The Frog Blog

[rocknxj]

Drove the 35 mile commute to work today and I still have a slight sucking sound at the intake manifold when I stomp on the gas. Not as bad as before, but definately there. I believe I will remove my driver's side engine mount for better access to the lower manifold bolts. I need to swap out my poly bushing anyway, and I think I'll finally have full access to the bolts with the mount out of the way. I wonder what the breaking point is for those bolts??? That would suck if I broke a bolt in the block.

I also noticed on my early morning drive that I lost my cruise control. First my airbag light came on steady, then I lost my horn. Now I lost my cruise control. Next will be my guages. I really need to reseat my connector behind my instrument panel.

This has been an unnecessary Tuesday lunchtime Frog Blog update. Please return to your regular activities.

 

[frontman]

This has been an unnecessary Tuesday lunchtime Frog Blog update. Please return to your regular activities.

LOL

 

[rocknxj]

A "nooner" would have been preferred.

 

[american_zero]

I wonder what the breaking point is for those bolts??? That would suck if I broke a bolt in the block.

On my last XJ I was snugging down the rear most header bolt and broke it! It didn't take much and if you re-used the old hardware be very careful with it. I ended up never fixing that bolt and just tried to ignore the major exhaust leak when cold. The head would have to come off to get at the last one or two bolts with an extractor of any kind. :tears:

Since your cruise control doesn't work I would trouble shoot that first as it may lead you to the source of your vacuum leak. Maybe the hard plastic vacuum line going to the canister broke?

 

[rocknxj]

On my last XJ I was snugging down the rear most header bolt and broke it! It didn't take much and if you re-used the old hardware be very careful with it. I ended up never fixing that bolt and just tried to ignore the major exhaust leak when cold. The head would have to come off to get at the last one or two bolts with an extractor of any kind. :tears:

Since your cruise control doesn't work I would trouble shoot that first as it may lead you to the source of your vacuum leak. Maybe the hard plastic vacuum line going to the canister broke?

Those are very good points and I appreciate your post. I'm a little timid when it comes to exceeding torque values, especially with those pesky hard to reach areas. I might swap those bolts one for one in the near future. If nothing else, once I pull the engine mount, I will loosen everything, reseat the intake manifold, and retorque the bolts in proper sequence and value. Damn that would suck if I broke a bolt. I'd poop myself for sure.

The cruise control used to work (days ago) but now I have no power to it. I'm thinking it has to do with an electrical connection at the connector behind the dash since I get no CC on light. If it was a vacuum leak, I would get power, but it would not hold...er so I think.

 

[rocknxj]

First, before I post yet again on the FB, I have to admit that I am a blogowhore and I have no way of controlling how much I post on my blog, or that of my fellow NAXJers. I am a blogoho. Now, on with another update...

Tonight I had just a few minutes to work on the Jeep so I decided to climb underneath and take a few photos of my flex pipe for those of you contemplating this companion to the APN header.

Not satisfied with just the flex pipe photo, I decided to remove my inspection plate on my transmission. smart guys said my fly wheel bolts were loose, causing the odd rattle sounds at idle. What I found surprised me.

All four flex plate bolts were so loose I could turn them with my fingers. The photos below are not very good, but you can see the space beneath the bolt head. Scary thought, that. Not sure what would happen if the flex plate actually came loose, spinning away from the engine and chewing a path of destruction with it's jagged metal teeth of death...

The torque value on the flywheel bolts for my model year is 105 ft lbs. With oil pan installed, it is difficult to prevent the fly wheel from turning while torquing to that level. I had my kid (100K XJ) turn the crank shaft from the front of the motor so I could get to all of the bolts. I also found a 15mm crow's foot to be the best device for torquing them babies down. Anyway, I re-installed the inspection plate with it's ludicrously large bolts, reattached the coil wire, and cranked up the engine. I am happy to report NO RATTLE sound. The Frog is a clean running (albeit slightly wheezy from sustained intake manifold vacuum leak) off-road machine.

For a parting shot, here is a photo of the Magnaflow muffler.

Tomorrow is gym night, so there will be no XJ fun for me on Wednesday. Maybe I'll take my Jeep to the mall.

 

[trailmaster6536]

Great photos and methods for the fix. But the condition still miffs me. Was there previous work done on the transmission that would have necessitated removal of the bolts to begin with? It is just a really odd thing to have to tighten along the way. Those just are not things you need having a mind of their own.

 

[rocknxj]

Great photos and methods for the fix. But the condition still miffs me. Was there previous work done on the transmission that would have necessitated removal of the bolts to begin with? It is just a really odd thing to have to tighten along the way. Those just are not things you need having a mind of their own.

I have a pretty detailed log book of everything that was done to the Jeep by the PO before I bought it, and there is no mention of tranny work. It was making that sound when I bought it from him and I figured it was a loose heat shield, because that was almost exactly how it sounded. He did a great job at keeping up with mx and using quality parts and fluids, so I am thinking it is just one of those odd things. There is no evidence of repair or maintenance, either. Very strange.

 

[fyrfytr1717]

Wow, that's the shortest pice of flex I've seen... So is it really necessary to keep that bubble (I believe it may be called the "resonator") in your exhaust system. Does it provide some sort of performance benefit, or was it just left there because you weren't replacing the rest of the exhaust pipe?

 

[rocknxj]

Wow, that's the shortest pice of flex I've seen... So is it really necessary to keep that bubble (I believe it may be called the "resonator") in your exhaust system. Does it provide some sort of performance benefit, or was it just left there because you weren't replacing the rest of the exhaust pipe?

That's a cat converter and must be retained in the system, unfortunately.

 

[VET'S XJ]

Glad it was just the bolts like we thought at Deer Valley! Mine were loose at one point too...such an annoying rattle! Flex pipe looks good too...

Bryan

 

[rocknxj]

Glad it was just the bolts like we thought at Deer Valley! Mine were loose at one point too...such an annoying rattle! Flex pipe looks good too...

Bryan

Yeah Bryan, that was a brilliant call and I owe you big time. I have also learned that the so called flywheel is really a flex plate on an AT sytem. (My maint book calls it a flywheel, though).

One thing I am pleased about with the flex pipe is the elimination of the stock downpipe flange. The stock flange sits right at the tranny inspection plate, which makes removing the driver's side bolt impossible. Now that I don't have that flange, my inspection plate comes off in a matter of seconds. If I ever need to retorque my flex plate bolts, I can do it in under 5 minutes.

 

[american_zero]

If they give you any more trouble, I would consider pulling the bolts one at a time and reinstalling with some Loctite on them.

How would you describe the tone of the Magnaflow against say the Dynomax catback or a Flowmaster? Hows the interior noise? Quiet while cruising?

 

[rocknxj]

The Mag is definately quiet during cruise, but you get a satisfying growl during start and acceleration. I used the same muffler on Old Blue and I loved the sound on that Jeep. Truthfully, I was hoping for a bit more deep rumble with this Jeep considering I also have the APN, but it sounds about the same as with a stock exhaust manifold. Once I am finished with my intake leak, I may indeed get more of that satisfying exhaust tone.

From what I've heard, the Magnaflow offers a nice compromise between stock and a Flowmaster. That, of course, depends wholly on your age. I'm a fan of the Magnaflow decibel level.

 

[fyrfytr1717]

That's a cat converter and must be retained in the system, unfortunately.

You sure about that? So far as I know, the 99's (even the CA ones) only have one cat, the big one back by the transfer case. The FSM for the '99 also only mentions one cat. That bulge is shown in the FSM diagram of the exhaust system, but no mention is made of it having any function.

 

[trailmaster6536]

Both my 2000 and 2001 have sets of precats right after the header and then from the precat flange over to the primary cat it is a smooth bend that sweeps across in front of the trans pan. Have had no cracking issues with the headers on either, although the precats died on the 01 two years ago and threw codes like it was party. waited 6 weeks for one to get built and put it on and everything was all good. Not to mention the absence of some wierd exahust smells.

 

[rocknxj]

My exhaust pros claimed the bubble was indeed a cat and even inspected the inside for wear/damage. All looked good and they welded the flex pipe to it.

I just checked my Haynes manual and it does not show that as part of the exhaust on my '99. However, that same manual has already gotten me in trouble this week with the whole flexplate/driveplate torque debacle. I may buy a FSM yet...

 

[XJensen]

I know there were quite a few changes in 2000. The drive train was even shifted over a couple of inches to make room for the added emissions stuff.

Josh

 

[trailmaster6536]

Josh is right, they did do a bucnch of things some good and some not so good. They may have experimented on the 99 before going to the dual precats.

2000 Exhaust Sweep

2001 Exhaust Sweep

Little Precat Devils

 

[srmitchell]

They are all different.

Tim's (knucklehead61) has the same exact exhaust I do, but his has no precats. (same header and down tube, but its just straight pipe where mine has mini cats. ) He has a 2000, mine is an 01.

Its seems to be sorta random.