The variation in the long term fuel trims are interesting… high readings occur when I’m driving around.
Intermittent blinking engine light only when idling (no codes)
- Thread starter MikeE024
- Start date
The variation in the long term fuel trims are interesting… high readings occur when I’m driving around.
timely thread. My "Check Gauges" light came on today, my temperature gauge was just touching the red while sitting in a drive thru line. it did come down after moving again. I checked everywhere around and under the engine and radiator area and I find no leaks or moisture anywhere?
Why would the engine overheat for no apparent reason. Oil pressure was fine/normal? ambient temp was 78°
The readings are taken from the Banks programmer (old Diablo unit).
Today was the first time that I looked at the closed loop AFR. I don’t recall seeing that AFR number move. I’m not sure what that number represents or how accurate it is.
Was your radiator fan running properly?
Could be a fan clutch and/or a stuck thermostat.
I purchased a rig with a failing electric fan and a 205* thermostat (when it should have been a 195*). I overheated at the emissions station and my coolant boiled over.
Make sure your coolant is correct, in good condition, and the levels are good.
STFT is real time data, but if the LT values are off due to running with leaks that are now corrected, you’ll need to clear the data from the pcm.
Either your thermostat temporarily stuck shut or the fan clutch is going bad. I'd kinda lean toward the ran clutch since your temperature came back down once you started moving again. Hayden is a good brand of fan clutch if you can't find a Mopar. If it turns out to be a bad thermostat, which sits in the cooling system, go strictly for a 195 degree non-failsafe thermostat. I say NON-failsafe because while failsafe thermostats sound good and they usually won't fail in the more dangerous closed position, they fail entirely too often in the open position which not good either. A Mopar 195 degree thermostat would be a great choice.
should there be any wiggle to the fan? I did think it maybe the water pump, but then there should have been some leakage. I wiggled the fan blade and it does move slightly???
oh ya, ever since I got the Tj, the gauge reads just under 210°. Now im thinking its the wrong thermostat
should I replace the entire assy?? plus the T'stat, the TJ has 97K miles on it. I can only guess they are original
Reading just under 210* on the temp gauge is very normal since the thermostat doesn’t open until 195*. But overheating when you stop is not normal and should be fixed asap.
That causes me to lean more at you having a fan clutch issue, but if it were me, I’d also install a mopar 195* and know u are good.
For good measure, you can boil the thermostat to confirm it opens before you install it.
Additional note: If your system is corroded, I’d look at replacing the hoses, radiator (mopar), and water pump (mopar). Drain and flush the system from the block to get the gunk out before you install the new radiator.
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I’d do the clutch and thermostat for sure.
Then decide if you should do the other parts as well. I replaced everything except the heater core because my system overheated and was also badly corroded.
My dash gauge reads just below the needle and my scanner showed it was 196-198* even with the turbo.
its only overheated one time, yesterday? it has never done that before??? and when, on the way home, it did not overheat when stopped at a traffic light, even with the a/c running??? and Az has some L O N G traffic lights, LOL
The cheap one that I liked for live data was stolen and is no longer available.
I was using the Banks programmer that came with the turbo yesterday.
I ordered three more cheap scanners since the cheap one that arrived last night didn’t show much live data info. I’ll let you know if any of these cheap scanners are worth keeping. Let me see if my old device is on eBay since I only checked on Amazon.
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I still get this, I think it's one of the reasons Banks killed their Turbo for the TJ's. I worked with them for quite a while and they were never able to resolve the cylinder 3 misfire.
That's a bummer.
I'm getting a solid engine light with a P0303 code more often today.
Do you have a copy of a 05/06 tune from Banks that I could try? (it could be newer than the tune I'm running)
It would likely be in the "tunes" folder within the main "Intune" folder.
The cheap scanner I got yesterday showed live data today, but I still don't like it because it only shows in *Celsius rather than *Fahrenheit. The other cheap scanners didn't arrive today so I'll probably get them tomorrow. I'll be in touch.
Side note: The old scanner I used doesn't have a part number showing in Amazon bc the listing now represents a far more expensive ($200) touchscreen scanner that I'm not interested in.
Gotta keep it short. I’m keeping this one.
https://www.amazon.com/gp/aw/d/B0894G8C6L?psc=1&ref=ppx_pop_mob_b_asin_title
Gives me the live data I wanted and quickly clears codes. The settings allows you to choose f* for units.
I wonder if running cooler plugs or running an intercooler would help with this issue.
Fwiw, I added more heat wrap around cylinder 3 and clocked it to the 2 position. And I replaced my other three NTK o2 sensors today to have a clean slate on this items.