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What a piece of leaky.....

xjblue

NAXJA Member #496
NAXJA Member
Location
Utah
Junk!

My friend has a 90 XJ, 4.0 aw4. She has been complaining of tranny problems and leaks for some time. It overheated today so I went and helped her out. It's leaking coolant from well I'm not sure but it was dripping off of the serpentine belt underneath the lower big pully among other places. Then there is a line that comes foreward from the bottom, passenger side of the engine that changes to hose as it bends up and towards the drivers side in front then changes back to steel and disappears above the steering knuckle, it was leaking a steady drip of dirty acrid fluid (ATF?) Bubbling out at the connection where it changes from a metal line to hose. and the first big problem I noticed (yeah besides all the dripping) was that as soon as the engine warmed up it began to increase it's idle speed gradually at first but then revving up to freeway sounding speed and kept sounding faster and faster. This explained to me why the tranny has been giving out and must be contributing to her overheating. She explains to me then that it will rev up on her like that unless she uses premium gasoling or a specific fuel clensing additive. Any Ideas at all on what to do first with this "increasing Idle" buisness would be helpful. Thank You.
 
Increaseing Idle could be the TPS. I had a Ford go bad and it was like I was reveign the engien but did not have a foot on the pedal. As for the leaks. Replace all the hoses and it sounds like you are talking about the weep hole on the water pump. If that is leaking its Water pump time.
 
First of all......

Remember that XJ is 13 years old. If has had a rough life and used in rough service as many are, aaaand poorly cared for will be a hadfull. Might not be worth fooling with at all.

The 'over active' engine speed from the sounds of that poor beat-up vehicle could be so many things. Probably one job i'd run from.....just too many things possible. Could be as simple as low coolant- you did say it had that leak. Just how hot did it get?? Damage from that too? If it is the trans slipping causing that RPM increase, then the trans is toast. Nothing easy to do with that for sure. Lots of things at play here.

Hope she is a goooood friend cause sounds like a handfull. Many XJ's out there of that vintage in waaaay better shape for really quite low prices.
 
Sounds like a bad TPS and a leaky water pump.

The high idle is a frequent problem on the non-HO engines. Step one is to remove the connector and clean all the terminals very well, then plug it in again and see if that helps. It's rare to actually need a new TPS -- usually just needs to have the terminals cleaned and maybe an adjustment.
 
MY 89 has recently started the overrevving also. and i have yet 2 find a solution.My tranny is n great shape tho, so i dont think there is a relation there.And no water leaks.If that helps u, not sure. but u might no what it is NOT.I am pretty sure there is a sensor somewhere not within norms. dangit.Actually i have a knocking rod, ugh. so mine isabout 2 b down 4 the count as well.good luck with that revving prob, if u find the solution lemme no.oh yeah, how many miles does it have on it? mines at 189,000
 
Eagle said:
Sounds like a bad TPS and a leaky water pump.

The high idle is a frequent problem on the non-HO engines. Step one is to remove the connector and clean all the terminals very well, then plug it in again and see if that helps. It's rare to actually need a new TPS -- usually just needs to have the terminals cleaned and maybe an adjustment.

hmmmm well what a convienently timed post. thanx.. i will try that on mine riiight now
 
Thanks for all of the quick input! She has 240,000 miles on it, seen alot of hard Minnisota winters. When it overheated I don't think it got too bad because she pulled over as soon as she noticed steam coming out. By the time I got to it, it was already cooled off and the coolant was definantly low, added some coolant, had her start it so I could see what was going on, then after the idle sped up I noticed it getting hot so I had her shut it down, added more coolant and had her drive it home (about a mile). I'm not familiar with the cooling system (resivoir neer firewall & no radiator cap) so I have no idea if we got enough coolant in there. Now I wish I had read all of those posts on the TPS, I'll clean it and see if I can keep her running for a little longer. I was thinking it was the water pump too. I'm thinking her tranny is shot on top of it all, I've advised her to keep an eye out for a new car but she can only afford another clunker at best.
 
FYI, i went out, undid the TPS, messed with it, cleaned the heck outta my Throttle Body( it wasnt that bad but u might as well if u have it opened up)left the TPS loose, started it,no more super-revving upon startup anymore!!!adjusted the TPSand tigthened it down.hope this helps u n your quest 4 answers:cool:
 
1 down, 2 to go

Did like Wallyman and messed with the TPS and cleaned things up though I felt like I didn't know what I was doing. Had her start it up, no high idle after warm up! Checked the tranny fluid level.... DOH! the dipstick was dry confirming my suspicion that tranny fluid is leaking. Added what fluid I had on hand, quart and a half, then took it for a test run, no problems with idle or tranny slipping after a little trip to the gas station to fill up some low tires for her. She said it ran much better, Now all I need to do for her is the water pump and stop the tranny fluid leak! The only noticable leak is from where I described on the first post that I suspected was ATF. I believe it is the return line from the tranny and it leaks where the metal line changes to hose and crosses in front of the engine. Can I just wrap it with something or replace the hose or do you have to get a whole new line?

p.s. the temp gage in the dash no worky! any ideas there also appreciated. Thanks
 
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Re: 1 down, 2 to go

xjblue said:
The only noticable leak is from where I described on the first post that I suspected was ATF. I believe it is the return line from the tranny and it leaks where the metal line changes to hose and crosses in front of the engine. Can I just wrap it with something or replace the hose or do you have to get a whole new line?

If one line is leaking, I'd say just bite the bullet and replace both lines - since they're probably both the originals, the second line is most likely not far from leaking. Personally, I wouldn't trust a "muffler bandage"-type patch on a pressurized line like that - it could still let go, or fail in another spot.

Rob
 
Change the water pump ($45 & 3 hours). Replace both supply and return tranny lines. These are a PITA ($80 and 5 hours). Convert to an open cooling system ($300 and 8 hours). Clean TPS and throttle body ($0 and 30 minutes).

Driving a 1990 XJ off of a cliff while emptying your .45 into the gas tank (priceless)...

Thanks you...
 
She probably has the plastic quick connects where the rubber hoses connect to the metal lines of the radiator. There are two plastic "ears" on the connector (they're hard to see) that you squeeze together to separate the connection. Mine was leaking a bit, and I just disconnected them and cleaned them up to get a solid connection. Now they're fine. You might try that first.
 
on my 89 the hoses are crimped. Since it was wrecked and the lines all bent I had to improvise.
First remove the air box. The front skid plate if so equiped as well so you can get in there to work on it easier. If you do it at the same time as the water pump go ahead and pull the radiator, that makes it even easier.

What I did is take a cutting wheel and carefully remove the steel crimp then take the hose off. This will leave the hose barb on the end of the steel line. I then replaced both hoses and put them on with good hose clamps. No problems so far after a year.

If you remove the steel hard lines most parts stores will have a crimper and can put a steel crimp back on instead of a hose clamp if you want.

Get this fixed soon as runining an automatic low on fluid will kill it pretty fast. Make shure she is checking the fluid level often (daily) until then.

When you do the water pump be shure to put a new upper and lower radiator hose on while you are at it.

Andy
 
update...

Out of all the great advise above.... Best was = Probably should have walked away from this job! The bullet to the gas tank Idea might be a waste of a good bullet. To top it all off I found out this rig had been used to carry the U.S. Mail to some rural locations.

Anyway, discovored a possibly very poorly connected lower radiator hose. Replaced said Hose and the water pump and due to time issues (time to go to Moab) just taped the leaky end of the tranny return line.

Fired her up and the High idle problem returned! followed by the other end of the tranny hose leaking and found two bad leaks in the coolant hose coming from the heater; a bad filler cap style T splice and a bad connection at the heater valve(?) where hoses connect in from the heater and the bottle. Uhhg!

Broke the plastic connection to the valve (double Uhhg!) so ended up replacing the whole thing with a regular T and a new cap T w/ new hose and clamps - no more coolant leaks! the line from the heater will always be open but I don't think this Junk will last till next summer anyway. taped up the other end of the tranny hose and stoped the flow of ATF to the pavement down to an acceptable for now one small drip per several minutes. Then I pulled the nasty clogged air filter for a clean new one and unplugged the obviously offending "blowby" hose connected to the airbox to keep the new filter clean, presto - no more high idle!

After all that work I still expect it to explode in a Simpsons style fireball at any moment! Thanks again for all the help!
 
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One other thing you may want to do since you're such a great guy helping this woman out...:) ....is to pull the IAS motor from the throttle body and clean it. The first time I cleaned it on my first XJ it helped smooth the idle and eliminated a slight over-rev issue I was having.

Tom
 
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