95 R Fuel System Issues Continue....

[StillIntense]

Well, the problem that has been discussed a good bit in a previous thread continues. Car still slow to build pressure, hard to start, surges at idle, runs decent once warmed up and will go to full throttle. Only thing changed originally was a new fuel safe cell. Have replaced fuel filter, fuel pump (190 LPH). Pressure drop to zero in about 10 seconds after ignition shut off. Max pressure on gauge steady to 37 PSIG once running.
Regulator is a Paxton, been on the car for years. No visible leaks of fuel at rails, injectors, lines connecting to cell.

On an off chance, what is the voltage supposed to be at the connection to the top of the pump assembly? Is it a full 12 volts?
Any other ideas? I'm gettin' ready to drive this thing off a freakin' bridge....:mj:

 

[93SVTCobra]

I still think the fuel pressure regulator sounds suspect. Do you have the stock one still?

P.S. If you are going to drive it off a bridge there are a few things I need off the car first.....

 

[StillIntense]

Mark, that's a distinct possibility. As mentioned, it is a Paxton regulator put on by one of the previous owners at some point.
However, I'd like to figure out if it's a voltage issue to the pump first. Anyone know what the voltage is supposed to be at the connection for the pump at the top of the cell?
The good news is that if I ever sell this car (and I have NO plans to do so), the new owner will have a lifetime warranty on the fuel system........

 

[svtguy]

You should have battery voltage to the pump when the vehicle is running.


Paul.

 

[svtguy]

Here's how to get the pump to run all of the time without the car running.


http://www.svtperformance.com/forums/showpost.php?p=6885186&postcount=9

 

[Ruslow]

Did this just showup AFTER you installed the bladder?If so then look there.If not voltage to the pump should be battery voltage.Fuel filter was replaced?maybe a pinched line?Am curoius as to the fix[when found]STan

 

[Cobra R Man]

FROM YOUR FIRST THREAD!!!!!!

Quote:
Originally Posted by StillIntense
Not that I have found Gene. Certainly nothing signficant (i.e. no fuel flowing off the top of the cell).

What the he** else could be causing this slow pressure build when the pump comes on and rapid pressure drop when the pump (ignition) is turned off?

Keep in mind that nothing forward of the fuel filter was touched during this whole episode, so I'm not inclined to believe that something suddenly happened to the regulator or injectors (by the way, the regulator is a Paxton and has been on there since before I bought the car).

WTF!?!?!

Mark,

The regulator could be weak, since press. drops right after you turn it off. When I was trying to figuring out my problem, I had to wait 'til the next day for my press. to be down. I think your reg. is losing your press. If you have another one(old or otherwise), I'd change it out just to see if it makes a difference.

Again, $.02

Gene

 

[tomshep]

Yep. I agree with the experts. I would try regulator next.

Tom

 

[StillIntense]

Thanks guys, all great advice. Bottom line: if the voltage to the pump is 12 volts, then the regulator will be replaced. I've been hesitant to mess with the regulator since it makes zero sense that the regulator would mysteriously go bad at the same time that I changed the cell. (Gene, that's the reason that I didn't dive into the regulator already, despite your original good advice.)
Diagrams and everything, you guys are GOOD! Don't worry Stan, when this problem is fixed it'll be on CNN......(I'll post it here). Mark

 

[StillIntense]

PROBLEM SOLVED! (finally)

OK, so finally got the R back to normal: it was the fuel regulator. Bought a new factory replacement regulator (non-adjustable), put it on, and it all works.
Now why in the he$% did the regulator fail at the same time a new cell was put in? Makes zero sense.....
On the good news side, just about all the fuel system is brand new except the lines, rails and injectors. Which ain't a bad thing in a car that gets tracked hard.
Thanks again for all the help folks....

 

[Sargent1]

Wasn't a coincidence. I set the regulator and cell to fail on a 19 month time delay. Or maybe because you decided to work on it without me. oke:

Glad to hear it. I just ordered hot rod parts for the ZO6, time to commit to a track day in late September or early October.

XOXO,

Chris

 

[StillIntense]

I might believe that Chris, except that you're not that organized......
Hot rod parts for the Z06? Does that mean that you are now the proud owner of the "gold chain" starter kit?

 

[Sargent1]

No, it's a ZO6, so it's the uprated gold chain kit. I think GM's 2002 advertising listed it as the "New Jersey" edition. The original owner kept them, so I had to buy a used kit off eBay. Still had chest hair stuck in it....