Engine/Transmission (1994 - 1998) EGT/Turbo Spec's-Advice

[LJHagen]

I'm beginning to get concerned... As I mentioned, all my efforts have been to un-do what a local shop did to my engine a few months ago when they thought by increasing my power (#12 plate) they'd take care of coolant temp fluctuations I was concerned about (you know, the 140-190 problem that almost EVERY 97 has, that isn't really a problem... I didn't know any better during my rookie-Cummins period).



Anyway, I've installed ISSPRO turbo gauge and a thermocouple pre-turbo to try to diagnose what the heck's going on. Besides weak power and black smoke under any type of load, I'm running around 850 degrees and 10 psi on the turbo (wastegate was disconnected at the shop) going 65 mph with NO load. Around town, I try not to hammer it, but things get pretty smokey when I'm acceleration, temp will go from 600 to 900 degrees, and turbo never goes past 20 psi.



Unfortunately, I now live in a place where I can do only limited work on it (maybe an hour at a crack), so I might also be asking for advice on a shop near Loveland, Colorado that somebody might be able to endorse (NOT Engle Automotive, the place that screwed it up in the first place).



Thanks guys!! I sure hope to just get this thing back up to stock!!

 

[bmoeller]

Since the thermocouple is pre-turbo, 900* is just fine. Sounds like it may be a little low, given you have a 215 hp pump.



What did they do to "disconnect" the wastegate? The wastegate is set to around 16-20#, stock.



Was the plate slid forward at all? Was the AFC housing slid forward, it should be. Also, the governor lever may need to be adjusted.



May need to adjust the star wheel in AFC housing. Will need to turn it away from the engine to reduce low boost fueling to cut some of the smoke off idle.

 

[LJHagen]

Originally posted by bmoeller

Since the thermocouple is pre-turbo, 900* is just fine. Sounds like it may be a little low, given you have a 215 hp pump.



What did they do to "disconnect" the wastegate? The wastegate is set to around 16-20#, stock.



Was the plate slid forward at all? Was the AFC housing slid forward, it should be. Also, the governor lever may need to be adjusted.



May need to adjust the star wheel in AFC housing. Will need to turn it away from the engine to reduce low boost fueling to cut some of the smoke off idle.

Good to know the temp is ok! Honestly, I don't know if the AFC housing is forward or not... Does that decrease the post-turbo fuel? I've backed off the star wheel, which seemed to clean up the pre-turbo smoke, although if I go too far back it seems to lose a lot of gusto...

To disconnect the wastegate, they plugged the elbow off the AFC housing and the crossover hose from the Wastegate. I asked for the original fitting back so I could reconnect it (figure since I don't make over 20 psi anyway), but haven't yet... Like I said, I'm just trying to get it as good as stock was (better is fine, of course) and can tow without worrying about cooking anything...

 

[bmoeller]

Unless yours is set up differently than mine, they should've only messed with the one to the wastegate. Should've left the line to the AFC housing alone.



My turbo has a short line from the compressor housing to the wastegate.



This is some good reading- http://www.dodgeram.org/tech/dsl/FAQ/turbo_faq.htm



http://www.tstproducts.com/power_install.html

 

[Vaughn MacKenzie]

Maybe they tried to set the timing and it slipped back a few degrees and it's running retarded? (not saying Stupid Cummins )

 

[ata]

For 97 the 180 hp engine the wastegate is set at 18# on the 215 hp it was set for 24#. With the wastegate plugged you should be able to go over 35# easy. So I would say you have a boost leak somewhere. Without the Air it's going to SMOKE and Not go.

 

[JoshPeters]

It sounds to me like they messed with the boost signal line to the AFC. The AFC is where the star wheel is. Follow that line and make sure it is connected and is getting boost. The only line they should/could have plugged is right at the wastegate. I would get an adjustable boost elbow and reconnect everything. You can adjust so your getting proper boost.



Josh

 

[LJHagen]

Putting it back together

I'll be putting the afc/wastegate line back together this weekend and see what happens. I suspect I'll wind up setting the timing in the near future (I expect this is going to be a little more difficult than twisting a distributor... . )



Thanks for your advice guys!!

 

[bmoeller]

Originally posted by ata

For 97 the 180 hp engine the wastegate is set at 18#

When I was still stock, I could hit 20# after installing a K&N air filter. 18# before, with drop in paper element.