Isf sluggish acceleration
#1
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Isf sluggish acceleration
Hey guys, question for the team. I have a 2008 IS-F. It has been so slow on take off. I went to the 1/8th drag strip and was getting best by g37s with some bolt ons. Which that shouldn't happen. I have a custom intake with afe filter, sikky headers, throttle controller, cat delete, custom exhaust with bullet mufflers. When I ran I was getting 9.1s consecutively with 60' being about 2.3.
The car has been dyno'd and claims to be making about 357 give or take to the wheels and 353tq. I have cleaned the throttle body, used fuel injection cleaner. Changed the intake filter. I'm being told I should atleast be around 390 or so to the wheels. I'm still fairly new to the isf as I've only owned it for a few months. I've checked for vacuum leaks none to be bored as I can see. Is there any other recommendations that anyone can give for me to check. I'm wondering if it could be a fuel pump related issue.
Thanks guys
The car has been dyno'd and claims to be making about 357 give or take to the wheels and 353tq. I have cleaned the throttle body, used fuel injection cleaner. Changed the intake filter. I'm being told I should atleast be around 390 or so to the wheels. I'm still fairly new to the isf as I've only owned it for a few months. I've checked for vacuum leaks none to be bored as I can see. Is there any other recommendations that anyone can give for me to check. I'm wondering if it could be a fuel pump related issue.
Thanks guys
#2
Let's begin with the obvious questions to get them out of the way. What tires and wheels? Was traction control off? A 2.3 60' time seems really high. I only have a borla exhaust with stock everything else and Bridgestone S-04's (stock sizes) and can cut a 2.0 60' with ease and a 1.8 in ideal conditions.
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Let's begin with the obvious questions to get them out of the way. What tires and wheels? Was traction control off? A 2.3 60' time seems really high. I only have a borla exhaust with stock everything else and Bridgestone S-04's (stock sizes) and can cut a 2.0 60' with ease and a 1.8 in ideal conditions.
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I left the battery unplugged this morning for a good hour and still not better even after cleaning the TB
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#12
Have you eliminated all of the other "easy" variables such as: quality of gas, reasons for engine to "pull" timing, proper functioning of the throttle controller? Is your exhaust really sooty? Does the car reach high rpm smoothly and repeatedly (even if slowly)?
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Yes I use bp or shell all the times, all the others you stated are good and yes I got the functioning of the throttle controller, exhaust isn't really sooty. It reaches high rpm fine
#14
The symptoms of a bad fuel pump are irregular idle, hard starting, but most importantly in your case, an inability to "keep up" at higher rpm. If you are not having a sputtering, missing, etc. at high rpm, it would look less likely to be a fuel pump issue. If all of the easy fixes are good, then I'd look at the next level. What is your mileage? How are your spark plugs? Many reported drastically improved performance on replacing high mileage plugs. Are all of your intake connections secure and leak free? Do you have the ability to read engine parameters (techstream, torque, etc.)? Does the potential exist for a brake to be dragging? Do you have a friend from the forum with an ISF that could ride along with you to help you troubleshoot?