05stangguy

My car has alot of the symptoms of vaporlock, and im not sure why. Fuel system: Dual Gt pumps, 42 (or 39? Can't remember) lb/hr injectors, 2 -6 lines, into 1 -10 line (I know, HUGE!!)

Basically, when my car starts cold it, it starts right up, no problems. When it is at full operating temperature, and I shut it down, and try to restart it after 10-15 minutes, it cranks and cranks and cranks, and finally turns over, but runs very lean for a few seconds, almost sounds like a few cylinders start, and then the revs jump up. Also, if I am cruising along in 4th gear, and then drop it into neutral (or push in the clutch) sometimes (not always) the car will bog down to about 300-400 rpms or so, and jump right back up, sometimes doing this a few times. Again, this is all while at operating temperature. All of my temp gauges read normal. If I turn the key to the "on" position on and off 4-5 times (aka priming the fuel pump) this seems to help sometimes, but not always. Anyone have any ideas?

Also, I am in Orlando, FL, and have been to the "well known" mustang shops in the area, and have been EXTREMELY disappointed. It almost seems as though they don't wanna take the time to HELP me at all. All i hear is "oh, well it's race season, and we have a ton of engine jobs lined up" or "kenne bell blower? god, I HATE those blowers!!!!"...well EXCUSE ME, sorry for the INCONVENIENCE. I won't say names, but people locally will know who I am talking about. I Really need some help with my car on some things, bottom line, and I wish someone could steer me in a good direction. Thanks guys

Chris

jerjan

Do you have a fuel pressure gauge? If not I would think that would be the way to diagnose whats going on. You may have an issue with the fuel pressure sensor or fuel pump control unit.

05stangguy

I do have a fuel pressure gauge, autometer nexus. However, it has been acting extremely erratic ever since I got the car. It never goes "low" (when it starts blinking red) however, even at idle, it kind of jumps around a bit, between 5-7 psi. I am not sure how accurate the gauges are, as my vac/boost gauge is off as well. I am only seeing 2-3 lbs of boost according to my gauges, and at idle, my vac is at close to 0, when it should be closer to -18 to -20 from what I understand. That gauge is not acting erratic, however again, I do not believe it is reading right. I doubt I have any vac leaks as the power is always there.

JasperGT

Sorry for this, but this is the first thing I thought of when I read the thread title.

http://www.youtube.com/watch?v=NZU3ckWpCdc

Maybe you could retry loading your tune. I don't have a KB, but one time my car when into limp mode. I pulled over, and re-installed my tune, and it's been great ever since. Just an idea...

jerjan

Hmm... you should have at least 30 psi fuel pressure at idle and more when you get on it. Try checking the vacuum lines at the fuel pressure sensor and where you tied in for your vacuum/boost gauge. Any leaks in this area could be the problem. Also check your boost a pump. make sure the voltage control is plugged in properly to the main unit and the range is set to high on the control.