EBPV question

[BIG JOE]

If it was the intake piping, wouldn't it be constant and not stop?

***Not necessarily. If you have a bad I/'C boot, with a hairline crack, or pin hole leak.. as boost builds it will bleed at a certain psi.. then build.. then bleed.

Also this afternoon on the way home from work, It was doing something I hadn't noticed before. After driving about 20 or so miles at highway speed I come in to some stop lights and slower traffic. While driving like this with a steady foot on the throttle, the noise is back but real erratic.

*** see above.

As an example 1/2 second hear it, 1/2 second dont hear it, 2 seconds later hear it for a sec, then dont hear it. Sort of like a morse code pattern.

A though just came to mind, what about a clogged back pressure tube, mount, and/or sensor? What ever is going on, it's getting annoying real fast.

Sorry for all the questions, I'm kinda new to turbo diesels.

Could be a clogged tube.. yul just need to inspect everything as dp said.

No apologies needed. This is how we (you) learn about stuff.

One of the Perks of being a member here ??

 

[DieselDo]

update:

It was a slow day at work, so I went over to a friend of mine place to check my intake piping. after pressurizing the intake piping from the inlet to the turbo compressor, we found and heard no leaks.

Any thoughts?

Definately a perk big Joe.

 

[Dieselpwrdredneck]

try unplugging it and see what happens. plug is up there by the fuel bowl 2 wires. I cant recall you might get a check engine light?

 

[BIG JOE]

try unplugging it and see what happens. plug is up there by the fuel bowl 2 wires. I cant recall you might get a check engine light?

Yep.. Try that.

update:

It was a slow day at work, so I went over to a friend of mine place to check my intake piping. after pressurizing the intake piping from the inlet to the turbo compressor, we found and heard no leaks.

Any thoughts?

Definately a perk big Joe.

When you pressurized the Intake piping.. did it hold a steady static pressure ??

Joe

OBTW.. Do you have a Boost and EGT guage installed ?

 

[DieselDo]

Unplug what, the the valve at the pedestal or the ebp sensor on the front of the engine?

It did hold a static pressure, I don't remember what we pressurized it to though, I think it was like 15 PSI or so.

No, no E.G.T. or boost gauges....yet. That's a planned add on sometime in the future after fuel bowl rebuild, body work, brakes and tires.

 

[BIG JOE]

Unplug what, the the valve at the pedestal or the ebp sensor on the front of the engine?

*** The one on the front of the engine. Drive it. Then the one on the bottom of the pedestal.. and drive it.

It did hold a static pressure, I don't remember what we pressurized it to though, I think it was like 15 PSI or so.

***You need to put about 25 psi on it.

***Is the Red line from the MAP sensor.. connected to the Wastegate accuator ??

No, no E.G.T. or boost gauges....yet. That's a planned add on sometime in the future after fuel bowl rebuild, body work, brakes and tires.

With the erratic performance yer feeling, with no Boost gauge to show turbo pessures... yer best bet at this point would be to have yer 7.3 Scanned.. for any codes. So you can define whats going on, and work on some specifics ?

We're just stabbing around at this point ?

Joe

 

[DieselDo]

Yes, red line is still hooked up.

I'll have the computer scanner for codes this weekend, try to get a boost reading, and retest at 25 PSI.

would a 0 - 30 psi acetylene gauge work for testing boost until I pick up a real one?

What kind of pressures should I expect?


Thanks for your time and input, it's much apperciated.

 

[BIG JOE]

Yes, red line is still hooked up.

***

I'll have the computer scanner for codes this weekend, try to get a boost reading, and retest at 25 PSI.

***

would a 0 - 30 psi acetylene gauge work for testing boost until I pick up a real one?

***Should work, .

What kind of pressures should I expect?

***At idle, no load.. 0.

In gear, normal acceleration: 3-5+ lbs.

At (say) 65mph, level ground: 3-5 lbs.

At speed, putting heavy throttle demand on: +/- 20 lbs.

ALL readings should be Smooth & Steady.. NO needle Bounce.


Thanks for your time and input, it's much apperciated.

No Problem

We love this stuff.

Joe

On edit: You might also check the 2 boots and 4 clamps under the Y pipe that connect to each head intake plenums... are in good shape and tight (all yer boots/clamps are @ 230,000 miles & 14 years old ?)

 

[DieselDo]

A partial update:

scanned the computer with my cheapo scanner as well as one used by ford tech's, both came back with NO codes.

Haven't been able to get to pressure test the intake piping at 20 psi or get a boost reading yet. Found a good place to test boost though, A toll booth up 300 feet in a mile and a quarter, coasting at 30 push back up to 65.

will report back when I have the info.

btw: the boots may have been replaced, the P.O. had some work done when the water pump started to go. I just recently inherrited this truck and finding out it's quirks.

is it ok to test boost at the map sensor?

 

[BIG JOE]

Has this 7.3 been mod'd at all by the PO ?

Yes.. you can T in on the line that runs from the intake Y.. to the MAP sensor. But the MAP data still needs to be communicated to the PCM.. T in, don't isolate the MAP sensor. (at this point ?)

Joe