Engine/Transmission (1994 - 1998) Help!!!!!!! Serious Loss Of Power And Odd Noise

[onestackdram]

ok i have no idea what the hell happened, last night the truck ran perfect. then this afternoon i went to change the air filter, and then i turned up the preboost star wheel only five clicks past where i had it (about 30 from factory settings) i was just doing it to get a little more smoke for a picture. then i started it up and let it warm up for a while. then i took off, and everything sound fine for a second and then when the my turbo normally really starts to sing i got the weirdest noice (could still here the normal noise of the turbo behind it) the noise sound like the LOUDEST house vaccum cleaner of all time. after checking the air cleaner for debris then i pulled the tubing off the turbo to check for any in the turbo itself. then i thought maybe i had just turned the preboost up too much, so i reset it to where i had it yesterday. then tried it again and same thing. (testing by driving around my block) on the way back to my house the noise stopped and ALL OF MY POWER WENT AWAY it all sounds normal but there is no power at all, and when you get about to 2000 rpms acceration stops and it sounds like it wants to cut out (like if you try to rev it up when its too cold) the whole motor is basically stock so i dont know what else to look at or check. guys im really in bind i dont have the slightest clue what is wrong. if it makes any difference after this happened i noticed that my amp guage is reading about 15 amps so im wondering if its not something electrical but i dont know what. i did change my light switch and plug for the headlights today but i cant imagine their related. ANY HELP IS GREATLY APPRECIATED

 

[HoleshotHolset]

I wonder if your fuel solenoid might be not pulling up all the way... . cheap way to check this is to take it right out of the truck and see if this gets rid of your problem. If the solenoid is wigging out... this may explain your low power (if its not pulling up all the way) and your ampere gauge. I'm not really savvy on the electrics behind the solenoid - but others on this board know it by heart as they've had to deal with it.



Adjusting the AFC will not affect your engine's operating RPM at all... .



Check for intake obstructions..... I've heard of errant rags being left in intercooler pipes that would lodge themselves in the grid heater. This particular engine wouldn't rev past 2k rpm with the rag stuck in there... . all was fine when it was removed.



Hope this helps...



Matt

 

[onestackdram]

i didnt even think of that. i have been fighting the selenoid for a few weeks because the first stage burned out, and ive been planning to just make manual shut off. so maybe i will finally be forced to go ahead and do that. thanks if anyone else has any other ideas for me to check let me know.

 

[HoleshotHolset]

The manual shut-off is the way to go if your OEM setup starts giving you problems.



Let us know the outcome... .



Matt

 

[Extreme1]

Did you check to make sure all your pressurized hoses are still connected? Go from the turbo to the intake manifold and look all the way around each one.

 

[illflem]

AFC diagram may have sprung a leak = no boost.

 

[LRamey]

I tend to agree with Extreme1. The loud sound like a vacuum cleaner sounds to me like one of the boots came partially off and was making the wooshing sound. Because it wasn't all the way off you still have enough boost to have reasonable power. After driving some more the boot comes all the way or most of the way off and now no power.

I had this happen to me once so that's why I think this is the problem. Mine came off at the intercooler. Other then that where would the loud vacuum sound come from along with the normal sound of the turbo?

Just my 2 cents.

Lonnie

 

[R.E. Miller]

Here is a hint.

This is hard to communicate here, but if you mean that your truck starts to miss and carry on like it is cold after 2000 rpm, I would bet that if you pulled out your flow valve and shake it, it will rattle a little, or you can poke the ball inside and feel that it doesn't seat right, or you could hook up a fuel pressure guage to your injection pump, and you would see a lot of spikes, erratic pressure, and pressure that does not meet the min standard at rated rpm... . 25 psi min, and a "good" 25 psi at that, not running all over the gauge. This is just a hunch, but if your fuel shut off is opening all of the way, then I would bet on the flow valve being the next in command, easy fix, common symptoms for the most part.



Hope this helps,

Russell

 

[HoleshotHolset]

Good one Bill... . I was going to say that it might be the line coming from the head that feeds the AFC..... but the AFC diaphragm is a possibility.



Matt

 

[onestackdram]

alright guys i have taken out the fuel seleniod. and no change. then i thought well maybe i had an injector loose and sucking air, nope check all are perfectly tight and at the fuel pump itself. then i thought maybe it was the extreme drop in temperature and my fuel had gotten gelled, so i decided to pull the fuel filter and to my surprise it was crushed so i changed it and added an antigel stuff to it and ran it for about an hour letting it idle for 30 min and driving for 30 min. and again no change. then noticed that when ran clear up to 2000 rpms and a little over (when it starts to cut out and run EXTEMELY ROUGH) that i was getting sparks out of my exaust (i have stacks beside the cab so its easier to see this). it only does this if i try to push it REALLY hard. i cant figure this one out. :{

 

[Stixx]

Sparks out of the exhaust?

wow

 

[onestackdram]

GREAT NEWS EVERYONE I FIGURED IT OUT. and like always for me its the most obvious and simple thing to fix. the boot of the turbo to the cooler (like someone suggested had come off and was just sitting there. i never even noticed it until today i pulled it out of the shop to clean the floor and decided to pop the hood just to check the injectors again and when i got up on the bumper it caught my eye. so i put it back on and re clamped it and took her for a drive. OH MY FREAKIN GOD ITS BACK TO NORMAL. :--) i would like to thank everyone who posted a thought or idea. . they were all great and helped me greatly THANKS AGAIN EVERYONE

 

[illflem]

Suggest you use a torque wrench at least once to get a feel for how tight the clamps need to be, they need to be much tighter than one would normally do by hand --70 in/lbs. Cheap hairspray on both surfaces right before slipping together will help keep it from happening again.

 

[BushWakr - RIP]

Way to go SPARKY ... ... ...



Bob.

 

[HoleshotHolset]

Now you 30+ year old guys have something to do with all those left-over cans of Aqua Net..... you know... . from the HUGE hair rock/metal band era?



Glad to hear it was something simple... . if you had gauges, you'd be able to have a boost baseline... . then if even a small boost leak occurred... you'd see it AND hear it... . Hindsight is 20-20.



Matt

 

[Jeff H]

You did check the rest of the turbo duct right ? ? If not Go back out right now and check the clamps for tightness. Something I do at least once a year.

 

[onestackdram]

yal are not going to beleive this crap. i no sooner get it running again and i run to the feed store and my ever so wonderful NV4500 decides to FREAKING DIE on me. its not the 5th gear crap that happened a month ago. no this time the damn thing just completely died. plenty of clutch goes in gear but just grinds. i have no foward or backward gears. i havent had time to pull it out yet to figure out what the hell is wrong now. i will let you all know what moronic crap is wrong with the damn thing now. sorry yal just venting. im so sick of this transmission i could scream.