Blue Line Thermal Wave runs crappy

[ronald boda]

My 2004 Blue Line Thermal Wave started blowing black smoke through the exhaust, especially when turning throttle up or down. Runs very rough. Tuned it up. Changed fuel injector. It still runs rough, blows black smoke. It is getting too much gas. ( that's why Jon-Don changed injectors).

So what would cause an engine to send more gas than it needs during operation? It does not have a catalytic convertor, or O2 sensors. When I first start it, it runs extremely rough, wanting to stall! Then I turn up the thermostat and the heat is diverted to the exchanger, the engine runs smoother.

Any ideas?

 

[Jim Martin]

sounds like it is running to rich...... (too much fuel) .this will cause it to run rough and spit black smoke....it will also cause it to stall...you already replaced the injector's......check the fuel pressure regulator next...........

 

[stearnsclean]

sounds like it is running to rich...... (too much fuel) .this will cause it to run rough and spit black smoke....it will also cause it to stall...you already replaced the injector's......check the fuel pressure regulator next...........

how would he check the fuel pressure regulator? is there a specific way to test if its faulty? also where is it located?

 

[stearnsclean]

thats not quite the title you said you were going to post.:

 

[Jim Martin]

how would he check the fuel pressure regulator? is there a specific way to test if its faulty? also where is it located?

he needs to take it in and get it tested...not something I would recommend testing yourself...not to mention...pretty sure most don't have the tools anyway....

 

[stearnsclean]

its been at jon don for a week. they couldnt figure it out.

 

[matt30577]

If it's an engine problem, then I'd take it to a reputable small engine service shop

 

[GRK STL]

To test a fuel pressure regulator, you need to own a vacuum pump. It's a hand held device that when squeezed draws a vacuum and has a gauge on it. You can use the same tool to power bleed brakes.

Basically, on the fuel pressure regulator you have a port that has a vacuum line connected to it. Take the vacuum line off the regulator and attach the hose from the pump. Give the pump a couple squeezes to build 17 inches of mercury of vacuum. Then you wait if the gauge bleeds down the regulator is bad. If the gauge stays constant your problem is elsewhere.

If the gauge bleeds down, you have a hole in the diaphragm inside the regulator which will allow fuel to pass through to the intake and run rich and blow black smoke.
bob

 

[ronald boda]

Thanks for the suggestions. I will ask the tech tomorrow at Jon-Don

 

[magicwand]

did anybody check the air filter?..

 

[Ara Klujian]

On the vortec engine the fuel pressure regulator is located inside the upper intake plenum. Did they change all the fuel injectors? or just one? The CSFI (Central Sequential Fuel Inj)is a GM service bulletin recall. The whole kit should be changed out to the upgraded MPFI (Multi Port Fuel Inj). The kit comes with a new fuel pressure regulator.

Check the fuel pressure with the key in the on position. If the fuel injectors are leaking down you will see the fuel pressure at first read normal then instantly drop down to zero. Leaky fuel injectors will cause hard starts, misfire on one or more cylinders, rough idle, increased fuel consumption and black smoke.

You also may want to inspect & clean the MAF sensor. Inspect the MAP sensor for melted gasket. Usually if the CSFI leaks down the MAP gasket will melt from the flooded intake burning.

 

[Ara Klujian]

If it's an engine problem, then I'd take it to a reputable small engine service shop

This is actually beyond a small engine shop capability. But thats cool.

 

[stearnsclean]

y

On the vortec engine the fuel pressure regulator is located inside the upper intake plenum. Did they change all the fuel injectors? or just one? The CSFI (Central Sequential Fuel Inj)is a GM service bulletin recall. The whole kit should be changed out to the upgraded MPFI (Multi Port Fuel Inj). The kit comes with a new fuel pressure regulator.

Check the fuel pressure with the key in the on position. If the fuel injectors are leaking down you will see the fuel pressure at first read normal then instantly drop down to zero. Leaky fuel injectors will cause hard starts, misfire on one or more cylinders, rough idle, increased fuel consumption and black smoke.

You also may want to inspect & clean the MAF sensor. Inspect the MAP sensor for melted gasket. Usually if the CSFI leaks down the MAP gasket will melt from the flooded intake burning.

his machine has a nissan engine not gm. im not sure if this makes a difference.

 

[matt30577]

Oops, I see what you mean. I assumed it had an engine like a 2cyl kohler, or honda or something like that. Now I see, It has a much bigger engine

 

[Ara Klujian]

y
his machine has a nissan engine not gm. im not sure if this makes a difference.

My bad. Thermal Wave II is the one with the Vortec engine. Too many Waves to keep track of. LOL