Chimera96

sscott

your tuner would know the 30 lb SVO's and assume he would have advised you run higher FP than the 43.5 (vac line off) so if he didn't you would be better off dropping the FP with your adjustable FPR to get it to 43.5. All for the reasons Fred notes.

If you didn't make any adjustments with the adjustable FPR when you installed it, than it was set "wherever" from the manufacturer and may be more, or less, FP than your car needs and was tuned for.

sscott

Thanks guy's with your quick reply's, I'm going to return to 43.5 psi. Why would the pressure change with the install of the new pump, shouldn't it be the same as the old pump before the old pump went south?

Injuneer

That's why I asked about the brand of the AFPR. Does it look like this?

Aeromotive LT1 Rail Mount Adjustable Regulators | JEGS

sscott

Ok, I adjusted the fpr today with the vaccum line off and it read 50 psi and when I attached the vac line back up it read 44 psi, the messed up part now is that I get an ses light and forgot to bring my laptop to scan it, I am at a friends house, what do you think my problem could be and what are my options to correct it. I think it might be getting too much fuel. When i adjusted it after the fuel pump swap I forgot to remove the vac line and adjusted for 43.5, at my wits end on this.

Chimera96

you pull vacuum line off and plug it. Then adjust FP to 43.5. Put vac line back on FPR it will be around 36-38 (good)

50 psi with vac line off is to high and you will run rich

Injuneer

Unclear.... did it read 50 PSI before or after you adjusted it?

sscott

After, with the vac line removed. The first time I made the mistake and didn't remove the vac line, today I couldn't remove the line on top of the regulator, I ended up removing from the intake but forgot to plug the line. Also, is the cooling fans supposed to run constantly. I probably need to take it to a tuner and find out whats going on, I'll have to scan tomorrow and see what the ses light is about.

Injuneer

Some codes turn the fans on full time.

Not sure what the tuner is going to be able to do about the fuel pressure regulator not being adjusted properly. Why didn't you adjust it with the vac line off the manifold? Plugging the vacuum leak just keeps the engine from stalling. Doesn't affect fuel pressure.

FQuick page indicates you have a BBK AFPR. Is that correct? I never saw one. If the tuner didn't adjust the flow rate for the SVO's lower flow rating pressure (39.15 PSI), at 50 PSI no vacuum you are running 13% extra fuel.

sscott

At this point what are my options on getting this issue resolved to get back to normal?

Chimera96

This

pulling another vac line instead of the one on the FPR won't work as you are still pulling vac from FPR leaving it on.

I don't know why you can't pull the small rubber vacuum line elbow from FPR but that is what you need to do. It helps if you do plug it, vac line not FPR nipple, with something as the car will idle better.

Then just adjust the fuel pressure down to 43.5 PSI with the vac line off. Once done just connect it. Your FP will read lower with line connected (normal)

However as mentioned if your PCM has not been tuned for the 30 lb injectors...you will run rich

Injuneer

I interpreted when he said "I ended up removing from the intake but forgot to plug the line." he meant he pulled the fuel pressure regulator vacuum line off the nipple on the intake manifold. That would be OK. But of course no need to plug the line - would have to plug the nipple.

And it has to be tuned for 30 #/HR SVO injectors, which will actually flow 31.6 #/Hr at 43.5 PSI.

I'm not sure why this is so complicated.... I thought what we were recommending was pretty clear. Guess not.

Or maybe we are not understanding you. Are you saying that no mater what you did the second time, with the vacuum line off, you were unable to reduce the fuel pressure below 50 PSI. That would seem to indicate the fuel pressure regulator is defective, or the return line is plugged. Are you sure it's not an Aeromotive? Never saw a BBK for an LT1.

sscott

What I did the second time was that I didn't block the nipple on the manifold, I'll try it again and block off the nipple. Today I scanned with Scan 94/95 program and tried to see what the dtc was (fans are constantly on and ses light illuminated) and when I tried to check what code it was throwing nothing was listed but when I tried to clear the ses light it went off and the fans stopped for a split second and the fans went on again and the light illuminated and still didn't show a code when I checked again. Now there are three fan relays (all original) should I change all three and see if that solves my dilemma.

Injuneer

Are you sure you set Scan9495 to display codes? I recall something like that being a possible problem. I have never used Scan9495 because I got rid of the stock PCM 17 years ago, but I have reviewed 100's of logs for people. If there is any question on displaying codes, GaryDoug will help you.

And not blocking the intake manifold nipple (for the FPR vacuum line) will not affect setting the pressure. I only suggest that to prevent the engine from possibly stalling, or running extremely rough.

Chimera96

Fred

BWD makes a adjustable FPR for the LT1 (pic), direct bolt on. available through most chain auto part stores

BWD 23065 - Fuel Pressure Regulator | O'Reilly Auto Parts

Injuneer

OK.... but I was looking at his FQuick link in his signature to see if it has a bit more info than in his skimpy "signature":

http://www.fquick.com/garages/Chevro..._SS/1997/6642/

I've asked him twice now about the brand of the AFPR, and still no clear response. Seems to be a one-way conversation - I ask, and get no answers. Not sure how I can help beyond that, so I'll drop out and let someone else figure it out.