I have a turbo 99 si tuned on neptune. car made a bit over 250 at 9.5psi on the dyno. After getting the car home and sheetmetal back together car seems really sluggish. Seems to run good when cool but after driving for a while its really boggy. If u punch the gas it really hesitates. If you ease into boost its somewhat better. Strange thing is that is has more power at lower boost (5psi) than full boost (9.5psi). Nothing changed after getting tuned. Changed the plugs, new gas with same results. My tuner is clueless

 

sheetmetal? elaborate

Do you have a wideband on the car?

 

i took the car to get tuned without the hood bumper or headlights on. It was trailered there and back. Never street tuned just dyno tuned. I dont have a wideband on the car. The plugs did look rather black when i changed them. The tuner checked them occasionally during the tune and they didnt look this black.

 

car was tuned at j-k tuning near carlisle. Ran perfect on the dyno.

 

Without a wideband = bad idea.

Get a wideband or take it back to the tuner to have it monitored on the street using his wideband...

 

why do I need a wideband? The car was tuned with a wideband and ran fine. Nothing has changed since the tune.

 

A wideband is not only a monitoring tool but a troubleshooting tool.

You need a wideband to see what the car is doing. Without one you are blind.

If the wideband reports back correct a/f numbers, then you know the issue is mechanical or ignition related etc.

 

$200 for a troubleshooting tool is pricey. Just seems like something simple to me. How often do honda map sensors go bad?

 

It's not a troubleshooting only gauge....
A wideband is like a heart rate monitor for some one with heart problems. You should have one to make sure everything is running properly...

Honda map sensors almost never go bad.
Simply replacing parts to try and troubleshoot an issue is pointless.

Take the car back to the tuner... Problem solved.

 

i know thats what i want to do. Problem is its 3hrs away and gonna cost me another $400 to be tuned

 

You shouldn't have to pay for a retune when the car was literally just tuned.

This is the #1 problem with this industry. People don't think customer service exists.

Contact your tuner instead of guessing what is going on...

 

i did contact him and he suggested the map sensor could be bad. He stated that the tune couldnt have changed. All i know is the car runs slow as crap and it pisses me off.

 

Call him back. Tell him you want him to throw a wideband on the car and see what is going on.

You paid good money to have the car tuned & you got it home & it runs like crap now. It's called customer service.