jimmyp

iTrader: (1)

Ok ive got a 98 f-body ls1/4l60e swap. It has the 97-98 vette pressure/return all the way up to the fuel rails. I also have a vette filter/pressure regulator and an f-body fuel pump assy.

I had the computer tuned with the vats and stuff removed so that "should" be set to go. I am also using a street and performance wiring harness.

I have fuel pressure at the connection from my fuel line into the fuel rail. No pressure in the return line. However after several start attempts I figured i would have flooded it but the spark plugs dont show any sign of gas.

so to recap:

-Checked the spark plugs and they are working fine.
-fuel going into the fuel rail but none coming out
-fuel pump seems to be working
-tried grounding the neutral safety switch wire coming from the pcm
-engine had new injectors installed last year(engine never started with them tho)
-injectors are making a ticking noise and you can "feel" something in them when it cranks
-brand new aluminum tank and lines

is it possible that either all the injectors got plugged or maybe there is something wrong with the fuel pressure?

where should I go from here?

thanks

Speartech

iTrader: (14)

I think you need to describe your fuel line plumbing, because you don't use a Corvette filter/regulator AND a 97-98 Corvette fuel rail with regulator. You use one or the other.

It sounds like you have both which would create 2 return lines?? So, your fuel line plumbing may be the problem; or at least needs to be better described in order to understand what you have.

jimmyp

iTrader: (1)

ok.....to start in my tank i have a 99 f-body fuel pump/sender assy. From that I have two lines running all the way up to the engine. The guy I got the engine from had the fuel rail modded from S&P to have the pressure/return lines come straight off the fuel rails...which I believe is the 97-98 vette style???

As for the filter its just a single in/single out filter...might not be the vette style filter I mentioned earlier...those might have the double in from the pump and single up to the fuel rail???

I will go out and get some pictures for you just to be sure.

jimmyp

iTrader: (1)

pics:
tank, ive got two wires wired to it for now. One goes to ground and the other goes to the pcm turn on wire



filter on the supply line:




dual lines continueing to the fuel rails:



fuel rails, I have the pressure line connected to the one going straight to the regulator? and the return coming from underneath it (90 degree fitting):

LS1GMCTruck

iTrader: (2)

JimmyP...Question? Where did you buy those black plastic female fuel line fittings that are connected to your F-body fuel pump? I like those better than the metal versions I've seen. Also the coupler nuts on your fuel rail on the engine that allow you to connect those 90 degree fittings to? Thanks, Gar

jimmyp

iTrader: (1)

i got the fuel pump quick disconnects from the auto parts store. I just brought my pump in and had them order anything that might match up. 3 tries later they came up with those. I think they are considered like a repair kit. I think they were $4 each.
And for the fuel rails, they came with the motor. Im pretty sure you could get them from street and performance though.

LS1GMCTruck

iTrader: (2)

for the input. As far as your fuel system goes...It looks like it's hooked up correctly. Is your filter in & out pointing the right way? Are your hoses on the fuel pump swapped? I'd double check the obvious first, this can get you sometimes. Don't know what else it could be. Gar

jimmyp

iTrader: (1)

ill triple check the lines to make sure they arent crossed and Im not sure on the filter. I set it up the same direction as my dads 99 silverados is, i assume this would be the same idea.

I wonder if I am running into a problem because I am running a dual regulated system?? Both the fuel pump/sender assy and the vette fuel rails have regulators on them, correct?

I cant imagine all of the fuel injectors being clogged, they are brand new.

jimmyp

iTrader: (1)

your right...i do have my fuel filter backwards lol. Im gunna go get messy and flip it around....*crosses fingers*

jimmyp

iTrader: (1)

still no luck...any help is appreciated

V8_DSM_V8again

Check for spark? Are the coils firing...

Swap your lines around at the rail. The pipe coming out the bottom of the regulator is the return line.

jimmyp

iTrader: (1)

spark plugs are producing good spark. I do have the return connected to the one coming from the bottom of the regulator too. Im pretty sure now that its somewhere in the fuel rail thats messing up or that I dont have enough psi for the injectors.

V8_DSM_V8again

Check the fuel pressure. Remove the return line at the tank and put it in a bucket or the filler neck so you can watch your fuel flow...

Check your timing..

Are the plugs firing at the right time...

Its hard to goof a LS reluctor but some cars ave sensors that could be 180* out of phase...

In a swap the injector loom from one cyl bank to the other could be swaped... You would still probably run with a rough idle...

The ignition coils could be miswired too... You know they fire but watch the cylinder to see if it is at TDC when it sparks...

jimmyp

iTrader: (1)

thanks for the tips..i will keep those in mind. however I lifted the entire fuel rail up and there was nothing coming out of any injectors when it cranked. I can hear/feel them trying but nothing is coming out.

I dont even think there is any fuel making it to the return line. I cracked both lines where they connect to the rails and only the pressure side had fuel in it. Is there some way of checking/adjusting the regulator??

jimmyp

iTrader: (1)

is there any way to remove and clean the regulator on the rail? It seems thats my problem now. I may try to hook up the lines backwards to try and flush whatever it is out of the regulator. If that doesnt work Ill have to order a new regulator I guess.

just thinking out loud now but maybe Street and Performance screwed up the regulator when they converted it to a return style rail??

jimmyp

iTrader: (1)

ok new update:
I went out and swapped the pressure and return lines going into the fuel rail. So the pressure was heading into the bottom of the regulator and the return came off the back of it. I swear to god the thing didnt even crank for 1/2 a second and it fired up right away. Oil pressure jumped up to 50psi almost instantly. However it began to idle/rev really high so I disonnected the battery after maybe 30 seconds. Everything sounded good, ok awesome, but I was just worried about how high it was revving.

Any new ideas on whats going on???

crainholio

iTrader: (2)

How many RPMs was it turning at idle?

The PCM typically pulls 1100-1200rpm at cold idle while it warms up, then gradually brings the idle down as the coolant temp rises.

So...report back w/ tach readings.

jimmyp

iTrader: (1)

I dont have a tach hooked up yet but that sounds to me like what it was doing. It started and then revved a little, then just as I was about to pull the plug it began to slowly slow down. Im setting up a way to quickly disonnect the battery so I can turn it off faster just in case. Ill go give it another try.

Still cant figure out why the fuel rail regulator works backwards though.

jimmyp

iTrader: (1)

started it up again. It just keeps revving and slowing down to idle then it revs again slows down etc. Is this just the computer relearning after I had it tuned??? I turned it off after a couple minutes when I noticed some smoke but it turned out to just be the exhaust paint.

Also the block and heads stayed nice and cool however the exhaust was too hot to touch after a minute or two of running. Is this normal??? Possibly just running too rich right now?

jimmyp

iTrader: (1)

Well the surging problem turned out to be nothing really. I just hadnt plugged the hole right behind the tb so there was a vacum leak.

Started right up and ran perfect. Oil pressure was around 40ish psi at idle and up to 50-60psi when i revved it slightly.

Still have to figure out why the fuel line regulator at the rails doesnt work when they are hooked up correctly though???

Oh and thanks for all your help guys, I sure appreciate it!!!