DG'sVette

I've been chasing a intermittent hard start condition in 95 LT1 with 72000 miles on it. I've change the following:

Spark Plugs
Spark Plug Wires
Several Vacuum Hoses
Air Filter
PCV Valve
Fuel Filter (Easier Than I Thought & Heard)

I've checked my fuel pressure & it is with in specs. So I'm guessing my fuel pump is OK & I don't have any leaky injectors. Correct? I have not checked the timing (Don't have the tools yet) or checked to see if the injectors are firing correctly. I'm assuming these are not the problem. I hate to assume anything.

I want to try a new fuel pressure regulator. So, should I go with a OEM replacment of should I go with an adjustable?

Autozone Replacement = $63.99
Summit / Jegs, Aeromotive Adjustable = 154.95

REDC4CORVETTE

Fuel presure should be 43.5 with the vaccum line disconnected idle.
I have found eather stick with OEM or Aeromotive.
The rubber the other regulators have blow out and run fuel into the engine ,happened twice to me before I went to aeromotive.
Are you sure you got the air cleaner on right and none of the ducking to the throttle body is rolled under or not secure?
Is the "o" ring on the gas cap good and making a good seal?
Have you checked for codes?
The computer handels the timing ,you can't adjust it unless you have the new MSD distributor,that can be adjusted +or - 5 degrees.

DG'sVette

I'm sure the air ducting is in tact & secure.

Not sure on the gas cap seal but it looks fine.

No codes.

This is an itermittent problem that has become more frequent than not. It used to be a problem every once in a while & now it is every once in a while that it fires up immediately.

Do you think I should give the regulator a try or look somewhere else? I hate to through money out shot gunning a problem but I'm not a mechanic so I'm giving it my best shot. If I do go with the regulator what is the advantage of the adjustable? Is it worth twice the money?

Any help would be greatly apprieciated.

REDC4CORVETTE

I would invest in tools more then parts.The parts you replace it with can be worse then the part you are replacing.
The gas cap would have to blow air at you when you drive a few miles to check it ,when you unscrew it you should hear a wosh sound.
Do you hear your fuel pump run for a second or two when you turn the key to on possession without starting it.
Does the problem occur cold or hot ?
Have you run any type of injector cleaner through the engine.
I use BG to clean the carbon out of the motor.

http://www.bgprod.com/

DG'sVette

Yes when I unscrew the gas cap it sounds like its unsealing.

Yes the fuel pump runs for a second or two when the ignition is turned on. I checked the fuel pressure & it all checks out to spec.

Problem occurs cold & hot.

I've ran two bottles of fuel injector cleaner through. I believe it was Preston.

Any ideas?

REDC4CORVETTE

I would check all the connectors and clean them.
I would also check the map sensor on the intake to see if the rubber seal is good by removing and clean hole in manifold.

DG'sVette

What exactly is the MAP sensor? What does it do? Here is a pic of mine. Do any or you think I need a new one or can this one be cleaned? Could this be part of my intermittent hard start condition?

CFI-EFI

FIRST. Don't replace ANYTHING until you've tested it, and it tests bad. At this point a factory service manual would be a great asset. It has trouble shooting charts that you can follow to track down the cause of a specific code set, or other operational problems, like hard starting. Why replace a regulator (or not) based on the advice of someone not there to observe it's operation and more importantly, TEST it?

I didn't get the picture, just a box with a red X in. But how do you take a picture of, "What exactly is the MAP sensor? Here is a pic of mine."???

RACE ON!!!

silver & red CE

Rough idle after hard start? If so, both times for me it was the optispark

DG'sVette

Thanks for the help guys.

Where should I go to look for a god service manual?

Also, FYI I cleaned up the M.A.P. sensor & hooked it back it & the car fires right up. The tip that goes into the intake was a little dirty.

Hope I got lucky!

skateparkdave

For a "God" service manual try the King James new international version.

For a good service manual go here...
http://www.helminc.com/helm/homepage...anuals&spell=1

kopbet89c4

The laughter from that made me wake up the dog.

I have both a good Helms service manual and a God service manual for those crappy times in my life.

REDC4CORVETTE

Good one Dave You little Devil .
If you get the repair manuels for your year they have what everything is.I will keep you in suspense on the MAP until you get one,both of them.