Help with my dads truck

[mgoncalves]

Hi all, I am going to visit my parents this weekend and would like to do my dad a favor by "tuning up" his truck. It is a 93 250 4x4 with a 5 speed. He bought it used in 97 with 70,000 and he had the valves adjusted a couple months later, where they discovered that the intercooler was bypassed but we dn't know why. It now has 150,000 on it and is extremely gutless, and I know it should run better because I have driven other first gen's to compare it too. What would you guys do to make it a little more driveable? One other thing I have noticed is that when you hit the governor it pours black smoke, and by pours I mean smoke screen. Any help is appreciated, his experience with his truck is a part of the reason I bought my first Cummins (former powerstroke owner) and would like to help it running along great for him.

 

[BushWakr - RIP]

If the intercooler has been bypassed it is really likely that it has a leak(s). With that in mind and the smoke issue as well, you'll need to really consider getting that IC fixed and back on line.

Once that is done, you can do some twiddling with the pump/timing etc. As it is now, heavy smoke at WOT suggests that it is already getting more fuel than it can burn and you may also have a boost leak in the bypass that has been rigged up. Check all those connections real close to be sure that there is nothing loose/broken/rotten through or whatever.

Also make sure the airfilter is in good shape since it can restrict the amount of airflow and cause a very rich mixture, resulting in low power and smoke. Fuel filter should be changed out as well to eliminated it as a contributory cause to low power and poor running.



Sorry I couldn't be more help on this, but I really think the IC is the first thing to be repaired/checked.



Bob.

 

[glhs]

Just for fun I by-passed my intercooler once with a piece of custom bent piece of exhaust pipe. The results? I gained 4psi boost; but made more black smoke, throttle response (spool up) was worse and power was down.

Fix or replace the intercooler for sure.



Next best and/or cheapest route to eliminate the smoke and increase power; a 14 or 16cm exhaust housing, assuming he is still running the stock housing. .

 

[glhs]

I forgot to mention this the last time.

Like BushWakr said you definitley need to change the fuel filter and air filter. I change my fuel filter every oil change (5,000).



Another possibilty; If some where in the trucks lifetime someone could have already changed to a wastegated turbo and the wastegate could be stuck. Also check for a crushed exhaust pipe. If it still has the stock exhaust it will have a crushed section of pipe above the rear axle. Don't worry about that part, they all came that way from the factory, and it wouldn't cause the problems you described.



Good luck and let us know if you have any success.