Moveing on, Turf I checked the upstream and downstream. They all give me signal. I was asking for other values from engines that ran better than mine last week but never got any. I'm sure my signal's are bad given the fact that she is running rich. The scanner is not picking them up as bed though. I think I'm going to have this engine put on a diagnostic machine soon.

 

the downstreams dont have any affect on inputs to the truck, it's my understanding that they just inform you when your cats have gone south. have you thought about putting your known good rears into the front positions and see if it cleans up the way the truck runs?

 

I had replaced my Y-pipe back in march because the Cats were bad. The O2's were cleaned and tested good. Just a few weeks ago I noticed I was getting 7MPG. I put the scanner on it and it said both banks downstream O2's were bad. I replaced them with spares. I have signal on all the O2's. Right now I have no codes and no check engine light. Still getting 7MPG. I just changed out the engine temperature sensor a few days ago. Thought it was running better, but it is not. From everyones suggestion I should change out my O2's, CATS, Fuel filter, plugs, wires and coils. I might as well get a new engine as well. Here is my theory. The Cause is unknown at the moment. The effect is that the engine is running very rich and flooding with fuel. This is causing excess carbon during combustion which is saturating my plugs and exhaust system. Anymore suggestions that I have not tried?

 

I thoroughly enjoyed this post, and agree with your assessment 100%. Thank you @geek_IM for brightening my afternoon!

For those of you keeping score (I know I am) this is the 2ND time the OP has been called out for brushing off the advice he has asked for...

O2's, CATS, Fuel filter, plugs, wires and coils are HARDLY a new engine. If you've replaced some of those things recently, then cross them off the list and check the things you haven't checked that are on that list...

 

Disconnected! Great another smart !@#. Wait until you have a problem or need a part. I'll be sure to remember your name as well Rob.

 

I as well as others tried to give you help but YOU BLEW IT OFF and that was geek's point. I know you are not a big fan of "facts," but here the copy/paste from your post above :

"From everyones suggestion I should change out my O2's, CATS, Fuel filter, plugs, wires and coils. I might as well get a new engine as well. Here is my theory. The Cause is unknown at the moment."

Why do you expect people to help you, when you respond like this AFTER you ask for help figuring out a problem? If you had a "theory" formed already, why did you bother posting?

And don't worry, I have learned your advice is flawed, I don't have a DI, all my windows work, and I don't want a rainbow colored snorkel, so I won't be calling you for anything.

Best of luck "disconnecting." You were gone for what, all of 3 hours the last time you tried that??....

 

Disconnected from your meaningless bull@#$ on this thread. Go back to the D2 site. You backyard whatever need to understand people from all over the country work in different ways. I have tried everything except the fuel filter change tard. Really would a fuel filter cause flooding. Do you know anything about engines and the way they run? Yes we all have our own theories, but getting other opinions wether we believe them or not is what communication is all about. If I took everyones suggestions I would have a completly rebuilt motor. Oh and you drive a D2, well most of those parts are the same as the D1. Your windows work today. Your sunroof works today. And I will remember the idiots that have nothing useful to post other than bashing. Check all your posts and tell me how many times have you bashed people.

 

Spike confirmed it for me based off of his O2 sensor readings and my readings. Seems like all four O2's are way out of range. Hope the ECU is alright. Thank you to everyone who had positive input in trying to figure this mess out.

 

Took my Rover down to a local shop and put it on a diagnostic machine today. Not the O2's that are causing my problems. Found out that my fuel pressure regulator is not the same type that needs to be on my fuel system. I used my spare 97D1 which was non AEL. Apparently the 97D1's had both AEL and non AEL for that year. I had a feeling about that. Two Y-pipes and 2 O2 sensors, plus an engine temp sensor later.

 

did you do a pressure test at the fuel rail? I've got a "converted" newer style fuel pressure regulator on mine and it runs fine, just not when it's -7 degrees out...

Do the 99s have an IACV on them? if that's black and sooty that can cause nightmares too...