Nightmare!!

[BoJango]

The gray wire from the 5 pin relay goes to the fuel pump on my Winnebago. I was about to tap into it and run a 12 volt wire directly to it to run the fuel pump. But I stumbled upon the shorted relay wiring harness (pigtail) that the 5 pin relay connects to. Replacing the pigtail solved my problem.

[ransil]

Originally Posted by The horseman

I replaced the fuel relay located in the power box.

Trouble guessing only causes more issues.

Get a voltmeter and a fuel pressure gauge.

Did you pull codes yet?

[THenne1713]

When O2 sensors signal control fuel mixture, I fail to understand how gutting CATS can work at all? Maybe my old age?

[Airizon]

Originally Posted by BoJango

I apologize. It is i who didn't read the original post well enough. I wasn't trying to be a smarty britches. But boy do i feel like one now.

I'm not sure gutting the catalytic converter is wise. I think the engine needs some back pressure to properly perform.

My motor home will not shift if the battery isn't near fully charged. It gets into limbo and that's it. I have the Chevy 454 engine.

Sometimes leaking exhaust manifolds will burn the spark plug wires and cause erratic performance.

Once when mine was running like you described your is, I had to replace a part in the distributor. I think it is called the pick up coil module. This part is partially in and partially out of the distributor. It is an easy job to remove after the distributor cap is removed.

I disagree about not gutting the Cat. I had a 91 Jamboree w/ a 460. My performance kept getting worse and worse until I couldn't pull even a slight hill. Someone steered me in the direction of the Cat being clogged up, so I took it to a muffler shop. Sure enough, the Cat was completely empty. But all of the packing material had clogged up the muffler. The Muffler guy said to put on a new muffler first to see if it would improve. It ran perfect. Lots of power, had plenty of back pressure and passed smog inspection no problem. Never did replace the Cat. Not saying this is the OP's issue but something to look into.

[mikf]

Horseman, did you ever get this fixed?

[THenne1713]

Originally Posted by The horseman

I have a 1995 class c Tioga. When I got back to Fl this winter I decided to take care of the exhaust manifold leaks. Previous owner had replaced the bolts with stainless steel. I ended up having to put two new heads on and a new driver side exhaust manifold. Since I completed the work it has not run good. Was loading up not shifting right and struggling to get 65 while burning more fuel. A few weeks ago I replaced the Throttle positioning sensor. That day it ran like a champ, shifting right and better fuel milage. The next day it was running like a dog again. I have replaced fuel pressure regulator, Egr valve along with the solenoid, idle air control, fuel filter and ecm, map sensor. Last year about this time I replaced the fuel pump. It struggles to get 55 does not shift properly and loses power climbing hills. I also gutted the catalytic converter. I’m also not getting good reading when checking fuel pressure. Any suggestions would be appreciated. The horseman!!

https://www.quora.com/Will-it-cause-...e-in-its-place

[THenne1713]

1) what WERE YOUR READINGS on Fuel Pressure? Yup, even new/ nearly new can be BADDDDDD

[BoJango]

A not fully charged battery will prevent the transmission from shifting.
Mine ran very rich and smoked like a freight train once. It was a bad coolant temperature sensor. it's pretty easy to replace.

[THenne1713]

Good point, also suspect disconnecting battery r]to clear history and losing "drive cycle" info also affects transmission shifting, If I understand correctly... computer has to relearn transmission shift points?