jr07871

99TL, 190K, I blew my upper radiator hose and left my key on to cool engine down. Ended up with a dead battery. Replaced the hose and jump started. Since that time, I have had a surging idle - constantly varies between 1200 and 1800 RPM in park or neutral. I think I initially had air in the cooling system although I believe I have gotten that all out (temp gauge used to climb while in drive at a stop light). Is there no cooling system bleeder valve? I believe I have worked out all the air as this no longer happens.
I have disconnected battery, cleaned throttle plate and reset ECU? (key on, gas pedal to floor 5 sec, key off, wait 2 min).
I am at loss as to what to do next. Seems to me the ECU needs to relearn the but is not happening. It has been a week now, disconnected battery, reset ECU several times, After a while of driving, the CEL comes on then eventually the TCS light also.
Help?

acutee

It is best to get the code reader and find out what the problem is and go from there.

jr07871

I think the CEL light is an result of running for a period of time with the engine idling so erratic. I think it is a symptom but not the cause, although I could be wrong. I will pull codes tomorrow during lunch and report back.
Thanks

01tl4tl

pull the CLOCK fuse on passenger end of dash
assuming 99 same as later years of gen2- thats the secret backup power to ecu
and forces a reset and relearn

a bad battery will cause some of your problems- get that tested since you ran it dead.
if the sensors dont get the correct voltage they make the car run funny

Running the cooling fan was a valient effort- but the heat in the engine was the real concern
how bad was the temp when rad hose blew??? did it redline hot?-
the upper hose is the one shooting coolant OUT of the engine so it will have pumped it dry in not much time--
how much time do you estimate from problem occured to stopped on side of road--from what speed? 2 minutes 1 minute 5 minutes, crossed the Deleware~

Whats the temp do now- 2 lines below half like before?

to get air out/burping the rad: (try search for burping)
remove the rad cap when engine cold- set heater to HOT
set rad cap on loosely and start engine -let it idle until the driver fan comes on and look at the rad level- ck flow rate thru rad -add coolant as needed

ck the diy section - should be the details in there- my 01 book has you holding rpm at 2000 until fan comes on and off, letting idle again, doing a few times,closing cap tightly, took about 15-20 minutes
ck res level is good at cold mark when cold, and that rubber hoose inside res cap is on good and tight to its nipple-
now drive-
next day ck levels in rad and res bottle

01tl4tl

did you look for a vacuum hose melted somewhere?

have you looked at the oil and coolant for crossover contamination?

jr07871

Thanks for the tips. The hose blew in my neighborhood and the temp never reached 3/4. I drove it home (2 minutes?) and parked until I could replace the hose. Temp now remains always 2 lines below half and does not vary. I have good heat and believe all the air is out. I have checked the oil, no cross contamination, nice and clean. I have looked for a vacuum leak but cannot see, feel or hear one. Car was fine before blown hose and dead battery. The battery is less than 6 months old, the problem was caused by me leaving the key on (I went back to work in another car, came home and realized what I had done). No problems starting since replacing hose and jump starting. I will try the clock fuse tomorrow morning. Thanks

01tl4tl

Lucky is your new name!!
good job getting it stopped qiuickly and so far so good on temp and running
EXCEPT you are still surging??

ck the master vac line that goes to TB, the one with squeeze type hose clamp on it- for melting damage

Even new batteries die and ones that take a hit need to be tested

just because you have good heat doesnt mean its all good inside rad for air
-wont hurt to double ck it-- as a bubble will fool temp sensor and freak thermostat out

next to ck for surge at idle is: IACV idle air control valve on bottem of the TB base- remove cover and disc-- clean
can be done on car with short screwdriver and mirror or remove TB, flip over and work

01tl4tl

to test for vac leaks on hoses you must clamp it with needle nose pliers or similar tool without teeth (prevents hose damage) watch for any changes

and spray carb cleaner at each hose and connection- if idle speed changes when carb cleaner hits it,,that means a leak in the hose

jr07871

OK, I reset the ECU this morning with the clock fuse. No CEL light - figured it may come on an the way to auto parts to scan ECU, but no such "luck". I did have them load test battery - checked OK. Ran all day, no CEL, still fluctuating idle, hunting 1200-1800 while in park or neutral. High idle while in drive but does not fluctuate. Checked for vacuum leaks - nothing found. I may take off throttle body this weekend and clean IACV. Any thoughts between now and then would be appreciated. Is there a procedure to drive while ECU relearns or drive as normal? How long should it take?

01tl4tl

ecu learns how you drive over a week or two- drive however is `normal` for you
BUT-
with the idle still messed up- another reset when thats fixed is in order so it learns correctly

do the IACV cleaning- its been a popular problem this week

jr07871

OK, got it all apart. rod was frozen, cleaned, lubed all seems good now. Before I put i all back together I have a question.
Is anything inside the black plastic sensor supposed to move?
It seems to me that air volume changes the position of the rod which "should" change the position of something inside the sensor. To me, it seems as if the internals of the sensor do not move and I am wondering if this is frozen also. I have not done anything to clean or unfreeze the sensor, afraid to soak electronic components. Let me know if you think I need to try and clean or replace or just put back together as is.
Thanks for your help.

01tl4tl

put it back together

jr07871

Hallelujah, finally the dilemma is over. Re-installed and it started right up with a normal idle. All is well.
Thank you so much for the help and support!

01tl4tl

congrats on the fix,,so you removed the TB and pulled the iacv apart-is that correct? and used what lube?

do a clock fuse reset of the ecu and drive however is normal for you as it relearns,,there is some adaptive learning and programming by the car on how you drive

jr07871

I used CRC to lube, I had disconnected battery during repair so no clock reset needed. I did encounter a problem with the torx screws on the IACV, but used civicdrivr's tip to use a dremel tool to change torx into a slotted screw and that worked perfectly. Thanks again!

01tl4tl

great job- CRC to the rescue
that dremel trick works on the headlight rear cover screws too