Help! Fuel issue: At least I think it may be but I dont know what else to do?

[HuskerNation]

So, finally have a fuel pressure guage that works. At key on, but engine not running I had 40 psi. Running at idle I had 37-38psi. When she started to slow her idle like she was dieing the pressure would increase to about 40psi. I would then give it a blurp of the right peddle and she would catch herself and back to idle and around 38psi.

With that said, I do have the oil pressure sensor behind the distributor unplugged, as I was going to change that thinking it was the problem. Havent gotten it changed but is still unplugged as I kinda buggered up the end of the sensor..... ops!

Ok, So after researching the fuel pressure, there seems to be a lot of differing ideas. (Oh, and the vacuum lines are still connected when I tested the pressure.) So, is my pressure ok? Can I or should I drive with the guage attached & taped to the windshield to see what its doing while driving?

 

[HuskerNation]

Well, if I am checking my injectors correctly for an Ohm reading here is what I got: 13.9, 13.3, 12.7, 16.3, 12.9, 16.3, 15.3, 12.6. So do I have injectors going bad? I read 16.0 as the cut off to stay above on this reading.

however, while I was on the injector near #1 cyl, I saw a little hose maybe 3mm wide outside diameter, broken. It was kind of a hard plastic vs rubber & it was broke where two of these little hoses come together to one. After they came together, then the hose snaked down to the area in front of the drivers side tire. When I traced the other end of the broken connection in the other direction,( part of it snapped off in my hand) and it went to the bottom of the intake plentum at the front of it drivers side.

So am I correct that I may have a vacuum leak from this hose? As for a replacement hose, do I get the same kind and if so from where?

THANKS!

 

[HuskerNation]

I also pulled off each injector's electrical connection one at a time and ran
the engine after each was disconnected. My thought was that if it was a "bank
fire" system and if one shorted then they may all be shorting. Unfortunately it
didnt seem to make a difference at all.

Am I correct in thinking it has a
bank fire fuel injection system instead of each injector firing individually?

 

[Schrade]

Ok, So I finally got a chance to mess with the vette today and here is what I have found out. Fuel pressure relay looks to be good as a new one made no effect. All fuses are fine, gas is less than 2 weeks old.

While I was checking and trying things I noticed that when I turned on the ignition key and listened to the pump activating, my fuel pressure would show 3 lbs. After it started it was showing around 60 lbs at an idle or rough idle. Therefore I pulled the connection off the oil pressure switch behind the distributor on the drivers side and started it. Oil pressure read 80 lbs but she seemed to run completely normal!

I am going to try this again and if it truely is running fine then go and replace the oil pressure switch and drive it a little bit. I will let you all know the final outcome soon.

Looks like you're looking at lots of stuff, and that's good. I think you're skipping ahead too fast tho'.

It's got to go to 40PSI first time, every time. (I'm looking at that now on mine too).

If it's not, then cap the line after the FPR (this tests for leaks in the FPR or in the injectors).

Regardless of where the motor stops in the stroke, the injector pintles close. Like the handle on the garden hose sprayer - the tip shuts it down. Valve train stays open / closed / halfway, where-ever. Injectors close tho'.

After time, the pintles can get electronically worn out, and fail to close. THey let static pressure fall, and worse, let fuel drip into cylinder for the full cycle while running. Chrylser had a big problem with that.

 

[Crazyace909]

Well, if I am checking my injectors correctly for an Ohm reading here is what I got: 13.9, 13.3, 12.7, 16.3, 12.9, 16.3, 15.3, 12.6. So do I have injectors going bad? I read 16.0 as the cut off to stay above on this reading.

however, while I was on the injector near #1 cyl, I saw a little hose maybe 3mm wide outside diameter, broken. It was kind of a hard plastic vs rubber & it was broke where two of these little hoses come together to one. After they came together, then the hose snaked down to the area in front of the drivers side tire. When I traced the other end of the broken connection in the other direction,( part of it snapped off in my hand) and it went to the bottom of the intake plentum at the front of it drivers side.

So am I correct that I may have a vacuum leak from this hose? As for a replacement hose, do I get the same kind and if so from where?

THANKS!

That broken line is coming from a main vacumn port off the throttle body and splits going to the valve down by your canister and the other one goes to your EGR valve switch which opens your EGR valve while running so it is important. The best bet is to buy some vacuum T's or Y's and some vacuum hose and repair or replace it completely if its that brittle. It is a considerable vacuum leak though.

 

[HuskerNation]

Well, no one including myself guessed this one correctly. It was a simple and common problem which a true corvette expert diagnosed over the phone in less than one minute. I was amazed at his accuracy but thank God for it!!!!!

 

[Crazyace909]

Well, no one including myself guessed this one correctly. It was a simple and common problem which a true corvette expert diagnosed over the phone in less than one minute. I was amazed at his accuracy but thank God for it!!!!!

So what was it?

 

[Sierra'sVette]

Really?

I seriously just read this whole thread to find out the problem was fixed without an explanation. You should post the problem, people took their time to help you, you should do the same. Thanks