Ok guys, gals, and gurus...

I've got one that is got me stumped. I've traveled the Whitebird grade many times and always gone up the grade with my cruise set at 65 and was able to keep 65 or accelerate faster if wanted.

Today I was pulling a small utility trailer 8' x 8' that had a Toyota 4 cylinder engine on it. Small load and light. I couldn't get any faster than 55 MPH at WOT! I can't figure out what is wrong with it... I started out up the grade with cruise set at 65 MPH and it started slowing down to 55 MPH and I canceled the cruise and applied the GO PEDAL and NO GO... It's not a bad apps sensor... Because the boost would climb to 20 PSI and EGT would rise to 1000*F and that's it!

Here is the information I could give...

Boost 17 PSI holding 55 MPH and could hit 20 PSI at WOT
EGT 950 at 55 MPH and 1000*F at WOT
Fuel Pressure 11 PSI at 55 MPH or WOT
Air temp outside was 32-38*F
No smoke...
No error codes...

I'm thinking it's de-fueling... But from what? IAT sensor going bad??? Wild guess...

Please help... This is sad to see my truck not able to pull a little trailer up a 7% grade... At only 55 MPH at WOT!!!!

 

I would say your right about it not getting fuel. I would be more inclinded to look at the MAP sensor then IAT. I can get 23-25 PSI with stock waste gate and see no sign of defueling. I need to block it and see when it happens. Stock injectors I could only get 19 if I ran it to the GOV.

Randy

Might check to see if your tank pulls a vac. after driving. My '99 was and it killed the power. It doesn't have the red cap just an issue with the roll-over check valve I think. I just blocked the cap breather open with a screw.

 

I stopped to get fuel in Grangeville and there was no vacuum in the tank and I've check the sender for a red cap long ago but I don't have it.

1 Vote for MAP sensor...
Any other takers on this problem?

 

How about your exhaust brake stuck on or halfway on?
(first thought)

My truck taking that grade, empty (except my large bottom and standard bed items) can take it 70mph no problem.
EGT will get up close to 1300, and boost will hit the wastegate at 20, drop to 18, back to 20, back to 18, etc, you can hear the engine pulsating as the wastegate opens.

If you're peaking at 1000 degrees, then you've got some fuel issues, IMHO.
(2nd thought)

phox

 

I've had that in the past... The vacuum valve stuck... And there was a lot of black smoke and the pyro goes through the roof... I was only able to go 15 MPH... But that was a long time ago...

Sorry Phox I don't think it is But I will check it in the morning... I'll let you know what I find.

Any other takers?

 

Was the fuel stop before or after the "lack o power" ordeal. Possible fuel quality issue?

 

Are you putting out black smoke at WOT?

 

look were he lives he is in idaho i bet if any thing he is the proud owner of the winter fuel blend.

 

It shouldn't kill the power that much.
Even straight #1, he should be able to pull that hill at the speed limit.


phox

 

if its winter blind and bad fuel it could dont know how old the winter fuel is but it should not be that old but who knows

 

After the problem started...

No smoke... None!

Any other ideas?

 

Ok. Guys, Gals and Guru's

This is what I found so far...

Well Phox I checked the Jake and to be sure that it opening and closing correctly. Yes.. It making the full cycle from closed to open smoothly...

No loss of Coolant or engine oil... (I did notice my vacuum pump seal is starting to weep... )

Now... We are starting to agree its a fuel problem but what? I'm starting to think about changing both MAP and IAT sensors... What would you guys say???

I'm going to head out and at least pull the IAT and check it again... I just cleaned it less than 2-3K ago...

 

Well one of the causes is the fuel filter is dirty...



I got that changed... I got back about 2 PSI of fuel pressure. It improved a bit but still weak to accelerate.

Bump 16 PSI
Idle 13.5-14.0 PSI
Cruise 10.5-12.0
WOT @ 3K RPM 6.0-7.5 PSI

That my current fuel pressure after the filter change...

Any ideas guys???

 

Holy Clogged Filter Batman!!!

WHAP! BAM! BOOM! ZOINKIES!! oops wrong show, but anyway..

If your fuel filter looks like that, how about Air Filter?????

Maybe you are suffocating her...

 

How about this for a air filter... BHAF! & Heatshield...