Ok, Went to the dyno today and got real sucky numbers (304RWHP and 387TQ). Truck ran like crap on the way home from the dyno. It had run very strong on the way there.

Investigated and found the larger diameter vacuum line to the EGR completely disconnected and the smaller diameter one barely attached. The guy running the dyno swears he didn't touch them.

Anyone had these blow off before under boost? I guess they could.

He did 4 runs... the first one he said didn't read correctly or something or another. My theory is that the lines blew off then... maybe? That, or he accidentally disconnected them without knowing while he was searching for a place to put the RPM pickup. I saw him in that general area of the engine but couldn't get close enough to see what he was doing.

Anyway, waste of $$$ today. Did learn that the truck runs like crap w/HUGE vacuum leaks :-]

Ideas?

Thanks.

 

are you talking about the DPFE hoses? they normally wont blow off

 

Yup, I have seen that happen. Delete the EGR

 

Hey Raider,
Thanks to my digital camera... here're some pics.

These are pics of EXACTLY how it looked after I left the dyno. The truck obviously ran like ch*t. It did NOT run poorly BEFORE I went to the dyno. Rather fast before I got there I thought :-)


pic 1

pic 2

Thanks.

 

Mine has blown off several times with my turbo setup. One line didn't just come off though, when mine blew both hoses blew off and are somewhere on the highway between here and there.

What I think caused mine to blow was excessive backpressure caused by all my exhaust after my turbo flowing through one single stock cat. I removed this cat and now have no cats and so far no more problem with blowing the lines off. From what I understand they are not your everyday vacuum hoses, but a type of higher heat silicone hose. But mine was forever lost so I used some vacuum hose to make it work again, and I also used some nylon ties on the fittings to hold the hoses in place. It does run like crap when the hoses are disconnected though.


Marlon

 

Hey Streetcruiser...
What do you mean delete the egr? Is it ok to remove it from the truck???

Thanks.

 

There is a kit you can buy that deletes the EGR system completely. I'm not sure it is legal and it might be hard to get it inspected in some areas. But it removes the whole EGR system from the truck and plugs the holes where it used to be.

You can also turn it off forever with your chip and still leave it on the truck where it looks like it still works. I'm not sure what the difference is between the 2 in performance though.


Marlon

 

The EGR system recirculates exhaust thru the engine at all time except WOT. I deleted mine, along with the PCV system. I do not like excess heat in my engine. There are ways to block off the EGR ports, but leave the system on, to look like its there and working. A tuner can turn off the system in the EEC. Dont worry about low speed tip-in detonation, the tuner can compensate for it. Mine did.

 

what kind of exhaust do you have on?...for those hoses to blow off you have to much exhaust pressure...do you have headers on with stock cats?

 

Levi you can turn it off with your Racer software..I would talk to someone first to make sure you have all the parameters set right

 

if you ever need to replace the hoses make sure you get the OEM hoses...the heat will melt them in a hurry...

 

mine have done it twice so far. i'm running long tubes gutted high flows and a bassani.

Will

 

The exhaust system is stock except for the Magnaflow Catback system that's about 20 months old. It's a single pipe after the cats.

You know... I JUST put the water injection on and am getting more boost... voila! I wonder if that's my problem? Opinions on exhaust? I don't like noisy (except when I'm wot).

Levi

 

Raider,
If I turn the EGR off in scalars:system_switches does that in effect disable those vacuum lines connected to it to where I don't have to worry about them anymore?

Levi

 

I don't think those lines are actual vacuum lines. If I understand it correctly, those are some kind of pressure differential lines that open and close the EGR. To my knowledge they don't draw a vacuum from the manifold where they connect next to the throttle body. I "think" they are pressurized from the exhaust system itself. Maybe someone else could explain it bettern than I.


Marlon