Jonreif

I have a 91 XJ 4.0 i6 and around town its fine runs 190-220 range and seems fine never been a ton of power on takeoff but you know its been derivable.

I went out for a longer trip today and at 50 before interstate it started heating a little hot maybe 230 (its 100 today so i thought meh) went to interstate and noticed i could not get up to speed, could not get up to 65 even! I was watching heat climb... when the needle hit the last white mark I flipped from AC to defrost heater and opened windows slowed to 50ish and got it below last mark.. i pulled off 1/4 mile ahead let cool to 210 and carried on a mile with windows opened..and kept below 210 but still had no damn power... seemed to somewhat come back to power with cooler engine but came home and parked cutting trip short. still seemed dogish hot. at no time did i allow it to red but it still had no power for a bit to even climb a small hill... as it cooled i got up to 40 rest way home and ran cool took off from stops easy going.. i only allowed it to touch near the red zone as seeing that last white temp bar was enough for me.

i do know the cat rattles a bit and well shes got age... 176k on body supposedly 75ish on motor but cant verify this 100% first hand as only recently had it and got it going with fuel pump and such... is it possible blocked cat? or is this sounding like cracked head? or head gasket? ***gulp*** shudders a bit in fear.....

im thinking tomorrow morning I may do a compression test as i have not done one and this jeep and **should** rule out cracked head or head gasket just wanted her cooler before the compression test as it was warmed up and heck its still in 90's out there now.. what should these I6 come out at for compression? I don't have a book on them for spec.

also i believe various electronic i stuff can cause some of this as well but that's out my league..

anyway like i say the cat is rattling particularly on shutdown it rattles at ton and pounding on it makes really strange sounds... Yes, im planning on getting that done just putting it off as i hate to take things to shops and really the cat welding is a shop item (so if that's it would be fine) but idea of cracked head or head gasket makes me tremble the every fiber of my being..

hopefully I have all the information here in detail enough. any other things i should be considering or looking at? if it was just the heat id say rad or fan but the power thing is what sticks with me...

thanks much for your time here.. regards, j reif

GreaseMonkey17

A lot of times when a cat is rattling it has dislodged itself from the converter body and it will allow the loose piece to turn where the honeycombs face the body instead of allowing air flow through totally cutting off most if not all exhaust which can cause you to overheat and certainly a major lack of power ... loosen up your exhaust before the cat purposely causing a exhaust leak and see if your lack of power etc is solved .

Jonreif

That's a good idea.. did not think of that.. probably have to be off the ehaust manifold but yeah...

GreaseMonkey17

Let me know I'm curious to see what you find .

Jonreif

yeah, ill keep ya updated.. ill try a compression test in Am and see what that gives me.. if that comes up good ill give i a whirl as after all going to have to have the exhaust done anyway...

GreaseMonkey17

I would try the exhaust first just because I really think that could be the issue and am curious to see if I'm right haha

freegdr

If cats rattling substrate is broken. Its like trying to run with potato in your mouth plugging breathing. And gonna get hottter temps.

Jonreif

Yeah I'm figuring my cat looks like the pic. I guess we're gonna do the exhaust this weekend but first I'm going to run a compression test on the motor and verify head and head gasket are in good shape and that's not my power issue.

Jonreif

Tomorrow my cat and pipes come. I'll be panting like a puppy for the fed ex truck. Lol. I'll let Everyone know if that's the issue. I also have what appears to be power steering leak I just damn well cannot find. Errrrr.

Jonreif

See its spraying here! Appears to be power steering. I have air box off and still cannot see it spray ever. I have done more pictures than a photographer of the area and can't spot the damn leak. Anyone have an idea where this devil is spraying from. Looks dry everywhere except here and below here where it runs down. Frustrating as hell I can't just see it.

Jonreif

I've wrapped shop towel around hoses and as much around back of ps pump as I can yet no wet towels. I'm really beside myself location it's sourced from.

Basslicks

You sure it's not gas? I had the supply line going to the rail get a pin hole leak on me and start spraying in that area a few months back.

Jonreif

Yes it's definitely power steering fluid. And im dropping level in the ps pump fast. When I crank the wheel I get a mist and smoke off the manifold there if it gets hot. I'm trying not to run it to hot as I know ps fluid is likely to catch fire on the exhaust manifold of hot. I recently did fuel lines clean as well and I got pressure holding on my system great now. I notice some spray on ground even yet when I look from under all I see is a mist and can't pinpoint where. Tomorrow a friend is coming and I'll be able to dig into it deeper before we get the exhaust done. I'm still suspecting a ps hose I just can't find its leak to confirm so hate to start randomly buying and replacing. Might just buy the hoses then see and move to a pump if we can't pinpoint this silly leak.

Basslicks

If it's doing it when you turn the wheel, the only hose it could be is the pressure hose. The return hose won't do that when you turn the wheel. The pressure hose could be in good condition itself, but the threads may be messed up. So check and make sure the fittings are tight on each end. The hose shouldn't cost more than about 30 bucks.

Jonreif

Yeah that's why I was wrapping it in shop towel even. I'm confused why it's not showing I'm sure tomorrow I'll spot it. Was thinking I'd go for a new hose this one looks suspect.