nd4spd

I have just completed an install of a new 62-1 turbo/1.15 turbine on a South Florida Performance manifold, full turbo back 3" exhaust, Greddy fmic, Haltech E6K controlled, street ported, 87 Turbo II. I have 550cc primaries and 1600cc secondaries. All emissions removed. Car stars and idles fine so I don't believe I have any vacuum leaks or bad seals because the motor has about 3k on it. The car wants to go lean anytime I accelerate and stays there until I start to build boost. Light throttle cruise is fine but any load above that and boom, lean. In all rpm's it stays there until it builds 3 to 4 lbs. of boost where it finally goes to rich. Also, there is tremendous lag and boost doesn't really start building until 5500 rpm. Intermittently, it will go to rich and seam to build power very easily. The meter I am using is cheap so I am only using it for gross changes in a/f ratio and am driving conserative until this lean problem is fixed. Another strange thing, most of you claim your turbine, manifold, or downpipe glow after either normal or hard use. Mine does not. I do not blow any flames either. Thought that info might help. I believe this car should start pulling hard around 3.5k to 4k and do so up to 8k. It does not. I am very frustrated so any help would be greatly appreciated.

nd4spd

Gordon, thanks for the help. Are you refering to the throttle pumps or the vacuum bars before staging. Sounds like your describing the throttle pumps which I will try tonight. Also, if anybody else has any ideas, I forgot to add that I have the ND upgraded fuel pump from RP and the stock FPR.

AnthonyNYC

iTrader: (3)

Now I cant wait to go outside and check my throttle pumps...

lol

Anthony

nd4spd

Well, as exciting as throttle pumps sound, especially outside, it is not the problem. Com'on diagnostic gurus, this can't be that tuff of a problem. Does anybody need additional information? Can a fuel pump or FPR show a problem of this nature?

AggieDave

have you changed your fuel filter?

just somthing to check

dave

nd4spd

The fuel filter has about 1k on it so it is basically new. I did some more driving last night and also some testing. There seems to be a consistant voltage to the fuel pump. This problem tends to happen with throttle tip in or if you maintain a consistant throttle position before boost, it tends to drop off to lean between 3.5k and 4k. Then it is sporadic, jumping to rich intermittantly (it feels way down on power and response at this time, jerking as it jumps to rich). Then as boost builds above 5k or so, goes to rich and finally starts building real power. Very weird.

Roy Johnson Jr

Make sure that the feed line for fuel (coming from your fuel pump) is connected into your fuel rail and not connected to your fuel pressure regulator. This may sound like an impossible thing to happen, but I posted this reply due to a certain dumbass doing this to my car...costing me a rebuild.

waynespeed

As strange as this may seem, you could be running too rich right at the staging bar. When your gauge says lean does it goes all the way rich first then loose power and then goes lean.

what milliseconds are you running right before and right after your staging point?

nd4spd

This issue just came up on the Haltech list too. I believe the last bar before boost is around 6.5ms. It falls to 2.72ms after staging. It is hard to imagine that running real rich can cause it to feel like it is falling on it face but I am will to try anything at this point. Gas mileage isn't good. If 6.5 ms is high, were should I be assuming I still need to tweek it from there.

Maxthe7man

Who's map are you running?
Where do you have your map sensor connected to?
what is your base fuel pressure at 12" vac? it should be 35 psi or there abouts..
Disable any decel cut and closed loop until you get it tuned a little better as well..
If you need a map for 1600's, I can send you mine..Max

nd4spd

I am running one of Hitmans maps because I bought the Haltech off of him. I have tuned it to run and idle very smoothly in the areas where this condition is not present The map sensor is connected to the upper intake where Matt originally had it connect on his web page. I believe he has since changed it. I have data logged and found the vacuum/boost gage and data to be close so no wild fluctuations. Source seems to be stable. I will be checking the fuel pump, fuel pressure and FPR this week. TPS also looks to be linear in its sweep. Decel cut off and closed loop are disabled. I would appreciate the 1600's map if your are willing. I will send you a pm with the info on where to send it.

Thanks to Max, waynespeed, Roy, AggieDave and Gordon for all of your help.