Engine/Transmission (1998.5 - 2002) Low Boost, can't find the problem

[azpete]

Originally was running a B1 turbo with DDII's that dynoed at 425hp. Lost the need for speed and black smoke and now into towing. Switched out to a new PDR35-12 and RV 275's. On the first test tow with 9K trailer merging onto freeway to 65mph went to 1500* and max 23lbs. boost. Just cruising temps were 1000-1100 and the slightest grade would go to 1300 and more. Got a pressure testing plug for the turbo inlet and tested up to 20lbs. soaping all the boots and intake manifold. No leaks found. Also tested the actuator witch would start to move at around 18 to 20lbs. I'm out of ideas and any help would be appreciated. Also very little smoke and fuel pressure 16 at idle 12 max load.

 

[NIsaacs]

Do you have a boost elbow on the new turbo?

Nick

 

[azpete]

Not the adjustable elbow. Would it be ok to clamp the hose and do a test run?

 

[NIsaacs]

Not the adjustable elbow. Would it be ok to clamp the hose and do a test run?

Yes, or pull the elbow and use a pipe plug.

Nick

 

[SnoKing]

I wonder if your pyrometer gauge is off. More boost will help but at 23 pounds and RV injectors you should not see those temps. SNOKING

 

[Bob4x4]

I wonder if your pyrometer gauge is off. More boost will help but at 23 pounds and RV injectors you should not see those temps. SNOKING

He also shows an edge comp in his sig-enough to melt pistons any day of the week

 

[azpete]

Closed off the boost elbow. Did a test run empty with the comp on 3-2 peddle to the metal to 80mph and got 32lbs boost 1300*. Hooked up the Toyhauler and set comp to 1-1. Getting to the interstate are a lot of 45mph stop and go roads. Power comes on nice and smooth with that comp setting. Getting onto the freeway ramp up to 65mph takes a bit of peddle but only saw 1200*. Cruising at 1150* really strong headwind. On the turn around set the comp to 3-2 and did a steep on ramp. Only got to 1250* 29lbs but a lot faster to 65mph. Cruised at 800 to 900* with tail wind. I called PDR and they may send me another actuator with a stronger spring but since I can only make 32* boost, may just leave it blocked. Snowking..... I have Snows TowMax water meth on a separate probe and both read the same. Last year just to be sure I even bought another egt gauge just to be sure and still read the same. Will have to sell that one. Thanks for the tip NIsaacs, At least the truck can tow now. Will test some more with the comp settings and will also give the Smarty I have a try.

 

[JR]

Just beware if you plan on stacking the Edge and Smarty your egt issues will be compounded. Too much fuel, not enough air at that point. Make sure to download a tune without timing on the Smarty as the Edge will already be altering your timing. Personally if it was me I would remove the Edge and run the Smarty solo. The Smarty is better tuned for everyday driving and towing than the Edge IMO. It makes more usable torque in the lower rpm range than the Edge which is where you need to be. That is essentially my setup, RVs and a Smarty (stock HX) and I have no EGT issues towing at the weight you listed in your first post. The exception is on long steep grades, but if I keep the rpms above 2200 rpm I can pull 6%+ grades til the tank runs dry.

 

[SnoKing]

Well, I never tapped my pump with the Comp, just run it was a timing box on sub level three. Have it set to 1x1 2x2 3x3 4x4 and 5x5. So what ever main level I set it at that is the sub-level in effect. Has been setting at 3 for years. Tows the 12K+ 5th wheel great. Might give that a try, as it is free. Put a little toggle switch in the tap line so you can turn it on and off. Snoking

 

[azpete]

Thanks for the input. I have never run with the comp and smarty stacked. Always used one or the other. I remember years ago reading that the comp would still add timing or something even when off. Not sure if that is true but installed a cutoff switch anyway. Now that I know my problem was the wastegate opening too early I can fine tune for the best tow settings. Will not be able to get out for a few more weeks to test again. Thanks again for your help and I promise to keep the comp down low when I use it, but sure was fun when I had the big turbo and injectors.