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Unread 11-13-2011, 03:25 PM   #16
oldtime_ironman
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Quote:
Originally Posted by 87milton View Post
will do, also what is the exact name of the temperature sensor? is it called the coolant temprature sensor?
I believe so. On my 91, there's 2 of them - one in the thermostat housing, one in the way backside of the head, on the drivers side. Forgot which one does the computer and which one does the gauge tho

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Unread 11-14-2011, 03:08 AM   #17
dodger889
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The one on thermostat housing is the computer. The one driverside rear is for the gauge.
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Unread 11-14-2011, 08:21 AM   #18
87milton
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yeah on mine i know the one on the head is the sending unit for the temp gauge. and i belive i found my coolant temp. sensor on the intake manifold? my jeep is an 87 2.5 TBI
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Unread 11-14-2011, 11:55 AM   #19
Lee_N
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A few thoughts - 1) Gutted cat has lowered the back pressure, thus the O2 sensor may not be reading correctly. 2) Check the fuel pressure to see if the regulator is working right. Who "rebuilt" the throttle body? I would assume if it was rebuilt, they would have replaced the TPS, the pressure regulator, and the injector. Along this same thought, check the TPS to make sure it's reading right. Should read between 4.6-4.7V. 3) Check the Wide Open Throttle switch. This richens the mixture at WOT. 4) Check the MAT. 5) Make sure the injector isn't leaking. I would assume this also would lead to flooding when starting, so probably not a problem.

You can also search google for Jeep Wrangler D1 diagnostic to find some info from the FSM. Look for a URL that ends in .fr. Should be the first hit.
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Unread 11-15-2011, 08:48 AM   #20
87milton
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this sketchy mechanic my moms boyfriend knows but i think all he did was replace the seals in it. i know a gutted cat dont help anything but i also just found 2 exhausts leaks. first there are two small holes on the manifold right where the o2 sensor is just on the other side of the pipe. i think this might just be it. the second one is where the pipe joins to the cat converter. i hear muffler putty calling my name haha
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Unread 11-15-2011, 09:04 AM   #21
oldtime_ironman
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Originally Posted by 87milton View Post
this sketchy mechanic my moms boyfriend knows but i think all he did was replace the seals in it. i know a gutted cat dont help anything but i also just found 2 exhausts leaks. first there are two small holes on the manifold right where the o2 sensor is just on the other side of the pipe. i think this might just be it. the second one is where the pipe joins to the cat converter. i hear muffler putty calling my name haha
Bingo, you found it. If possible, I would get it welded up for a permanent fix. Never had much luck with muffler mud, myself - it always falls off after a bit.
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Unread 11-16-2011, 08:09 AM   #22
87milton
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yeah thats what i want to do. i got a welder and tried it myself and failed haha. mostly because i didnt take anything apart or clean the metal haha. after christmas i think ill get someone who knows what there doing to give it a go. also i was supposed to have run out of gas like 10 miles ago so hopefully this putty stuff is working =]
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Unread 11-16-2011, 04:38 PM   #23
oldtime_ironman
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Originally Posted by 87milton View Post
yeah thats what i want to do. i got a welder and tried it myself and failed haha. mostly because i didnt take anything apart or clean the metal haha. after christmas i think ill get someone who knows what there doing to give it a go. also i was supposed to have run out of gas like 10 miles ago so hopefully this putty stuff is working =]
Or ya could just get a whole new down-pipe and cat, that way its a bolt-in job. Any more black smoke yet?
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Unread 11-16-2011, 08:59 PM   #24
bharris68
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Your exhaust manifold is likely broken, most of them are - if it's LOUD under the hood, that will be part of the problem, too.
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Unread 11-29-2011, 11:03 AM   #25
87milton
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still black smoke and still bad mileage and its not really too loud under the hood, the putty has held up but no improvment in anything
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Unread 11-29-2011, 12:04 PM   #26
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Black smoke tends to indicate running rich... Check to make sure your injector isn't leaking?

What other sensors have you replaced? Are you sure it has the correct computer?
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Unread 11-29-2011, 10:01 PM   #27
87milton
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changed 02 sensor map sensor and egr valve. the fuel injector is less the 6 months old and as far as i know the computer wasnt touched. i changed the ignition coil and now i get 8 mpg haha
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