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-   -   transmission? Catalytic Converter? HELP!! (http://www.wranglerforum.com/f210/transmission-catalytic-converter-help-29988.html)

cherokee980 05-02-2009 12:59 PM

transmission? Catalytic Converter? HELP!!
 
Okeveryone, I need some knowledge here.

'05 TJ 6 cyl, Auto -

had been running fine, cranked it up friday morning, left the house and noticed it was shifting funny, and seemed to have a power loss. Jeep will idle just fine, but when you are going, you can mash the skinny pedal to the floor, and nothing. I can't get it above 50mph or so. I checked trans fluid, and it was about a quart low, I filled that up, still the same result. I just don't understand how it goes from normal one eve to problems when I crank it up the next day. Not throwing any codes, no CEL...I am at a loss!! HELP!!!!!

jpdocdave 05-02-2009 02:16 PM

could be clogged cat. you say you can get to 50 or so, how hi do the rpm's get while you are accelerating?

tazmann910 05-02-2009 04:23 PM

maybe some dirt in the fuel line.

Can you give some more details at what happens at 50mph?

Splizblot 05-02-2009 11:41 PM

ya, I agree with jpdocdave. I had similar problem, no power, down shifting alot and could barely make it up hills on the hiway. After doing a bunch of troubleshooting and replacing stuff on the motor I figured out it was restricted exhaust and a new cat fixed it.

Rawkon 05-03-2009 02:24 AM

prolly your cat is clogged, wouldnt hurt to do a trans filter and flush. make sure you use atf 4 if you do

jwm1986 05-03-2009 11:36 AM

Pull out the o2 sensor before the cat and go for a short drive and see if it responds better. That will allow the exhaust to get out more normally to tell if it is the cat or not. Don't expect it to run perfect still but you should have more normal power at least if it is the cat.

bamawheeler 05-03-2009 04:33 PM

CAT ! ! ! I have had the same problem before....

cherokee980 05-04-2009 08:09 AM

Thanks guys. I figure it is the cat as well. I will give it the sawzall treatment one day this week. I'll keep you all posted as to what the result is.

cherokee980 05-04-2009 08:12 AM

Quote:

Originally Posted by jpdocdave (Post 365458)
could be clogged cat. you say you can get to 50 or so, how hi do the rpm's get while you are accelerating?

the RPM's get fairly high..higher than usual anyway. It will not kick into OD the way it is now @ 50 mph (about 3K + on the RPM's)


Taz,
it takes it's sweet time to get to 50 mph, and will not go any faster..it feels like it has lost all power.

jpdocdave 05-04-2009 08:50 AM

clogged cat usually keeps the rpms down, slipping trans the rpm will go up and you won't be going anywhere. clogged cat, rpms are struggling to go up, and you don't go anywhere.

cherokee980 05-04-2009 08:55 AM

Quote:

Originally Posted by jpdocdave (Post 366466)
clogged cat usually keeps the rpms down, slipping trans the rpm will go up and you won't be going anywhere. clogged cat, rpms are struggling to go up, and you don't go anywhere.

Exactly why I am confused as to what the true problem is. I will cut the cat out first and go from there. If that's not it, looks like I will be dropping the tranny!

cherokee980 05-04-2009 02:43 PM

do any of you happen to know the factory exhaust pipe size? when I cut the cat, I gotta put a patch back in.

cherokee980 05-08-2009 08:40 AM

Ok, changed the CC, and still have the same problem....can anyone help?

cherokee980 05-08-2009 08:47 AM

gotta keep this one on top..I need help here

whitebuffalo 05-08-2009 09:49 AM

have you replaced your fuel filter? clogged exhaust acts very similar to fuel starvation.....

cherokee980 05-08-2009 10:45 AM

Quote:

Originally Posted by whitebuffalo (Post 369456)
have you replaced your fuel filter? clogged exhaust acts very similar to fuel starvation.....

everything I have read says fuel filter is "lifetime filter" in tank, and all you can actually replace is the "sock" / strainer on the pu tube in tank

whitebuffalo 05-08-2009 12:37 PM

yeah, i wondered about that. my dodge gasser was the same way.

can you check the fuel pressure at the rail?

03rubi 05-08-2009 12:56 PM

Do you have a check engine light on? I would think that a code should be set in the ECM (computer) if it is running so poorly. However, sometimes it won't turn the light on even if a problem has been detected, it's called a soft code. Simply turn the ignition switch on, off, on, off, on and you should get the codes either as a flashing light or as a number on the odometer. That would be the first place I would go before I started throwing parts at the problem.

cherokee980 05-13-2009 12:00 PM

Quote:

Originally Posted by 03rubi (Post 369525)
Do you have a check engine light on? I would think that a code should be set in the ECM (computer) if it is running so poorly. However, sometimes it won't turn the light on even if a problem has been detected, it's called a soft code. Simply turn the ignition switch on, off, on, off, on and you should get the codes either as a flashing light or as a number on the odometer. That would be the first place I would go before I started throwing parts at the problem.



no codes at all. it "runs" fine..cranks right up, no missing or rough idle. It's just when you put it in gear, it has no power.

MOz 05-13-2009 12:26 PM

Anything stuck in the tailpipe? Did you fill up lately?

rrich 05-13-2009 02:29 PM

Sometimes when a cat self destructs, the pieces get caught in the muffler, plugging it. Or even can get caught in the pipe's bends.

I'm surprised nobody told you the easy test for a plugged exhaust.

No need for cutting anything -
Put a vacuum gauge on manifold vacuum, rev it up, it should still hold at least 15 inches of vacuum at 3000 RPM. If it's significantly lower, plugged exhaust. As you hold it at high speed, it will either stay low, or jump up, then slowly sink. A good exhaust system won't drop.

If it's only partially plugged, drive it while watching the gauge - make it falter - if that's it, vacuum will drop significantly.
Go to an independent muffler shop (not a chain), they can do the same test for almost nothing.
If it can't breathe out, it can't breathe in - no room. (Just like you lose your appetite when you are constipated - no room.)

Fuel test too - plugged filter, line, etc. Put a fuel pressure gauge on the rail at the engine - rev it to 3000 - it should hold that pressure without dropping if it's not plugged.

Do it the easy and logical way rather than throwing parts, time, and money at it.

'05 - you have the DIS ignition. The coil rail could be the culprit too. The internal insulation breaks down, limiting the spark. Listen closely - if you hear any "snapping" of the spark it's history.
And - Use a laser pistol type thermometer (harbor freight, about $30) from underneath. Both precats should be running about 350 degrees at their outlets. If one's is way too hot, like 700 degrees, and the other is too low, like 250, try another coil rail ($130 at a parts house, $230 at the dealer.)
I've seen several failures like that recently, identified with the thermometer, verified by replacing with a test spare.

I wish MSD would make a good coil rail replacement, they don't seem to be interested, too limited a market base.

cherokee980 05-14-2009 12:27 PM

Quote:

Originally Posted by rrich (Post 371758)
Sometimes when a cat self destructs, the pieces get caught in the muffler, plugging it. Or even can get caught in the pipe's bends.

I'm surprised nobody told you the easy test for a plugged exhaust.

No need for cutting anything -
Put a vacuum gauge on manifold vacuum, rev it up, it should still hold at least 15 inches of vacuum at 3000 RPM. If it's significantly lower, plugged exhaust. As you hold it at high speed, it will either stay low, or jump up, then slowly sink. A good exhaust system won't drop.

If it's only partially plugged, drive it while watching the gauge - make it falter - if that's it, vacuum will drop significantly.
Go to an independent muffler shop (not a chain), they can do the same test for almost nothing.
If it can't breathe out, it can't breathe in - no room. (Just like you lose your appetite when you are constipated - no room.)

Fuel test too - plugged filter, line, etc. Put a fuel pressure gauge on the rail at the engine - rev it to 3000 - it should hold that pressure without dropping if it's not plugged.

Do it the easy and logical way rather than throwing parts, time, and money at it.

'05 - you have the DIS ignition. The coil rail could be the culprit too. The internal insulation breaks down, limiting the spark. Listen closely - if you hear any "snapping" of the spark it's history.
And - Use a laser pistol type thermometer (harbor freight, about $30) from underneath. Both precats should be running about 350 degrees at their outlets. If one's is way too hot, like 700 degrees, and the other is too low, like 250, try another coil rail ($130 at a parts house, $230 at the dealer.)
I've seen several failures like that recently, identified with the thermometer, verified by replacing with a test spare.

I wish MSD would make a good coil rail replacement, they don't seem to be interested, too limited a market base.



thanks for all the info brother!! I will try some of these out and let you know what I come up with!!

cherokee980 05-17-2009 11:18 AM

Well I took an IR Temp sensor and checked the precats. They were both right at 675-685 deg each. The muffler itself was about 300 deg. So I have ruled out the coil pack. I disconnected the muffler completely and took it for a drive (good lawd it was loud), and same results occoured. I am confused bad here. All that is left is the fuel pressure check before I pull the transmission. Do any of you know where to check the fuel pressure? There is no fuel pressure port on the fuel rail...nothing at all. I have searched and searched with no luck at all of finding it!!! HELP!!!!!!!!!!!


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