Another "wont start" thread (sorry)
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cutlass_455
You are correct on the fuel port. You remove the valve and you can use a meter like this:
http://cgi.ebay.com/ebaymotors/AUTOM...Q5fAccessories
This naturally will only tell you the pressure you have at the rail. I would say if you have a minimum of 45PSI you should be fine to fire the engine and idle it. I believe the LS1 needs 58PSI to run well. If you have the pressure then you have plugged/gummed injectors. Its hard to believe they are all plugged though. I could see 1 or 2 but not 8. How long was the engine in sleep mode?
Danno74Z
You are correct on the fuel port. You remove the valve and you can use a meter like this:
http://cgi.ebay.com/ebaymotors/AUTOM...Q5fAccessories
This naturally will only tell you the pressure you have at the rail. I would say if you have a minimum of 45PSI you should be fine to fire the engine and idle it. I believe the LS1 needs 58PSI to run well. If you have the pressure then you have plugged/gummed injectors. Its hard to believe they are all plugged though. I could see 1 or 2 but not 8. How long was the engine in sleep mode?
Danno74Z
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@Danno74Z, thanks for the link. Is there somewhere else I need to look at fuel pressure??
Does anyone see anything wrong with my fuel setup??
Is it possible that the fuel pressure regulator is blown out. When I run the fuel pump, it sure is loud sounding in the return line.
Does anyone see anything wrong with my fuel setup??
Is it possible that the fuel pressure regulator is blown out. When I run the fuel pump, it sure is loud sounding in the return line.
I didn't know that there was a return line. I knew there was another line that goes to the tank, but that was for the EVAP. It sounds like to me that the fuel pump is priming and then bleeding off the pressure which is why you cant keep it running.
See if you can find someone with a gauge to hook up to your rail and verify your fuel pressure.
See if you can find someone with a gauge to hook up to your rail and verify your fuel pressure.
Teching In
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Cutlass_455
Fuel filter for a 98 Chev 1/2 ton truck? Why not use a filter designed for the 4.8L or for FI. Is this the fuel filter designed for your new engine? This could be part of you problem. On my engine I'm using the 99 or later Corvette filter/regulator. It costs about $50 from NAPA. This unit filters the fuel, regulates the pressure to the rail and returns the fuel it doesn't need back to the tank..........all at the same time. I don't know if this will work for you but it does simplify things. I believe to this day this filter/regulator is on the Vette.
http://www.napaonline.com/MasterPage...ter+%28Gold%29
Danno74Z
Fuel filter for a 98 Chev 1/2 ton truck? Why not use a filter designed for the 4.8L or for FI. Is this the fuel filter designed for your new engine? This could be part of you problem. On my engine I'm using the 99 or later Corvette filter/regulator. It costs about $50 from NAPA. This unit filters the fuel, regulates the pressure to the rail and returns the fuel it doesn't need back to the tank..........all at the same time. I don't know if this will work for you but it does simplify things. I believe to this day this filter/regulator is on the Vette.
http://www.napaonline.com/MasterPage...ter+%28Gold%29
Danno74Z
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98Camarod,
The rail has a 3/8" supply and a 5/16" return, both have the GM style push on clip connections. There is also an evap connection, but that line is cheapy plastic. Keep in mind this setup is 2001, so its a bit older. Ive got a 2006 LQ4 on the stand right now and its got a returnless style rail. I got that engine after I had this 4.8 in the car and almost ready to go.
Im gonna try to hook up a gauge and see what the pressure is. How do troubleshoot if the regulator is dead, what happens if one fails??
Its crossed my mind to try the injectors from the LQ4 in this 4.8 and see if some magic happens. I think they might flow more, so just as a test it might worth it.
Danno74Z,
I was considering using the Corvette FPR, but since my rail is a return style, I was sorta forced to find another solution, and that filter was suitable. If / when I switch to a different setup then I will swap to that FPR, it wont be a big deal when I do it.
The rail has a 3/8" supply and a 5/16" return, both have the GM style push on clip connections. There is also an evap connection, but that line is cheapy plastic. Keep in mind this setup is 2001, so its a bit older. Ive got a 2006 LQ4 on the stand right now and its got a returnless style rail. I got that engine after I had this 4.8 in the car and almost ready to go.
Im gonna try to hook up a gauge and see what the pressure is. How do troubleshoot if the regulator is dead, what happens if one fails??
Its crossed my mind to try the injectors from the LQ4 in this 4.8 and see if some magic happens. I think they might flow more, so just as a test it might worth it.
Danno74Z,
I was considering using the Corvette FPR, but since my rail is a return style, I was sorta forced to find another solution, and that filter was suitable. If / when I switch to a different setup then I will swap to that FPR, it wont be a big deal when I do it.
He would only need that filter/ regulator if he was not using the truck intake/ rails with the regulator built in. The filter he is using for a Vortec style truck is rated at the 58-65psi so he is fine. There isn't much to say now until he gets a gauge on it because we are just pissing in the wind without that info. The only other thing I have ran into OCCASIONALLY is enough air in the system to make it not work for a while at first. I always run the fuel feed line into a 20oz bottle or whatever at first before hooking it to the rail, and then hook it up and run the return into the bottle also to get everything moving. I have dealt with issues like that before where with enough air pockets in the fuel system at first it wont run.
Obviously we need to know the fuel system's working pressure at this point to go any further. At least you are getting close...it will be running in no time.
Obviously we need to know the fuel system's working pressure at this point to go any further. At least you are getting close...it will be running in no time.
make sure before you start pulling anything apart that the '06 injectors aren't the flex fuel ones cause they dont plug in. Just something to think about to save you some time.
Originally Posted by MeanYellowZ
The only other thing I have ran into OCCASIONALLY is enough air in the system to make it not work for a while at first. I always run the fuel feed line into a 20oz bottle or whatever at first before hooking it to the rail, and then hook it up and run the return into the bottle also to get everything moving.
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@ MeanYellowZ,
Thanks for the support, before I hooked the line up to the rail, I ran it into a gas can to flush it and and make sure it was filled. And when I initially ran the pump with everything connected, I had a pretty bad leak on the return line right at the tank, so I know there is fuel all thru there. I have also ran the pump for a quite a while cuz I hooked up HP Tuners and forced it on from the laptop for about 3 minutes all by itself. Im quite sure its purged of air.
Also, the 6.0 has non-flex fuel injectors, just regular style ones. What actually might be a good idea is to swap the rail over and convert the fuel filter to the Corvette one.
I am at work today and probly wont be able to work on it again till tomorrow morning. I wanna get a guage on there so bad to see whats up with this.
Thanks for the help and ideas guys, this is why I like this site so much is guys that lend a hand. Its great having someone to bounce ideas off of.
Thanks for the support, before I hooked the line up to the rail, I ran it into a gas can to flush it and and make sure it was filled. And when I initially ran the pump with everything connected, I had a pretty bad leak on the return line right at the tank, so I know there is fuel all thru there. I have also ran the pump for a quite a while cuz I hooked up HP Tuners and forced it on from the laptop for about 3 minutes all by itself. Im quite sure its purged of air.
Also, the 6.0 has non-flex fuel injectors, just regular style ones. What actually might be a good idea is to swap the rail over and convert the fuel filter to the Corvette one.
I am at work today and probly wont be able to work on it again till tomorrow morning. I wanna get a guage on there so bad to see whats up with this.
Thanks for the help and ideas guys, this is why I like this site so much is guys that lend a hand. Its great having someone to bounce ideas off of.
Since you have already ran a feed and return line and have gone through the steps to have the BETTER type of fuel system (regulator closer to the injectors FTW) I would stay with that. Even if you ever wound up going to a car intake/ rails I would spend the extra couple dollars over the vette regulator and just get a decent aftermarket one and still run the return.
disclaimer: Don't get me wrong guys, there is NOTHING wrong with the vette filter/ regulator, I use them ALL the time, but since he has already ran a return style fuel system, there is no reason to change it.
disclaimer: Don't get me wrong guys, there is NOTHING wrong with the vette filter/ regulator, I use them ALL the time, but since he has already ran a return style fuel system, there is no reason to change it.
I don't know what happens when one totally dies, but pull the vacuum hose off of the regulator and see if any gas leaks out of it, if it does it's bad. That's the only problem I've seen from a truck regulator before.
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Its runs!!!! Hey guys, I got it running this morning!!!!
I took the injectors from the LQ4 and put them in the 4.8L, sprayed a 'helper' fluid in the TB, cycled the fuel pump a few times to prime the rails, rolled for like half a second and fired right up and idled away.
The injectors between the two motors have the same part number (25317628) on them, so thats friggin awesome for....no need to tune for them.
Ive uploaded a vid to youtube, check it out.
http://www.youtube.com/watch?v=4U6CQNR4Sts
I just wanna thank everyone for their help and insight. Ive done a lot of reading on this site to get this to happen.
I took the injectors from the LQ4 and put them in the 4.8L, sprayed a 'helper' fluid in the TB, cycled the fuel pump a few times to prime the rails, rolled for like half a second and fired right up and idled away.
The injectors between the two motors have the same part number (25317628) on them, so thats friggin awesome for....no need to tune for them.
Ive uploaded a vid to youtube, check it out.
http://www.youtube.com/watch?v=4U6CQNR4Sts
I just wanna thank everyone for their help and insight. Ive done a lot of reading on this site to get this to happen.
