My ST is slowly dying engine help needed

[TowTrac]

Well I rolled 225,500 miles today. Replaced spk plugs, ignitions, wires, rear wheel bearings, axles and spider gears.



I have alot of bad symptoms. My engine is sluggest and barley able to pull the truck. rough idle, loud racket on start up, seriously bad valve tap on driver side.

My water pump is making a loud noise and I'm wondering if I should replace it or has it done physical damage to the engine. I can do the work myself but I'm afraid of fixing something only to find out the internals were damaged not just the pump. I have the rough engine idle even after the tune. Also today my oil pressure gauge went crazy and only went up when I stepped on the gas and that lasted for a few miles then the oil pressure gauge totally died and the performance got even worse. I limped home at 35 mph.



My question is, how can I tell if the internals of the engine are shot or if it just parts I can pull and replace. I've had this ST since mile 0 and would love to keep her on the road and don't mind spending a little time and $$. You advice is appreciated.

 

[Kody Budinger]

I had the rough idle problem a few weeks ago and it was my air hose was lose and so basically the engine didn't know where to idle so it got really high then went really low to where it would stall. Oil gauge maybe a leak?

 

[TowTrac]

which air hose? the one that attaches to the air intake. I also cleaned out my throttle body and the sensor on top of it. Thanks for the reply

 

[Kody Budinger]

yes that air hose it solved the problem

 

[EddieS'04]

Also today my oil pressure gauge went crazy and only went up when I stepped on the gas and that lasted for a few miles then the oil pressure gauge totally died and the performance got even worse. I limped home at 35 mph.

I would remove the oil pressure sensor. Install a mechanical gauge. Start it up and verify your oil pressure. If it is too low shut down imediatly. Of course from what you say in your quaote I copied. It could have been low oil pressure and the motor was trying to lock up. Did you notice any temp rise?

If the pressure is good. Replace the sensor. I cant find in my manual what the oil pressure should be.

 

[Vic Sorlie]

In addition to Eddie's suggestion, I'd do a compression test, or have it done. You've put on approx 30K miles a year; that's ten oil changes a year for a 3K guy, maybe six a year on synthetic. What has this Trac gotten, and what kind of oil have you used? How about the other fluids like coolant, ATF, gear lube? From your description it sounds like your engine's shot. If you have a shop you trust I'd spend some money for a thorough diagnosis; you may be at a decision point.

 

[Gavin Allan]

Compression test and cylinder leakdown test will tell you about the mechanical condition of the engine.



Check oil pressure with a mechanical guage as Eddie suggest above.



Then, pull the codes and see what is going on there.





Good luck.