Hardcore Idle Surge after installation of MAFT Pro & FMIC

[MaNGiNa24]

Since this problem occured right after the installation of MAFT Pro, I figured it'd be best if I posted here.

So I just finished installing my FMIC as well as my MAFT Pro and now my idle is all messed up.

When the car is first turned on, the rpms raise to about 3000 and stay there for a few seconds till it gets a bit warm, then the idle jumps down to 1500 then back up to 2300 over and over very quickly. My car never did this before and I've got the MAFT settings dialed in exactly as most other people have them. MAFT is running in speed density (map sensor and IAT sensor).

I unhooked the MAP and IAT sensor to simulate running without a maf (limp mode) and the idle jumps down to where its suppose to be and the car stumbles.

Here is the log I have hosted on a friend's server:

http://www.vpperformance.com/session8.zip

I posted on the MAFT Pro boards, but thier tech support is terrible, just takes too damn long to get a response and the car's been off the road for several weeks because of this. If I can't get this resolved soon I'm going to have to look into getting a refund and pick up a DSMlink.

Mods:
Intake
3" TBE
Bullseye vtrim
Custom bullseye O2 housing
SBR Exhaust Manifold
SSAUTO FMIC
Stock fuel everything

 

[44pirate]

I had the same problem when I first installed MAFPRO.
I have a couple of questions for you.

1. You did do a boostleak test?
2. Where does your Vac line run to the 3bar Map sensor?
3. What kind of Vac lines are you using?

 

[MaNGiNa24]

You posted on my thread on fullthrottletech.

Map line is shared with bov line from the top of the intake mani. Replaced it with a single line to eliminate the bov and still same result. I haven't checked for boost leaks though, simply because I don't have a boost leak tester. I'm almost posotive there aren't any boost leaks though. I JUST finished installing the FMIC and everything is using 3 ply silicone couplers and tbolt clamps.

EDIT: And the VAC lines are also brand new silicone lines, tried thicker fuel lines and that made no difference. I also noticed when I pinched the line for the map sensor, the car didn't act any differently.

 

[44pirate]

What kind of vacumn lines are you using?
If you are using those shitty colored supposedly silicone lines, they are terrible unless the wall thickness is bigger then the orifice. Get reugular black vac lines. I had those shitty ones. Try this, get someone to rev your engine to 4000-6000 while you watch under the hood at your vac lines. When he gets off the revs see if they don't suck shut.

 

[Mike Licht]

It sounds link to MAP signal is jumping around. Check it on the display. If it ran good before the front mount. Adding one is not going to make it idle bad. It may lean out a bit but not a bunch

Mike

 

[bmxrider154]

Not sure if you have done this already, but did you adjust your BISS to compensate for the increased air flow? My car did this this past winter after I installed my fmic and maft.

Just and idea.

 

[MaNGiNa24]

I actually figured it out, I let a buddy install my tb elbow and while removing it (checking for compromises in weld) I noticed that half the gasket from the tb was folded into the intake path.

Now it idles great, just rough when part throttle.

Thanks for the suggestions guys.

 

[44pirate]

So did you do a boostleak test after fixing that?

 

[MaNGiNa24]

So did you do a boostleak test after fixing that?

Not yet, I do finally have one made though. Gonna pick up a compressor this weekend