VPC question - car running VERY rich [Archive] - DSM Forums: Mitsubishi Eclipse, Plymouth Laser, and Eagle Talon Forum: DSMtalk.com

: VPC question - car running VERY rich

10-11-2002, 07:56 AM
Hi Everyone.
I have a *friend* who's installing a VPC w/ 550 chip in his 99 GSX. We put it in the car, but the car is running rich no matter how much we try to lean it out. Idle was really erratic at first jumping back and forth from 300 - 500 rpm's, but we finally got that under control and running at about 750 rpm's. It's not the head unit because we put it in someone else's car and it works fine. If you need any more info, I'll happily post it.

FPBig 28
RC 550's
Walbro 255
GReddy bov



10-11-2002, 08:06 AM
Try an Adj. FPR. The base fuel pressure may be too much. Other than that I don't know shit about the VPC so I'm usless.

10-11-2002, 08:15 AM
Not useless at all! That's funny you say that because I was just asking someone if that's what it could be.....lets see what everyone else thinks.


10-16-2002, 02:20 PM
Anyone? :(

10-16-2002, 02:33 PM
VPC is very sensitive to intake pressure so you will want to be sure the base fuel pressure is right. Also, have you tried playing the the VPC settings? Try lean the idle knob as much as possible and the gain knob will also affect the idle. If you lean out on the idle knob to say -8 and then you rich the gain knob to +2. The idle setting is actually -8+2 in this case. I found that out because I was trying to lean out on idle but rich things up on the gain and my idle became rich again. VPC usually idle rich from what I have heard so far. Also, the response has to be set all the way on the rich side for the tip-in to work properly.

10-16-2002, 09:01 PM
Maybe there just aren't enough stickers on the car :confused:

But seriously, try an adjustable FPR like everyone else said....your base fuel pressure is probably waaaaay to high.

10-17-2002, 07:58 AM
Where would you get the idea that the car has lots of stickers? :dunno:

Anyway, thanks for the advise everyone. :tree:

10-18-2002, 09:46 AM
Originally posted by dsmtrick
Where would you get the idea that the car has lots of stickers? :dunno:

Anyway, thanks for the advise everyone. :tree:

Geeez, Robin, take a joke, will you :P:D

10-18-2002, 10:59 AM
Sorry Jim. http://www.gamers-forums.com/smilies/otn/sad/1Cry.gif


10-19-2002, 07:36 AM
Moved to Electronics Tech...