94 v6 egr code ?s

[Ghost 94]

I bought a 94 truck with a bad motor (crank broken). I had it rebuilt by a quality shop after putting the motor back in, it had a small miss. I continued to drive for about 10,000 miles and disaster struck motor went bad again. This time it turned out that the #6 piston was badly burnt but the piston skirt had broken. So I had it repaired again and put it back in. However the miss still remained. I have taken to several shops to have it fixed spent too much money and the miss still exists. Even though they keep telling me that it's an egr code but the egr valve is fine. HELP!!!!!!

I've been reading some similiar posts around the net that seem to always point to other pieces attached to the egr. They also talk about the egr exhaust going back into #6 cylinder.

?s
1. will this cause the miss in the motor?
2. How can I determine if this is the problem. (without buying uneeded parts)
3.can I by pass the egr to fix the miss?
4.can someone please guide me through it? (I'm a parts swaper but not a mechanic they are actually skilled LOL!!!)

Thanks,
Chris

 

[2ndGenToyotaFan]

The EGR gas goes back into the top of the intake, and goes to all 6 cylinders more or less equally. The problem with #6 cylinder on these engines is that the passenger side exhaust all gets dumped into the drivers side exhaust manifold right at the rear #6 cylinder, thus it gets cooked pretty good.

Have you checked compression? Is the miss consistent, IE all the time? Try pulling the spark plug wires off of the distributor cap one and a time while the engine is running. Pay attention to how the engine is running (there should be almost no change when you pull the wire of the cylinder that is missing), and see if you can figure out which cylinder is the problem.

And welcome to Mud! Glad to have you, sorry it's under these circumstances...

 

[Ghost 94]

I have not checked compression! But have put new plugs and wires on. The miss is not consistent, when the motor is idling it sounds good (no miss detectable). It doesn't start to miss until you begin to accelerate then it smooths out and reappears when I am getting ready to shift into the next gear (top of the power band). People on these forums refer to a vsv. However they only complain about fuel economy and that the motor runs great. This isn't the case with mine! Could this part create the miss I'm referring to?

I must figure out! At this point I'm so deep (financially) into this truck I could never come close to getting my money out ,by selling. I now need to solve the problem and drive until it falls down in the road LOL!!! . Hopefully 10 years down the road.

When I do a compression test how much compression am i looking for?

Thanks,
Chris

 

[2ndGenToyotaFan]

On a healthy V6 compression should be around 150 psi.

Idles fine, misses while accelerating, then smooths out, then misses again? Do the misses happen at the same RPMs?

 

[Ghost 94]

I may not be explaining it correctly so I just went for a test drive to help me be able to explain.

When engine is cold the miss seems to be a little worse. However yes the miss seems to occur from 3800 rpm and above. Once I accelerate my cruising rpm is around 3000 and then there is no miss or at least not detectable.

This miss is not noticeable to the people that don't drive it reqularly. Wife, son etc. thats how small it is but it drives me nuts and I'm afraid if I continue to drive as is , that I will damage it somehow. It is most noticeable when you have to down shift to keep speed while climbing a hill!

Thanks
Chris