Begster
NAXJA Forum User
- Location
- Cape Cod/Boston, Mass
I have a '91 Briarwood, 4.0 with AW4, factory transmission cooler. Bone stock, only upgrade is '95 vacuum booster.
I bought the Jeep 2 years ago with 65K on it, 1 owner, dealer maintained its entire life with receipts to highlight work done to it. Since I've had it it has been in a fender bender, and has been overheated since I blew a radiator hose off due to a loose clamp. It currently has 75K on it.
Problems:
Items replaced/checked:
Heat: At times it comes out barely warm at all, other times a little better. I'm used to my '99 and father's '01 where you can't hold your hand in front of the vent for an extended period of time, and can cook up a sweat if you leave the heat on for a while. I'm still shivering if I have the heat blasting on hi many times.
I've always driven it nicely, but 1 day last week I was trying to diagnose some issues, and ended up doing some brake stands and drove it really hard. Heat was noticeably hotter after this, confirmed by another Jeep friend.
Temperature:The Jeep has almost always ran hot since before the overheat. It runs at 210+ on roads/highway, and when crawling around the city the temperatures gets up there (approx 220-240). My e-fan has never come on due to temperature, but has been verified to work by the AC circuit and unplugging CTS. When it started getting colder, I was amazed that it would take so long to get up to temp, as the past 2 winters it has not failed to run hot. I will drive, it won't want to get up to 210ish, will rise when I'm stopped at a light, but will noticeably dip a good amount when I start moving again. I've smelled coolant many times after shutting the vehicle off and walking in front of grill, but it has never lost fluid and there are no leaks. Just a hot coolant smell.
Does anyone have any ideas on what I could be experiencing? I know the heater core is not clogged, it flows freely, but I'm can't definitely say that it is good or not. I would hate to go through the hassle of changing it and losing the charge on the AC system just to replace parts.
I've run a number of tanks of gas, always filling up from the same gas station, and have been recording the mileage. 12 when ever I'm doing city driving (which is how I get to work), and 15 when on the highway. The transmission "power/comfort" button does not make a difference. Have run injector cleaner through before and seafoamed.
I just don't know with the temperature issue anymore now that it switch from running hot to not warming up.
Any help/suggestions/questions are appreciated.
I bought the Jeep 2 years ago with 65K on it, 1 owner, dealer maintained its entire life with receipts to highlight work done to it. Since I've had it it has been in a fender bender, and has been overheated since I blew a radiator hose off due to a loose clamp. It currently has 75K on it.
Problems:
- My heat is lukewarm, but also inconsistent.
- My Jeep takes a lot longer to get up to temperature than it used to, and seems to fluctuate temp.
- Doesn't idle the smoothest, its not shaking all over the place, but there is a vibration at idle, and I can notice a harmonic vibration when stopped in gear.
- I can't get better than 12mpg and that is driving like an old lady
Items replaced/checked:
- Complete tune up when bough it
- Plugs (Champions)
- Wires
- Distributor cap
- Distributor rotor
- Air filter
- Replaced CCV tubes after finding oil covering original air filter
- Almost entire cooling system: When I drained the system the coolant was bright green and clean from the dealer
Napa water pump less than 2 years old- Hoses done and heater valve bypassed at same time
- Stant superstat in the entire time this has been going on, just replaced again with superstat 2 weeks ago, symptoms persisted
- New thermostat housing at time of water pump
- CSF 3 row 1 year old
- ZJ fan clutch 6 months old
- Heater core not clogged, flushes clear every time with no blockage
- Coolant temp sensor repaced 6 months ago from Autozone, fan still does not turn on though
- New 16psi cap
- Compression test performed roughly 10 months ago after overheat. No oil in coolant, no coolant in oil. I have not noticed drop in coolant levels
List from Cylinders (round numbers, don't have actual in front of me at moment)
130psi- 130psi
- 150psi
- 150psi
- 150psi
- 150psi
- Throttle body removed and sensors cleaned with sensor safe spray.
- TPS tested fine according to FSM test procedures.
- All new exhaust: Walker replacement exhaust pieces
Exhaust header not factory, replaced by dealer. Is the header with belows on it, haven't seen any cracks.- Muffler and tail pipe replaced 1.5 years ago
- Down pipe and Cat replaced 2 months ago.
- Bosch o2 sensor
- Harmonic balancer, idler bearing and belt changed 1.5 years ago
- Dealer converted to R134a AC system.
Heat: At times it comes out barely warm at all, other times a little better. I'm used to my '99 and father's '01 where you can't hold your hand in front of the vent for an extended period of time, and can cook up a sweat if you leave the heat on for a while. I'm still shivering if I have the heat blasting on hi many times.
I've always driven it nicely, but 1 day last week I was trying to diagnose some issues, and ended up doing some brake stands and drove it really hard. Heat was noticeably hotter after this, confirmed by another Jeep friend.
Temperature:The Jeep has almost always ran hot since before the overheat. It runs at 210+ on roads/highway, and when crawling around the city the temperatures gets up there (approx 220-240). My e-fan has never come on due to temperature, but has been verified to work by the AC circuit and unplugging CTS. When it started getting colder, I was amazed that it would take so long to get up to temp, as the past 2 winters it has not failed to run hot. I will drive, it won't want to get up to 210ish, will rise when I'm stopped at a light, but will noticeably dip a good amount when I start moving again. I've smelled coolant many times after shutting the vehicle off and walking in front of grill, but it has never lost fluid and there are no leaks. Just a hot coolant smell.
Does anyone have any ideas on what I could be experiencing? I know the heater core is not clogged, it flows freely, but I'm can't definitely say that it is good or not. I would hate to go through the hassle of changing it and losing the charge on the AC system just to replace parts.
I've run a number of tanks of gas, always filling up from the same gas station, and have been recording the mileage. 12 when ever I'm doing city driving (which is how I get to work), and 15 when on the highway. The transmission "power/comfort" button does not make a difference. Have run injector cleaner through before and seafoamed.
I just don't know with the temperature issue anymore now that it switch from running hot to not warming up.
Any help/suggestions/questions are appreciated.
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