Engine/Transmission (1994 - 1998) Lost 10psi boost?

[JGrover]

I've got a 97 12v 5 speed. Banks twin ram 3 gsk, 4" exhaust, etc Truck has always pulled 32 psi boost. pulled my 9000# boat today. 3rd gear Lots of turbo lag almost stuck at 10psi boost. pulling big hills in 4 hi (gear venders) 2000rpm only 24#s of boost. drop to 4 direct at 2500 rpms I could get almost 30psi egts 1200 degrees. truck has 155k on it. Picked up some marine fuel line today maybe sucking air. Bought the truck new, so this is weird it actually not running right.

 

[KYOUNG]

change your fuel filter!!!!!!!

 

[Signal73]

Boost leak maybe? check boots, Intercooler, wastegate, Intake plenum gaskets... . etc

 

[JGrover]

Fuel filter was 1000 miles ago

 

[Joe G.]

Changing the fuel filter for something like this is NOT a good idea. If you have a fuel supply problem and you change the fuel filter then you will have a hard time priming the filter. It just adds to the difficulty in finding what is wrong. You need to check your fuel pressure on the injection side of the fuel filter. If it's good the filter is ok. If it's not good then check to see what the fuel pressure is on the inlet side of the fuel filter. If it's good there and low at the injection pump then change the fuel filter. The fuel filter is seldom the problem.



Low boost may be something as simple as a loose clamp or a torn boot.



If low boost is the result of a fuel supply problem then you may have some trouble shooting to do. Fuel hoses air leaks are usually the cause. Remember, you can't see an air leak so even if the hoses look good they may be bad. If they are the original or replacement fuel hose used for gasoline you might as well replace them because if they are not the problem this time they will be. Read this:

http://dieselram.com/ubb/ultimatebb.php?ubb=get_topic;f=45;t=000007

 

[JGrover]

Could be the intake. After putting in the GV I could pull my my 9000# boat up the biggest 5 mi climbs at half throttle 4 hi 65 mph 1800 rpm 1100 egts. I then put in the 3 gsk moved the plate forward about 1/8" from the stock position. Banks powerpack plate 265 Rwhp/696 Tq. T(hought I would add some none towing play power). Truck smoked too much under heavy get on ramp take off. Back to the stock position again. Long story short, I pulled the Twin Ram Manifold off like 5 times getting to the plate playing with the power. used the same gaskets. I was positive I wanted a #10 TST plate. I already have the SBC Con OFE clutch installed. Afraid the #10 smokes too much/Runs hot while pulling. Then I may have to back the power down to where my banks is anyway.

 

[JGrover]

Thanks for the imfo. Ive heard online that the return lines go bad. picked up 4' ea of 5/16" and 3/8" fuel line while at the boat ramp. 155k time to change them. Must admit I would rather change the intake gasket. Ive pulled it like twelve times playing with the power. That Banks Twin Ram covers blocks acess to the fuel plate

 

[Joe G.]

The sad part about it is that the twin ram is not doing you any good. From what I have read on here there is no evidence from dyno tests that it increases power at all.

 

[JGrover]

The sad part about it is that the twin ram is not doing you any good. From what I have read on here there is no evidence from dyno tests that it increases power at all.

Actually Banks main selling point on the Twin Ram is they say the #6 cyl can run hot. (not enough air Getting too #6 cyl)The the stock manifold air goes in around the #2 cyl only. Where Banks Twin Ram air goes in between the 2 and 3 cyl and the 5 and 6cyl. And both tubes are massive compared to the stocks only one tube. They say it will make your engine last longer. Hopefully not cook the #6 cyl if I getting carryed away on a long 1300 degree pull. Thank goodness I walk away from the fords before I reach them temps.

 

[2broke2smoke]

had same problem and found it the week before indy ...



took 2 folgers instant coffee red plastic screw on lid ... exactly 3 inchs



put a tire valve in one ...



put them in my intercooler boots ...



one at turbo outlet ... one with valve a the intake horn inlet



20 psi of air later found a leak at the intercooler inlet boot



that cured half my problem



the other was at the wastegate hose ... it fell off in my hand



made me fall in love with my HX-55 all over again ...

 

[Matthug]

Sounds to me like the wastegate is stuck open, or as mentioned before a boost leak like a intercooler boot.

 

[JGrover]

I've got a 97 12v 5 speed. Banks twin ram 3 gsk, 4" exhaust, etc Truck has always pulled 32 psi boost. pulled my 9000# boat today. 3rd gear Lots of turbo lag almost stuck at 10psi boost. pulling big hills in 4 hi (gear venders) 2000rpm only 24#s of boost. drop to 4 direct at 2500 rpms I could get almost 30psi egts 1200 degrees. truck has 155k on it. Picked up some marine fuel line today maybe sucking air. Bought the truck new, so this is weird it actually not running right.

Got my power back Oo. Now only my defroster vents blowing air. All vacuum lines look hooked up. The manual says theres a vacuum line one the intake manifold that ties in with the ac? got the boost gage and the afc. One of the vacuum pump. cruise control goes up to the firewall every thing looks hooked up there

 

[Matthug]

The main vacuum line goes in where the A/C lines go into the firewall. There should be 1 plastic vacuum line, trace that back and make sure it's hooked up and/or not leaking.

 

[Signal73]

Got my power back Oo. Now only my defroster vents blowing air. All vacuum lines look hooked up. The manual says theres a vacuum line one the intake manifold that ties in with the ac? got the boost gage and the afc. One of the vacuum pump. cruise control goes up to the firewall every thing looks hooked up there

Its late for me after a long day but did I miss somewhere what the problem was???

 

[JGrover]

I had lost 10 psi boost. Changed fuel lines, Air/Fuel filter and screen good, wastegate not stuck, A few loose ATS manifold bolts. Changed out Twin Ram gaskets. (Fixed problem) Full throttle uphill in 4 hi (Gear venders) 32 psi at 1200 egt's. Hmmm... . Need more power? Naaaa... . This is safe for towing. During test drive, noticed only my defroster vents working. All vacum lines look hooked up. I bet I melted one with my drop light. Will check this AM.

 

[Bobcat698]

I was down to 32PSI of boost and it seemed like I was hitting a governor at 3500RPM. Changed the fuel filter and have 50PSI of boost again, and 4500RPM again

 

[JGrover]

Found the vacum leak. along the firewall on the main vacum line. Theres a caped vacum fitting i've never seen before hidden behind the wiring at the fuel shutoff relay. Recaped it. All ac/heater vents working again.