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Discussion Starter · #1 ·
the other day, i took my trooper on its first trip since i put the true duals on, and on the highway, I will either have a CEL (when its on i can basically watch my gas guage drop), or it would not accelerate at all, it would just stumble. id have it to the floor trying to get up a hill, it would stumble like crazy, then eventually, it would stop, and the truck would just take the hell off!! about 2 seconds later the cel would come on.. so my question is... is it the o2 sensor? the fact i have 1 o2 sensor, and 2 seperate pipes out? i really need this fixed, it was kind of bull**** that i got about 90 miles to a full tank (22.5 gallons).
 

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Wow. That's a different technique to try and get folks to help you out.

I mean even though it is a holiday weekend certainly people ought to put their plans on hold so they can be available to offer valuable advice for free to ingrates.

Here's the deal as I understand it:

The truck ran well and got decent mileage before you had the catalytic converter removed and replaced with a piece of pipe - after that both the mileage and performance are less than optimal.

If that's correct I could take your path and say something witty like "well maybe that wasn't the best idea" and then maybe mention something about thinking of future generations, ozone layer and violation of federal law.

But I'm not like that. I like to help folks - even those who don't deserve it.

I'd ask that you look at the O2 sensor (on a 95 there will be only one) and see that it is plugged in and also ask that you go to AutoZone (or another local parts house) and have them read out the ODB I code being set when the check engine light comes on. Both are easy to do and both are necessary steps for anyone to offer you any useful advice.
 

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What code are you getting for the CEL?

HERE is a link to the Isuzu trouble codes that I just put on the wiki.

Find the connector in this photo, and jumper the 1st and 3rd pins w/ a piece of thick copper wire or a paper clip.



Move the ignition to the ON position without starting the engine.

The dash warning light should begin flashing - one time, a pause, and then two times. It will do this three times to give a code 12 to let you know that it is ready to communicate. After it gives a code 12 three times, it will give any codes stored in the ECM. Count the number it flashes before a pause; that's the first digit. Then count the number it flashes after the pause; that's the second digit. With that code, we'll have a better idea of what is going on.
 

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Wow is this really pmat, or did you give your account to a total douche bag. C'mon man, you know this place better then that.

Everyone with a life left town friday night, or has been knee deep in entertaining since then...

Give us some real details, and accept the fact that maybe your exh upgrade fizzled & needs to be rethought.

~psguardian
 

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All I can say is wow :roll:

I understand frustration; but you have to understand it IS a 3-day weekend, that doesn't happen often, I know for you that probably means fixing your truck.....for me that means spending time with family and dogs that I don't get to see too much during the week.

Including putting in a garden, mowing, planting flowers, etc....heck I haven't even had a chance to fix the fuel line hose leaking on the rodeo for 3 wks yet.

Hang in there....I'm sure someone will be able to assist...I'm at 200k and 15yrs with still the original exhaust system, hopefully I don't have to replace it anytime soon.
 

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I know Paul has been having some serious stuff going on right now, so give him some space, he is on a short fuse, and that is probably the reason for his post.
 

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and the funny thing was it hasnt even been 24 hours since he posted the f**k em lmao.
 

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I was gonna suggest that perhaps now that he has two exhaust pipes from the engine, but only one O2 sensor maybe the computer was trying to adjust for what it sees as a problem.

But given the attitude, I won't bother.
 

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johnnie59 said:
But given the attitude, I won't bother.
Eh, everybody has their days. I'm hoping that this was just a case of having a really rough day or typing drunk or something. Hopefully the OP will be back around in better spirits soon to let us know what's going on.

I was gonna suggest that perhaps now that he has two exhaust pipes from the engine, but only one O2 sensor maybe the computer was trying to adjust for what it sees as a problem.
I'm pretty sure that this model only has one upstream O2 sensor (before the catalytic converter). So, as long as the O2 sensor is clean, plugged in, on the one side, and pretty much the same distance from the exhaust manifold as stock, then the dual exhaust shouldn't cause this issue. Even if the OP deleted the catalytic converter, with only one upstream O2 sensor stock, the computer isn't going to know that. The computer isn't smart enough to know that a pipe is now running from the other side either.

I'd check to be sure that the O2 sensor is plugged in securely. Also, we really need to know what that check engine light is all about. Get us those codes, and I have a feeling that we'll be much closer to knowing what is going on.

Probably not related, but just out of curiosity, has anything been done to the EGR system? I've heard that deleting the EGR valve and pipes can really hurt gas mileage.
 

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jessescott said:
I'm pretty sure that this model only has one upstream O2 sensor (before the catalytic converter). So, as long as the O2 sensor is clean, plugged in, on the one side, and pretty much the same distance from the exhaust manifold as stock, then the dual exhaust shouldn't cause this issue. Even if the OP deleted the catalytic converter, with only one upstream O2 sensor stock, the computer isn't going to know that. The computer isn't smart enough to know that a pipe is now running from the other side either.
Your right of course, but that one sensor was taking readings from both cylinder banks before. Now its only getting readings for 1 side of the engine. So instead of reading 6 cylinders its only reading 3. Its only seeing half of what its looking for. It its looking for say 100 and its only getting 50, this could cause it to send back faulty data and cause other stuff to go bonkers.
 

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johnnie59 said:
Now its only getting readings for 1 side of the engine. So instead of reading 6 cylinders its only reading 3. Its only seeing half of what its looking for. It its looking for say 100 and its only getting 50, this could cause it to send back faulty data and cause other stuff to go bonkers.
I see what you're saying, but that O2 sensor is only detecting the air/fuel mixture. The computer will adjust how lean or rich to keep that air/fuel mixture based on readings from the sensor. I can see where gas mileage might be hurt, and maybe some performance lost, but I don't see where the difference in exhaust flow would create the major stumbling that the OP describes. I still need that MIL code before I can even guess what's going on, though.
 

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Wow, you guys are amazing! I knew folks here were ridiculuosly helpful, and have helped me out big time on several ocassions, but this is truly incredible. This is a lot of support for someone who would have had his account deleted from most forums on the internet. I wish I had something to contribute other than moral support, but man you guys are too good.

Thanks, keep it up, and I hope pmat comes back to get some help, even if it wasn't as quick as he had hoped. I am seriously amazed at the positivie replies in this thread. I really need to make it down to Uwharrie or something eventually. Thanks for giving a guy the benefit of any doubt, we all need it sometimes, lord knows I do.

Good karma to all of you.
 

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MEphenSean said:
Wow, you guys are amazing! I knew folks here were ridiculuosly helpful, and have helped me out big time on several ocassions, but this is truly incredible. This is a lot of support for someone who would have had his account deleted from most forums on the internet. I wish I had something to contribute other than moral support, but man you guys are too good.

Thanks, keep it up, and I hope pmat comes back to get some help, even if it wasn't as quick as he had hoped. I am seriously amazed at the positivie replies in this thread. I really need to make it down to Uwharrie or something eventually. Thanks for giving a guy the benefit of any doubt, we all need it sometimes, lord knows I do.

Good karma to all of you.
He is an established member, and as a personal friend has vouched he's having a bad week, we don't want to disown him. It's like if your best friend snaps at you, you snap back & then help him out. We are pretty much a drama free tight nit group.

~psguardian
 

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Discussion Starter · #17 ·
vanduker said:
If that's correct I could take your path and say something witty like "well maybe that wasn't the best idea" and then maybe mention something about thinking of future generations, ozone layer and violation of federal law.
FYI i went out of my way and spent $135 on 2 Magnaflow universal cats for that exact reason

psguardian said:
He is an established member, and as a personal friend has vouched he's having a bad week, we don't want to disown him. It's like if your best friend snaps at you, you snap back & then help him out. We are pretty much a drama free tight nit group.

~psguardian
bad week? a month sounds more like it! :?
i am sorry for fliping, it just rubbed me the wrong way after spending 2 hrs finding a ride home after my truck ran out of gas, to come home, jump on here hoping someone had a clue as to whats goin on here.. but instead i found my post on page 2 with no replys... again im realy sorry, ontop of whats goin on already, my baby was (and still is) being a piece of ****.
please forgive and or forget my little temper tantrum...
anyways... still have'ent figured out whats goin on....
I should probabily be a little more specific on my setup, the O2 sensor is in the same exact posistion it was before... all i did was take out the Y pipe that connected the manifolds, cut the Y out, welded a plug on the stock exhaust system on the drivers side, where the o2 sensor is.. that side of the exhaust is basically stock except for the cat and muffler, while the passenger side is custom from the manifold back. I had a similar problem before, before i did the exhaust, in town or on the highway, it would just spit and sputter... then take off like a bat out of hell, and 5 seconds later the CEL would turn on.. Replaced o2 sensor, it ran great.. 2 months later did the exhaust.. ran it around town for about a month, then the first time i took it on the highway it did exactly what it used to... and it will only do it on the highway. last trip on the highway was 180 miles, and in that 180 miles, i managed to burn 1 3/4 FULL tanks! But now, Im just getting terrible gas mileage in general. Today i put $35 in it, approx 8? gallons.. reset my odometer, did a little driving today, looked at my trip meter, said 30 miles.. look at the gas guage.. damn things on E! i had no cel, no rough running what soever. Im at my wits end with this damn thing :lol:
 

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No worries man, we still love ya.

So this is a previous issue returning with a vengeance... Have you checked the fuel tank & lines for leaks? Not puddles, but wet lines or a wet spot on the tank. Split seam on a fuel filter or filter connection? Shorted or old injectors? Do you have a spare ECM to try out? or someone you can trade with for a short time to see if the issue follows the ECM?

~psguardian
 

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Discussion Starter · #19 ·
Most lines are new, but there is one im kind of suspicious of. tonight after 2 hrs of sitting i took a screwdriver and pushed open the schrader valve... i got covered in gas :lol: so i am thinking its an injector/ecm issue.. im thinking when i get the cash ill take the injectors out and have em tested.. but until then i *might* have an ecm to borrow.
 

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Cool, looks like you've already started this line of thought lol. Let us know how the ECM swap goes (if you can manage it). If the injectors are old one may have let loose a deposit & jammed itself partly open, so def have them checked out too. Almost sounds like it passed a deposit once upon a time & is stuck on another (kinda like kidney stones for your Zu).

~psguardian
 
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