Newbie here and have a problem!!!!

[foxdenfarms]

Ok newbie here newbie to diesels and the 6.5. I will update my signature as soon as I figure out how to. I have a big problem, my truck is a 1994 c3500 crew cab flatbed, mechanical wastegate, cone filter, lift pump on switch, straight pipes, boost gauge. Motorr has less than 100k it is a documented Jasper engine that was put in at around 95k truck has 174k on the clock now.

Now my problem...
When I bought the ttuck on the way home if I had my foot on the throttle above 1500rpm the SES light would come on the go out when I let off. Replaced the vacuum wastegate with a home made mechanical one, replaced the filter and opened the exhaust and it runs great! ....But...
Under WOT in o/d at 60 or so it kicks back and looses all power and boost and throws code 36
When truck is shut off and restarted it goes away but when all power is lost boost wont go higher than 3 or 4 psi and has no balls. I read up on code 36 and what I am reading just doesn't make sense.

The truck also sometimes when started and placed in gear will not move or rev just bogs and have to put it in neutral and rev it the back in gear and once you're rolling you're good.

Thanks in advance and I will update as soon as I figure it out. I dont have a computer so im working off my smart phone and I have big fingures and a short attention span...hahaha

 

[matuva]

Sounds like you're meeting an overboost situation and go into limp mode. Your "home made" wastegate controler" is probably the culprit...

 

[foxdenfarms]

Sounds like you're meeting an overboost situation and go into limp mode. Your "home made" wastegate controler" is probably the culprit...

The manual wastegate is built with a piece of allthread locking nut with a gm door spring tightened very little peaking boost around 11psi at WOT then slightly jumps when shifts and will level out around 3-5psi at cruising speeds.

 

[THEFERMANATOR]

Set it back to 8 or so to prevent it from seeing a possible overboost condition. Stock the ECM runs about 7-7.5 PSI depending on altitude. An overboost will definatley cause it to pull fuel out in a BIG way and do what you describe.

 

[foxdenfarms]

Ok so I will tone it down a bit and hope it helps, there is nothing worse than pulling 12,000lbs of horses and a trailer tack and people up a 9 percent grade and it kicking back and barely making it to the top. To turn the boost up a bit more will I have to reflash the ecu? How is this done?

 

[WarWagon]

Ok so I will tone it down a bit and hope it helps, there is nothing worse than pulling 12,000lbs of horses and a trailer tack and people up a 9 percent grade and it kicking back and barely making it to the top. To turn the boost up a bit more will I have to reflash the ecu? How is this done?

It isn't common knowledge that the factory equipped turbo is too small and it is the boat anchor keeping you from making it up the mountain grades with any speed. For reference:

http://www.thetruckstop.us/forum/showthread.php?37051-maxxTORQUE-article-on-the-A-Team-Turbo

Couple vendors on here that can help with the tune and bigger turbo. Myself I went from 33 MPH up mountain grades to 55 MPH and gained 3 MPG. The homemade turbomaster, tune, etc are all band aids to the major issue of the factory turbo choking the death out of your engine. Address the turbo and the related items with it: 4" exaust and tune.

 

[Big T]

It isn't common knowledge that the factory equipped turbo is too small and it is the boat anchor keeping you from making it up the mountain grades with any speed. For reference:

http://www.thetruckstop.us/forum/showthread.php?37051-maxxTORQUE-article-on-the-A-Team-Turbo

Couple vendors on here that can help with the tune and bigger turbo. Myself I went from 33 MPH up mountain grades to 55 MPH and gained 3 MPG. The homemade turbomaster, tune, etc are all band aids to the major issue of the factory turbo choking the death out of your engine. Address the turbo and the related items with it: 4" exaust and tune.

This^^^^^^^is so true. Changing out the factory turbo for the ATT with proper exhaust and tune really transforms this engine.