My 97 getting hard start,when starts big black puff of smoke comes out of the tail pipe.
I am running bio 5% plus fuel injector cleaner thnking my injectors might be getting dirty.
I am still getting 20 mpg but when i pull my 5th wheel (10,000) I don't have much pulling power. She is all stock expect K&N air filter. She has 175,000 miles and never had a problem with her until now. Wel expect ASD switch go bad in it.

 

That's interesting 'cause mine is doing the same thing... though I'm not running bio in it. It seems to be loosing prime. It either won't start unitl I crank it several time or it will start and sound like someone pulled some of the sparkplug wires off... 'course it don't have plugs but sure sounds that way. In my case, I am wondering if I am having pump problems or ??? Just changed the filter and that did not fix it.

 

Most common hard start problem by far is a leaking return hose shown in red below.
It can suck air without leaking fuel.
Replace with about 2' of 5/16" diesel rated hose.

 

Bill, as usual, you're my hero. Going to have a look Mon. and see if I can find some diesel rated hose. Looks, from the pic above, a bugger to get to but I can move the master cyl.(like changing the fuel filter). I'll keep you posted and thanks again!
Wayne

 

Thank you. I'll run to the part store tomorrow and get one. I'll let ya know if that fix it.

 

If that doesn't work, my 97 had a small leak in the fuel heater. Since this is on the suction side of the fuel pump it was causing a prime issue as well. My first clue was a slightly melted harnass plug to the fuel heater. I put about 1 psi on the fuel system (used an old fuel cap with a 3/8 pipe threaded into it then put a "T" on the end of the pipe for a fitting to a balloon and the air compressor. The balloon keeps the pressure down so I don't get a bunch of #2 all over the place). The leak was small and I have no idea how bad it could be under vacuum but the more I demanded of the motor the worse the problem got. I removed the fuel heater from the pre-filter/strainer; remove the strainer bowl and up inside is a hex nut/spacer/bolt (7 or 8 mm I think). When you take this out the fuel heater drops off and you can put it back together w/o a heater. Works great up here in western WA but I wouldn't try it in a real cold climate. The balloon on the fuel tank works great for priming after a fuel filter change as well.

 

I just had to replace that line, remove the Fuel filter, makes it MUCH EASIER!

Thanks again to Bill.......

 

i would have ur starters checked my dads truck would have a hard time starting but if you put your foot on the throttle a little it would start right up so he took his starter out and brought it to autozone and he got a new one for free cause he had a 7 year warranty on it. and now his truck starts in less than half a turn and his truck has 198k on it.