A Few Questions....Please Help!

[DoWork]

Well guys, I think I may have narrowed down the issue with my car, but I wanted to run my thoughts/feelings past you guys and get your opinions. I'm sick of throwing parts at this thing, and my "toy" fund is getting lower. I really just want to enjoy my car, so, be honest, and tell me what yall think.

A little background first:

My car has a sumped stock fuel tank, and is using a Bosch 0 580 254 984 pump. I talked to the guy who built my car for the previous owner, and he said he was a cheap ass. Long story short, when the sump was welded on, and the tank was blasted for re-finishing, it was done with the filler cap off, and I ended up with a bunch of crap inside my tank(prior to me owning it). I guess dude got sick of spending money on aeromotive inline filters, and stuck a plastic carb style filter in the line. Well, the pump made quick work of the filter, and is drawing fuel AROUND the element, instead of through it. My thinking is that some of the crap in the tank made it through, and the pump is shot.

As the car hits boost, I can see fuel pressure plummet. I have it set to 43lbs line off, and it comes down to the 40-41 range line on. I have re-done all the vac lines, and replaced the rubber vacuum boots on my regulator. The car looses pressure so fast that the most boost I have seen out of it is around 2lbs.

Here are my questions:

Do you think the pump is shot for sure? I know it is REALLY loud, and sometimes changes pitch at idle.

Is there a chance I have a bum regulator too? I was always told a bad reg would spit fuel from the vac fitting with the line off. Mine seems to be fine. Is there any other tests I can do?

Is there a different pump you guys recommend? I was told that a 255 would flow enough on my car. Is there any truth to this? Looking at flow charts, the bosch flows about the same in the mid range, but keeps pulling in the upper scales where the Walboro falls off.

I have a Aeromotive 100 micron inline filter for the feed to the pump sitting here on my desk, but I was told to run a 40 micron on the return. Do I need to do this? Any recommendations for that if it is needed?

I was thinking about having my tank cut open, cleaned, and sealed. Is this the way to go, or should I just spring for a Fuel cell? Both are about the same price. Is there any reason to do a large cell on a street vehicle? If so, foam, or no foam?

Should I have my injectors tested?


I think thats it for now. Sorry about the long post. I dont have much money to keep futzing with this right now, and I want to have my car for at least part of the summer. Thanks in advance!

-Todd

 

[DoWork]

anyone?

 

[bmackinnon]

As the car hits boost, I can see fuel pressure plummet.

Do you think the pump is shot for sure? I know it is REALLY loud, and sometimes changes pitch at idle.

-Todd

I'd pull the filter altogether just to make sure that's not the issue, and if the press. still drops, then Yes, pump is dead for sure... There is a walbro external pump that performs almost identically to the walbro 340 that most of us use.... search the recent racetronix rant/thread and the part number is in there... that's what I would use for an externa if your build isn't extreme... and that assumes you want to remain external... right?

Change the pump first, cause it's definitely dead.... I doubt the fp reg is bad... seems to be working to reduce pressure under vac, so it's probably ok... injectors should be ok also... believe your questions will be answered when you change the pump... if not, address them then... :wink:

 

[bmackinnon]

Here's that link to the external walbro model number:

http://www.turbobuick.com/forums/2474410-post32.html

and the guy who said it knows his $hizzle....

 

[DoWork]

Its nothing that I would consider "extreme". Its a 4.1L production block, and a pretty decent sized turbo(not sure of the size, but I know its turbonetics), and full bolt ons(ported intake, TB, headers, small cam, roller rockers, etc...). I was simply going off of what the guy who did the fuel system told me to get. I will deffinately look into this Walboro pump though. I will also try pulling this filter tomorrow and taking the car for a spin. We shall see what happens. And yes, I would prefer to stay external becuase the factory fuel lines are no longer under the car. Thanks for all your help!

 

[DoWork]

SO..............Pulled the fuel pump down out from behind the bumper today to get the PN off it again, and guess what I found! Turns out, the fitting for line(-6) was cracked! I pulled the fitting off, and shoved a conglomeration of steel fuel line, rubber hose, and clamps in its place and pulled out of the driveway. As soon as I hit the road, my foot went through the radiator, and VIOLA'! FP jumped up, car hit boost, back tires blew off, and AWAY I WENT!!!! I COULD NOT BELIVE IT!!!! (sorry for the caps, I'm excited). This was the FIRST time I had felt my car boost since I bought it last year. After repeated jaunts on the skinny pedal, FP started falling again, but I am guessing it was because of my mess that I used to "fix" the cracked fitting. I went today and picked up the parts, and hopefully I can get some wrench time in next week to report back that it is/isn't fixed. I must also add, after we pulled the cracked fitting and "fixed" the leak, the pump was almost silent. This leads me to belive its still good. Am I right?

 

[Razor]

Question is if the car is run on pump gas 93 only your boost is limited. Meaning the power it can make is limited. meaning a stock in-tank 255 Walbro would more than cover its needs.

I usually when cleaning up after someones shoddy work go and take the shot gun approach and replace all thats been touched with OEM stuff. yes it costs money, but the end result is you end up with a reliable piece. Not to end up chasing more issues.. especially if the car was ever rear ended..

Sounds like the pump that was added is no better than the stocker at best. And the hose rigs can only be of detriment in the long run.

Enjoy the car, demod the stuff thats not needed or can create issues down the road. Simple.

 

[bmackinnon]

I'm thinking you know already... but be careful about romping on the car with the fuel pressure acting shady.... you obviously have a fp gage you are watching, but are you also watching your 02's and knock retard via a scan tool of some sort? Don't make the mistake, that many uninformed do, of running the hell out of it lean, and blowing the thing up.... expensive mistake... just remindin'... :wink:

 

[DoWork]

I'm thinking you know already... but be careful about romping on the car with the fuel pressure acting shady.... you obviously have a fp gage you are watching, but are you also watching your 02's and knock retard via a scan tool of some sort? Don't make the mistake, that many uninformed do, of running the hell out of it lean, and blowing the thing up.... expensive mistake... just remindin'... :wink:

I know that all too well LOL. I learned the hard way when I was a kid working on the old FWD Turbo Dodges. I do not have a scan tool, mostly because my car is on a FAST system. I need to find an old laptop with a serial port to connect it. I am just going to be careful for now until I am sure its ok. I plan on pulling the plugs when I get back out to where the car is stored to see what they have to say though....

 

[Razor]

I know that all too well LOL. I learned the hard way when I was a kid working on the old FWD Turbo Dodges. I do not have a scan tool, mostly because my car is on a FAST system. I need to find an old laptop with a serial port to connect it. I am just going to be careful for now until I am sure its ok. I plan on pulling the plugs when I get back out to where the car is stored to see what they have to say though....

They sell usb to serial adapters and you can use any laptop.

And..

You can buy an audible or visual knock detector from Caspers.

Question is why would somebody sump the tank, install a FAST, build an engine, and using a weak fuel pump/filter/line setup.

I mean if your going to sump the tank, run -10's to the pre-filter.. a big honking fuel pump(Aeromotive/fuel lab/weldon), and run big lines to the front on an aftermarket regulator and fuel rails.

The real question is how the car was ever tuned using that fuel system. Becuase whatever fuel system is in there hasnt been working correctly .. so the VE tables must be pretty skewed to say the least. Very bad idea to beat on this particular car until its sorted. I would really suggest you redo the fuel system correctly then seek a knowledgeable tuner that works with FAST if your not literate to it. That way you can get the fuel mapping done and then your minor tweaks are on you. Be sure that tuner is Turbo Buick knowledgeable or else .

 

[DoWork]

They sell usb to serial adapters and you can use any laptop.

I just saw that last night. I DID have a laptop that worked, until the screen decided to chit the bed one day about 2 weeks ago

You can buy an audible or visual knock detector from Caspers.

I have an ANS light/audible alarm.

Question is why would somebody sump the tank, install a FAST, build an engine, and using a weak fuel pump/filter/line setup.

I mean if your going to sump the tank, run -10's to the pre-filter.. a big honking fuel pump(Aeromotive/fuel lab/weldon), and run big lines to the front on an aftermarket regulator and fuel rails.

The car had more of a fuel system in the past. I am the 3rd owner, and this is NOT the motor the car had all this done to run. That being said, the guys that owned it before me really did some work to it, and I dont mean that in a good way. I just finished pulling out all the gauges they put in and re-installing new ones. They wired theirs using PHONE LINE. It has been a long process to bring this car back to life. I apologize for me getting excited that I am getting closer.

I do have an aftermarket regulator, and pretty decent sized lines for what my car is.

The real question is how the car was ever tuned using that fuel system. Becuase whatever fuel system is in there hasnt been working correctly .. so the VE tables must be pretty skewed to say the least. Very bad idea to beat on this particular car until its sorted. I would really suggest you redo the fuel system correctly then seek a knowledgeable tuner that works with FAST if your not literate to it. That way you can get the fuel mapping done and then your minor tweaks are on you. Be sure that tuner is Turbo Buick knowledgeable or else .

From what I understand, the fuel system WAS in working order at one point. It was far from perfect then though, and the guy who tuned it did what he could with what he had to work with. I do, however, know that it will need some adjustments. I understand completely what you are saying, and I wouldnt post up this thread asking for help if I didnt feel as if I needed it. All your advice WILL be taken to heart, and I plan on looking into re-doing the fuel system later today. I got a pretty decent stash of line here

 

[bmackinnon]

They wired theirs using PHONE LINE.

Oh... you mean your not supposed to use phone line?? lol... nice...:tongue: