Engine/Transmission (1994 - 1998) Turbo doesn't come on

[Horse Rider]

I have a 1998 12V Quad Cab 5sp 4X4 Long Bed Gear Vendor Aux Trans Dual gauge Boost & EGT, anyway my Turbo isn't coming in at 1600 RPMS like it use to. It use to be ready to rock & roll when it came on but now it's picking up around 2000 RPMS, by then it's time to shift again. Going to tow my 5th wheel camper to Branson Mo. this weekend. Does anyone have any ideas about some of the things I could look for in getting the turbo to come back in sooner? Thanks!!!

 

[BFaoro]

Leak

Do you have a boost gauge ? You could have a boost leak !

 

[Bhale]

It sounds like a boost leak to me. Look for a stuck wastegate, it may be frozen partially or fully open. One test is to plug the hose from the wastegate to the turbo. The plug is on the front of the tube that comes out of the turbo just after the clamp. Plug both ends and go for a ride.



Next check your hose clamps on all the connections running from the turbo to the intercooler and intercooler to intake to make sure they're tight. It's common for them to get loose and reduce boost.



While your checking the hose clamps, look on the passenger side down near your oil filter. In that general area is an electrical connection for you AC unit and i've seen a few of these connectors right up against the rubber boost hose. As you develop boost the rubber expands and rubs against the connector and wears a hole in it causing a boost leak.



Those are my best guesses, let us know what you find...



Brian

 

[Horse Rider]

Thanks guys, I kind of thought a boost leak too. I removed the boost sensor and put the 1/8" pipe plug back in the intake manifold. But didn't help. That's as far as I have gone. I'll check the rest of the connections tomorrow.

 

[fest3er]

Other than a leak, the other thing that can cause low boost is ... low fueling. Without adequate fuel, you *can't* generate adequate boost. It is possible the AFC is hosed. It's possible the line/tube from the intake manifold to the AFC has a hole or is partially blocked. If the AFC doesn't detect enough boost, it will prevent adequate fuel from being injected to produce the boost.

Just something else to ponder.....

Fest3er

 

[Horse Rider]

Sorry it's been so long answering, been on vacation. I tightened all the hose clamps for the boost lines, drove the truck, no differents. Plugged waste gate line thinking it might be stucked or diaphram broke and loosing boost there, drove truck, no differents. Checked fuel shut off to make sure it was coming fully open and not binding, which it was, everything ok, so far. Then Fest3er hit the nose on the head. I adjusted the star wheel to get more fuel and the truck once again came alive. Now I have my HOT ROD truck back!!!! It really did a nice job towing. Went to Branson, MO. Sure was hilly down there. The truck stood the test very nicely. Seen some very good shows.

Once again THANKS for eveything!!!

Horse Rider

 

[BCFAST]

But I would question..... WHY??? did it all-of-a-sudden start puking out on you... . ? Check you whole fueling system: change the filter, check the line clamps (sucking air?); also put a wrench to the main fuel-feed line connections at the sides of the injection pump. I found some pretty good power by replacing the rubber-coated washers found on either side of the banjo fittings going into and out-of the injection pump. Obviously, they were sucking air... just with age, the rubber coating looked bad.

Brian