Hey, new to forum, but I've been reading here for years. 03 CL w/Auto now at 161k.

Problem only occurs with outside temps above 60(F), and ANY time I drive longer than half an hour. If I sit stopped+idle, or turn car off for more than a few minutes, the vehicle becomes unmanageable.

Idle in P or N - 3000rpm
Reverse - about 1500rpm
Drive - 2100rpm

With those idle speeds, you can't drive the car safely (idling, it accelerates to 35mph) Plus the strain on the non-OEM torque converter (tranny rebuilt at last failure )...

I can regain idle control, if I perform heavy acceleration in gear, off and on for at least a full minute, or let the car sit for half an hour.

No DTCs, Dealer has failed twice to find a cause.

The vehicle is mechanically very well-maintained with a spotless engine compartment, so I can't think of gunk build up anywhere - problem has been around for a year and a half and is getting worse (Winter hides the problem completely, and when the problem started the idle would only go up to 1500 rpm in D )

I don't consider it an IACV issue because the idle isn't erratic and our cars seem to stick to known problems (this is the only problem in 160k that wasn't found on the forum, in fact)

Thanks in advance,

 

Check your throttle and cruise cables for play. They could be too tight causing the throttle plate to stick open a little. A 12 mm wrench will loosen the nuts and you can adjust them how you need.

 

Check for a open wire at the power steering pressure switch.

 

I've had that issue and a mechanic suggested I put a clothespin on the fuel line. Apparently our cars can have heat soak issues and a wooden clothespin absorbs some heat off the metal line.

It works.......If that doesn't do the trick it's most likely the fuel regulator

 

LOL I'm sorry but the thought of hanging laundry off of your fuel rails cracks me up!

 

Checked the cabling, and that looks fine - I'm intrigued by the thought of a metal plate though sticking MusicLevelz5 - Would that be in the actual "throttle body"?

01ACLS, I would think an open on the power steering switch would create a DTC for Power Steering Switch, so can you explain more behind this thought-

I'm all too familiar with heat-soak (which oddly have only affected my Japanese cars over the years) and I'm reluctant to categorize this as that except for your experience OakRoadSteve. I don't want to think that the summer-blend gasoline/eat-soak is causing the issue, and the PCM isn't detecting it as a fault rather just adjusting idle higher and higher to this extreme (today idle went up to a new high of 3200 while my fuel economy is going to a new low lol) - the other reason I'm reluctant is that in all my other experiences with heat-soak in other cars, flooring the car until it smoothed out ended the problem for the drive, as where this will just creep right back up a few minutes later (if in stop-and-go traffic for example).

I can shove a clothes pin on a fuel line and see what happens for the time being -

 

Does not always throw a code.

The power steering pressure switch will adjust the idle through the PCM to compensate for bogging down the engine at low speeds, such as costing around a corner, turning fast as in lock to lock, U turns at low speeds.

I'm just throwing it out there since you seem to be out of options.

Maybe it's default program is to raise rpm to ensure the car have power steering at any speed, even at a stop.

 

Hey Oakroadsteve, (the CL) laughed at your mortal suggestion, and spit out the clothespin. (It's a cruel vehicle like that.)

Having given the idea more thought, I realized the high idle could be the computer revving to the lowest possible point of air/fuel/spark balance with heat-soak fuel, which makes sense.

I'm going to try heat-shielding the fuel lines, actually heat-sheathing wrap.

Available at auto parts stores are the foil-look heat-shield wrappings.

What fuel line(s) should I wrap within the engine compartment?


Thank you everyone.

 

Apparently another Acuraziner had the same issue as you, erratic idle issues. Their problem was air in the coolant system. You might give that a try... repurging the coolant system of air. Unless you're sure there is none.

If one were to wrap their fuel lines, one would only wrap the lines under the plenium.

 

01ACLS, it shouldn't be that - just had a major service requiring all new coolant about 2k mi ago and the problem has stuck around/not changed.

 

Update!

The problem got worse, and after using a Bosch OBDII Engine Analyzer (and still seeing no codes) I was able to see what the computer saw as the problem occurred and what the engine was doing to compensate - which led me to either a faulty Throttle Position Sensor or the IACV (the computer was recognizing a big change in air or throttle input when the problem occurred and compensating with the other).

Either option was a couple hundred dollars (or $5xx for a Throttle Body replacement) and I double checked with NHTSA looking for owner reported incidents on 2003 TLs and CLs sure I would find at least one other owner with the same problem. I found 3, in all three cases, the dealers replaced the IACV and the problem was solved.

So, I'm happy to report my CL lives to see another maintenance cycle.


Thank you all for the help and ideas!