Fuel pressure drop?

[ChrisTR]

Im pretty new to turbo Buicks,so bare with me...

I have an 87 Turbo-T, ta49,42.5 injectors,TT chip,adj. fuel pressure regulator,cam(dont know specs)...15lbs boost

My question is: I placed the fuel pressure gauge on the wind shield,I have 43psi fuel pressure at idle with the line off...If I go WOT,the fuel pressure goes to around 60psi,but falls down when it shifts,but climbs back to 60psi...

Is the fuel pump failing? Im not sure what pump is in the car,I just got it..

I also dont have scanmaster or powerlogger,but they will be the first thing I buy,if the pump isnt going bad.


Thanks for any help.

 

[ChrisTR]

Need help guys,need to know if I should go ahead and order a new pump...

 

[Dabigguy]

The fuel pressure regulator adjusts the pressure according to boost. One extra pound of fuel pressure for each extra pound of boost. 43psi fuel pressure at idle + 17psi boost=60psi fuel pressure at WOT.

I wouldn't get on it too much without some sort of scan tool. If it is a problem with the fuel pump you will soon hurt the engine. The scan tool will help tell you if you have pump issues.

 

[ChrisTR]

I plan on getting a scan tool,first thing,just didnt want to buy one and the fuel pump go out right after..
I guess Ill just limp it around until I can get a scan tool,and go from there.

 

[BlackBandit]

Do you have a boost gauge? (not the stock one, it's junk) if so is the pressure following boost? If so the pump is most liky ok for you boost level. If you don't have a way to verify this you need to get a gauge and as you know a scan tool. Good luck.

 

[ChrisTR]

Sorry,I do have an aftermarket boost gauge...It does seem to follow boost,but it was hard for to try and watch both gauges at once...

 

[ttaowner]

do you have a hotwire kit?

i have had 2 cars that people that repaired the fuel lines with a brass part that they must of used to fix a leaking line.well it caused a huge restriction in the fuel lines .only fix for this is to buy a prebent line from 1 of the vendors.

probably not your problem it won't cost you anything to check!

my 2 cars were repaired from the fuel filter to the front of the car. rear line was fine on both

 

[Slow91z]

Sorry,I do have an aftermarket boost gauge...It does seem to follow boost,but it was hard for to try and watch both gauges at once...

I don't understand...Does your boost drop when your car shifts?? If so, that's wrong and therefore your problem, if the boost stays steady and the fuel pressure drops on shifts you may have a fuel problem.

 

[Dabigguy]

There are a few things that are a good idea to have if you plan on going fast with these cars. You need some sort of scan tool,a boost gauge, fuel pressure gauge and an adjustable fuel pressure regulator. Those are MUST haves.

A lot of people use a Scanmaster, I prefer to use one that logs the date like Power Logger or the Direct Scan.

 

[aminga]

I think you're OK as long as FP is following boost

And you were asking me about Direct-scan vs Powerlogger. PL can log boost and fuel pressure.

 

[Dabigguy]

BTW Chris, I have a Direct Scan that I'll let go for $128 shipped.