Need some advice with fuel pressure...

Turbo PeppeR

New Member
Joined
Mar 7, 2002
I just took my car out of storage a few weeks ago where its been since 1998...When I put the car in storage I had just put on a few mods:te44 turbo,307 fuel pump,adj. regulator,36 lb injectors,atr headers,3" down pipe and exhaust (no cat),K&n filter and pitbull chip..First thing I did after smog/registration was hook up my scanmaster...Running a mix of 100 and 93 octane fuel I went for a pass.....Running 18lbs ,As soon as I get to about 15 lbs I start getting knock....My fuel pressure only climbed about 8lbs when boost starts to climb.
Question:What should my F.P. be set at with the car in park and idling,Do I check with or without vac line connected? When I hooked up my f.p. gauge at idle I was at 65lbs which seems high but I dont know...
BTW,I have a TT chip coming,should be here today....
 
Pull the vac line off while the car is running and set it to 43 psi, reinstall vac line.

To determine if your tune is somewhat on par, you need to do a WOT blast in third gear. Find a suitable area free from danger and get up to cruising speed. You need to find out what your 02 millivolts are at the top of third gear full throttle. You are shooting for 780-820 mv.

65 psi at idle is WAY HIGH. You could be experiencing rich knock. There's also the possibility that there is a restriction somewhere, regulator failure, fuel pump issue.

For starters, just try and get the idle pressure down to 43 (which will be like 37-38 psi with the line hooked back up.
 
Adjusted my f.p. to 43lbs vac line off.Took the car for a pass and seems to knock sooner....The fuel pressure seemed to by climbing with the boost but cant get the car to full boost to be sure it climbs enough.It showed 8.9kn instantly on the scanmaster at approx 12lbs boost.Im going to hold off until I get the chip installed and will get serious about my tuning at that point .Im wondering if its the 307 fuel pump or the 36lb injectors or both! Hopefully my chip will arrive today!
Thanks...
 
No more boost. You have a problem. How old is the fuel? The car has been sitting since 98'?

Spring cleaning is in order. Wait for the TT chip and follow those instructions.

Can you write down your info from the scanmaster at idle after a good warm up?

Post it here.

Was the chip upgraded with the injectors when you put her away?
 
Fuel is good,Ive put about 300mi on the car since registering it.The chip (pitbull) was purchased at the same time as the rest of my mods. I need to look up the spring cleaning article,install the chip and go from there,meanwhile Ill go warm up the car and get some scanmaster data....Thanks for your help.
 
The pitbull chip is (as you know) old technology. I can't remember but I don't think they were "burned" for any particular combo. It was a general map.

The data from the scanmaster won't be a great deal of help, but it will allow a window for us to look into to see if any base stuff is screwy. Then we can help troubleshoot from there.

The Grand National / T-Type / Turbo Regal Buick Spring Cleaning Guide

After 10 years, it's probably good to start over from scratch.
 
Heres my numbers at idle:
390-415
AF: 05
L8: 36
bat:13.8
int: 128
bl: 117
clt: 178
ats:132
R: 725
tps:.42
iac: 08
cc: 186
 
Adjusted my f.p. to 43lbs vac line off.Took the car for a pass and seems to knock sooner....The fuel pressure seemed to by climbing with the boost but cant get the car to full boost to be sure it climbs enough.It showed 8.9kn instantly on the scanmaster at approx 12lbs boost.Im going to hold off until I get the chip installed and will get serious about my tuning at that point .Im wondering if its the 307 fuel pump or the 36lb injectors or both! Hopefully my chip will arrive today!
Thanks...

Does your FP rise # for # with boost?--i.e. 12#boost should be 43 (idle-vac line off) +12=55# FP. You're on the right track--you need to monitor FP (get remote gauge/tape to windshield) during testing...

Also, w/ 65#FP @ idle I'm not surprised you got only another 8# out of it under boost--as 70-72psi is at the "flowing max" for a 307 pump...

I suspect dirty injectors???
 
Yes the FP does go up with boost .Im thinking you may be right about the injectors being dirty maybe from old fuel .Should I try fuel injector cleaner or take them and have them cleaned?Thanks for the advice...
 
Yes the FP does go up with boost .Im thinking you may be right about the injectors being dirty maybe from old fuel .Should I try fuel injector cleaner or take them and have them cleaned?Thanks for the advice...

Sure, you can try FI cleaner first while you're waiting on your new TTwk chip--just stay out of boost (which is not req'd for inj'r cleaning)...

If that helps, I'd then pull injs & send out for cleaning (Old Buzzard/ Chuck Leeper comes to mind...).
 
Might also want to consider joining the the 21st century with a set of HI 60# injectors. This way, you will have a lot of room to grow in the future.

Eric will reburn a chip for any change in combination.

Is the 390-415 number the 02's? If so are they going lower and higher than your posted numbers?
 
Thank you everyone for your help...I recieved my TT chip today and installed in my car.I fired the car up with the hood open and heard a slight hissing sound...Apparently when I replaced my vacuum lines at the block on top of the plenum I used 2 different size lines but theres 3 different sizes...fix that drove the car ...0 knock..:cool:
Now about this chip....wow,I didnt think that I would really notice much,right away I noticed the car idled better, somehow the car runs smoother it even smells different....the car drives better.I guess is what Im saying is Im use to not getting what I paid for, just alittle shocked when I get more than expected,Thanks again everyone and Thanks TT (Eric)...:cool:
 
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