Lumpy Idle after installing Hondata with JRSC ???

00JRSC-SIR · Post by **00JRSC-SIR** » Sun Sep 26, 2004 7:37 pm

Hey guys, i just had hondata installed on my ride.

S200B, 6psi JRSC B16 motor, with RC 440cc injectors, obd2-1 conv and P28Ecu.

The car drives awesome and makes good power!

The only complaint i have is that when you come to a stop or if you are idling the car revs up and down on its own.

My tuner said i need to adjust the throttle position sensor?

Is this correct?

Just looking for some more info on what needs to be done, and if its a common problem?

Post by **Hondata** » Sun Sep 26, 2004 8:03 pm

If the idle speed is high (over 1200 rpm), then the problem is an air leak. Because the injectors are cut at 1400-1800 rpm, the rpm will go up and down.

If the problem is that the engine rpm tends to 'hang' a little over 1000 rpm and slowly come down to 850 rpm, then an adjustment will need to be made in the ROM.

00JRSC-SIR · Post by **00JRSC-SIR** » Mon Sep 27, 2004 10:00 am

Thanks for the reply, where do i start?

the idle goes from 1000-2000rpm when the car is stopped at say a light. Eventually it evens out. Then once you hit the gas, it will go lumpy again.

Where should i check for the air leak ?? Injectors area?

or from the the vacuum hose that was attached to the JR FMU unit?

thanks for the help.

MMIGSR · Post by **MMIGSR** » Mon Sep 27, 2004 5:16 pm

"If the problem is that the engine rpm tends to 'hang' a little over 1000 rpm and slowly come down to 850 rpm, then an adjustment will need to be made in the ROM."
-Hondata

Can Hondata in Torrance make this adjustments or do I have to take my car to a dealer?? I have that problem. First they told me it was an air leak, I couldn't find one so we took the car to Acura and they couldn't find an air leak either. I assume it all comes down to the hondata ecu. Can you guys at hondata do that and do I have to pay if you do???
Thanks

Post by **Hondata** » Mon Sep 27, 2004 5:34 pm

00JRSC-SIR - you have an air leak. Start with the throttle body and screw the adjuster all the way in. Then check that the throttle plate is no being held open with the stop adjustment screw.

MMIGSR - you need to get the idle compensation slider reduced in RomEditor. We don't do that here, but try a dealer close to you.

00JRSC-SIR · Post by **00JRSC-SIR** » Tue Sep 28, 2004 1:50 pm

Thank you for your reply,

i have yet to try what you reccomended, i was just wondering why i would need to adjust the throttle plate, if i never touched it originally? I only started having this problem once the hondata was installed.

I looked around for loose hoses and didnt find any.

Post by **Hondata** » Tue Sep 28, 2004 2:12 pm

Often the amount of air bypassing the throttle is increased a long way out of factory specs to stop the engine stalling. If you test the air bypass as per the factory method (unplugging the idle control valve) then the idle speed should drop to around 650 rpm. If it doesn't do this, then you need to reduce the amount of bypass air. I won't be able to explain why it got like that in the first place, only can tell you what to do to fix it.

00JRSC-SIR · Post by **00JRSC-SIR** » Tue Sep 28, 2004 2:42 pm

thanks for the quick repsonse.

So i should start by screwing the adjuster all the way in.
Then check that the throttle plate is not being held open with the stop adjustment screw.

will that fix my problem?

Or do i need to get the TPS sensor recalibrated. Thats what i have been told by my tuner.

Post by **Spunkster** » Tue Sep 28, 2004 3:25 pm

Follow the helms manual instructions for properly setting idle. THis is the best method for doing this.

You should also use the datalogging to make sure that at idle with the idle set properly, your TPS is reading .49 volts.

00JRSC-SIR · Post by **00JRSC-SIR** » Tue Sep 28, 2004 4:42 pm

Here is a vid clip of what the car is doing.

Im sorry the quality is shitty and dark!

Click for VID or save target as!

Post by **Spunkster** » Wed Sep 29, 2004 9:30 am

That is an air leak. You will just have to take your time and find the leak.

00JRSC-SIR · Post by **00JRSC-SIR** » Wed Sep 29, 2004 1:59 pm

hmmm this is getting frustrating!

i just fixed an air line that goes to my boost gauge thinking that was for sure the problem. However it did not fix the problem.

could the recently installed injectors cause this problem?