably normal because I replaced plugs and wires at the time of my H/C install
It is not normal.
I've said this a number of times but I'm going to repeat myself. A dyno tune isn't about driveability. It's about wide open throttle tuning and it is generally used as a tool to separate customers from large sums of money to provide a simple dyno sheet.
Driveability issues are solved by doing cold starts and setting those parameters and doing stop & go driving and logging the data to make adjustments.
A full proper tune takes time - lots of time.
I've said this a number of times but I'm going to repeat myself. A dyno tune isn't about driveability. It's about wide open throttle tuning and it is generally used as a tool to separate customers from large sums of money to provide a simple dyno sheet.
Driveability issues are solved by doing cold starts and setting those parameters and doing stop & go driving and logging the data to make adjustments.
A full proper tune takes time - lots of time.
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From: Auckland, Nth Is, New Zealand.
A dyno is a tuning tool, if someone had a car they raced on race fuel and also used it say as a weekend driver, they may have a twin tune set up in the computer so they could switch to pump fuel.
You don't have a street tune & a dyno tune.
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Verdad Gallardo In most instances the dyno is not used as a tuning tool, it is simply used to show a "before" snapshot and an "after" snapshot to impress the customer. That being said, there are a handful of guys around that will data log on the street under normal starting and driving conditions and make necessary adjustments to spark advance, VE, Maf freq, Throttle cracker/follower, etc., for optimum street driving and also put the car on a dyno to get WOT fueling and spark advance where it needs to be.
One or two WOT pulls are what a whole host of people mistakenly refer to as a dyno tune because it has been marketed as such by a bunch of posers.
One or two WOT pulls are what a whole host of people mistakenly refer to as a dyno tune because it has been marketed as such by a bunch of posers.
Sounds like it's tune related. It depends on what temp is set in the PCM, but that is probably when the car goes into closed loop. So runs bad in open loop, then when it goes closed loop it runs ok.
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From: Land of the FOID
Alright....thanks. It's gotta go in for cold start issues so maybe that will take care of the hesitation. I'm gonna press them on it again when I bring it back next week. For that kind of money it should run a little smoother.
Do you even know what the hell your talking about? I can't even comprehend what on earths going through your mind about tuning a car, i sincerely suggest you do a search on tuning and or speak to others that have some idea.
A dyno is a tuning tool, if someone had a car they raced on race fuel and also used it say as a weekend driver, they may have a twin tune set up in the computer so they could switch to pump fuel.
You don't have a street tune & a dyno tune.
A dyno is a tuning tool, if someone had a car they raced on race fuel and also used it say as a weekend driver, they may have a twin tune set up in the computer so they could switch to pump fuel.
You don't have a street tune & a dyno tune.
btw i know exactly what i was trying to say and couldn't have said it better. a dyno tune is a dyno tune, then you tune it some more (tweak it) so it has good street manors as well, not just all out power tuning.
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From: Land of the FOID
Uhhh...I can't imagine how much more they would charge me for a street tune also, $450 is enough. If they can't sort it out after a second trip back I'll start to get loud. I know several people who have had to go back to adjust certain things when it comes to dyno tuning and I have no problem with that. I just don't like the fact the dude said it was "normal".
It's a well known tuner around here who mainly deals in LSX cars, and I think they are a sponsor here.
It's a well known tuner around here who mainly deals in LSX cars, and I think they are a sponsor here.
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From: Shawnee, OK
well my car was tuned strictly on the dyno and runs 100% perfect cold hot rainy sunny doesnt matter it has perfect street manners and perfect throttle response and WOT response. my tuner is also a badass. the tuner is a huge part of how the car will run and behave that being said i suggest either looking at some of your parameters yourself or get a 2nd opinion from a good tuner or just go ahead and have it tuned somewhere else. i would.
The same terminology Down Under has very different meaning, eg. "Street Tune". He's referring to the usage context, while you're talking about the methodology.
"Two cultures separated by a common language."
And you might also have looked into part-throttle dyno tuning before you fully exposed your own ignorance. Too late.
Guys even the best tuner is going to need hours to tune a car properly, from dialing in the ve table, the maf, timing tables, wot fueling/timing, idle fueling/timing, disabling torque managment, air conditioning tuning, anybody can get a car on the dyno and play with the pe table and timing table untill it makes power.
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It is not normal to do that on cold starts
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From: Land of the FOID
^^ Yeah...he said the cold start issue (dies on cold startup) he can definitely take care of. He just guessed on that because he was tuning a warm engine. I don't know much about tuning but the more I think about it the cold start issue and hesitation until the car warms up could be related.
