My 1989 FJ62 4.0 straight 6 runs rough and smells rich until it warms up. After that it runs great. Any ideas/suggestions?
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It's a new vechicle to me. It's done it since I got it. I'll try a coolant temp sensorIs this how it has always run or did it just start happening? How are your air and fuel filters? Plugs, cap, rotor, wires, battery cables and connections? Have you checked for vacuum leaks? Does your state smog test?
assuming the above is ok then you might have a bad coolant temp sensor.
It's a new vechicle to me. It's done it since I got it. I'll try a coolant temp sensor
cleaned the grounds when I changed all the belts and hoses. I have a FSM. I'll check it. ThanksBefore you go throwing parts at it you can measure the resistance across the sensor when its cold and when its warming up. Other problems could be bad grounds or low battery charging. If the voltage is low it can send all the efi sensors out of wack. Do you have the Factory Service Manual (FSM)
Filter was clogged! Washed and dried. No difference. I did find a wire, no connector, that was folded and tucked under the he thermostat housing. I didn't find anything that it looked like it had a a wire missing.Before you go throwing parts at it you can measure the resistance across the sensor when its cold and when its warming up. Other problems could be bad grounds or low battery charging. If the voltage is low it can send all the efi sensors out of wack. Do you have the Factory Service Manual (FSM)
No check engine light when key is on, no jumper in diagnostic port. I'll pull the dash cluster and check the bulb tomorrow,It's a new vechicle to me. It's done it since I got it. I'll try a coolant temp sensor
Disconnected the coolant temperature and it started, ran at high idle(1,200rpm) smooth. I shut it off, reconnected the sensor and it ran rough. Maybe Ill disconnected it until the sensor comes in.Before you go throwing parts at it you can measure the resistance across the sensor when its cold and when its warming up. Other problems could be bad grounds or low battery charging. If the voltage is low it can send all the efi sensors out of wack. Do you have the Factory Service Manual (FSM)
I replaced/
cleaned the grounds when I changed all the belts and hoses. I have a FSM. I'll check it. Thanks
Did all of that before I posted.check for a vacuum leak
I did. Checked all the hoses where tight and not cracked. Sprayed carb cleaner all around the engine in hopes of finding a leak, no change in RPM. Changed cap and rotor, has new plugs. Runs much better when warmed up for 10 minutes.check for a vacuum leak
It's rich even when warmed up.My 1989 FJ62 4.0 straight 6 runs rough and smells rich until it warms up. After that it runs great. Any ideas/suggestions?
Replaced the check engine light. It comes on with the key on but goes out when the engine is running.No check engine light when key is on, no jumper in diagnostic port. I'll pull the dash cluster and check the bulb tomorrow,
Replaced the check engine light. It comes on with the key on but goes out when the engine is running.
The vechicle is running rich all the time. I'm cleaning the throttle body and replacing a cracked air intake hose.Before you go throwing parts at it you can measure the resistance across the sensor when its cold and when its warming up. Other problems could be bad grounds or low battery charging. If the voltage is low it can send all the efi sensors out of wack. Do you have the Factory Service Manual (FSM)
I've got one coming.So it passes its internal checks at least. Also probably indicates that no sensor has truly failed. As a back seat driver I feel this is related to the coolant temp sensor...which is either sluggish or not reading properly.
I need to look at the 3FE manual but usually you can measure the resistance across the sensor while heating it up in a pot of water on your stove and you should see the resistance change. If you have a fancy DVOM with graphing capability you can plot the resistance over time and inspect the curve for issues.
and even more simply measure the resistance across the sensor when engine is cold and measure it again when its hot and see if it aligns with the FSM
I could smell it, used 1/4 tank in 20 milesBTW how do you know its rich all the time?