I know this is a common problem but I have gone through 20 pages of problems without seeing this and I just dont have time to look all day. Also the search feature rendered a bunch of irrelevant results simply by typing "idling up and down". So I recently replaced my head gaskets after my previous heads warped somehow. I put good heads back on it along with new head gaskets. I took my time and hooked everything back up as it should be, but after the change my car now idles up and down when in park and also idles around 1500 when in drive. I've checked every vacuum hose I have. Changed the MAP sensor, cleaned out the throttle body with carb cleaner and put a new gasket on the throttle body. I always see the IACV mentioned on older models. Is there an IACV on the 3rd gen TL? I can't find anything explicitly calling any part an IACV for 3rd gen. I just bought intake manifold gaskets and an intake plenum gasket that I have yet to change, but other than that, any ideas? Can i use a fog machine to find the problem? Don't have a lot of money to keep dumping into this thing. Thanks in advance.

 

Anyone?

 

you are sure the timing belt teeth/marks lined up properly? Did the block get resurfaced? If not, the block could be warped where the heads mate even though the heads are flat.

 

Erratic idle is usually due to unmetered air entering the intake's path. Check all vacuum hoses again and make sure the rubber intake hose isn't cracked. And state here if you torqued down all intake manifold and top cover bolts properly in the correct sequence in multiple steps, if you didn't, there would be air leak between the intake manifold and the lower runners also.

 

I am surprised nobody has recommended bleeding all of the air out of the cooling system; that's the first thing I'd do in a situation like this.

 

Did you perform engine idle re-learn procedure? I am surprise to see people easily over look that.

 

Good day to everyone at acurazine. I have gained immensely from this forum and if my memory serves me correctly, I haven't made any post up until this time. Now i need your help. To cut the long story short, here is the genesis of my travails.

1. I own an Acura tl 2004. I discovered that the radiator is weak. I was planning to replace it before tragedy struck. Below is the picture of the condition of the radiator.
2. I was on the highway cruising at 110 kmp/68mph and i suddenly noticed a drop in power. Before I could blink, the temperature gauge started rising. I was about turning off the ignition before the car switched off on me. I managed to park to a safe distance and pop open the hood. alas, i saw thick smoke of what looks like engine oil. in addition to this, my radiator was completely dry of coolant. wen i removed the rad, the leak was coming from the center.
3. I called my mechanic who asked me to allow the car to cool down and start it. when I did that, it started but sounded so badly and it won't even move. i had to switch it off. it was confirmed that the head gasket is blown.

PART TWO OF MY TRAVAILS
By the way, i am very good at troubleshooting and DIY(Especially ones that has to do with sensors) i have an above-average obd scan tools with specialised honda software that can read data stream, clear abs, srs and a host of other errors that the regular obd tool won't clear.

1. I have the vehicle towed to the mechanic who replaced the gasket. Now, the vehicle won't start. When we lose the plugs. I released that everything was fouled with fuel. I asked why and he said it was because they primed the fuel pump by spraying fuel on wherever to ensure the car starts quickly. I was scared as it appeared as if the car has zero compression.
2. H continues attempting to start it and after running down 3 batteries, and 12 plugs, the car started. however, it dies immediately. Now, they removed the plugs and heated them and the car would start only when you press the gas pedal. However, the car refuses to idle normally. When it is idling and you rev it, the rpm drops and the engine stalls(if it is a cold start). When the car has warmed up sufficiently, it will idle better and run fine. In all honesty, I do not notice any loss of power when accelerating or speeding. My problem is 100% on the hard starting especially when cold where I will have to crank for seconds or a minutes before it starts and once it starts, it idles rough with rpm going up and down between 1000 and 500.

THE STEPS THAT I HAVE TAKEN SO FAR
I scanned the vehicle and initially got the following codes:
1. 03-02(P0108) Manifold Absolute == This when away on its own after driving around for a while
2. 153-01(p0172) Rear bank fuel= (This also went away after cleaning the IAT sensor)
3. (P0175) This keeps reappearing intermittently especially after a hard cold start. I am confused as to what it means or how to fix it
4. (P0113) IAT Sensor circuit high (I fix this by cleaning the IAT sensor located on the throttle body with cab cleaner
5. i changed some of the ignition coils and the vibration reduced when cold and the idling is almost perfect when hot.
6. I removed all the plugs and none were fouled but two were misgapped and one has a broken electrode. Changing the plugs fix the requirements to press gas before the vehicle starts. Note: prior to my changing the plugs, i must press the gas pedal if I want to start the vehicle otherwise it will crank and attempt to start without starting.

I TOOK IT TO ANOTHER MECHANIC FOR RE-ASSESSMENT
My more reliable mechanic reassessed the timing belt and said it was off by a tooth. He claimed to have adjusted it correctly. When we started the vehicle without the drive belt, it started and idled smoothly. Sadly, when we installed everything, the rough idling with noticeable vibrations resumed.
2. My mechanic now concluded that the gasket jb was badly done that the person did not probably grind the valves. He said he needed to redo it and grind the valves or replace it if damaged. He said the valves are the reasons for the cold hard start and the thumping vibration during cold idle.

THE CURRENT SITUATION OF THE VEHICLE

• No more code on the vehicle at the moment
• The AT is very responsive and sharp
• The engine sounds awesome when revved
• It manages to start now without having to press the gas pedal
• During a cold start, starting is a bit hard
• When the engine is cold, the rpm fluctuates and it idles very low and often stalls
• It has never stalled on me when the engine is warm. Even with the AC on, as long as the engine to reach the operating temperature, it won't stall. I do on the ac at idle speed and the ac works perfectly without the engine stalling. Also, there is no strange noise when the ac is run at idle speed. However, if it tries switching on the ac before the engine gets warm, the engine will stall. In addition, if I attempt putting it in reverse or drive immediately after starting the car, the engine will stall.
• Apart from the rough idling, the engine vibrates and the vibration is felt all through the body of the vehicle.
• I am not hearing any tapping noises like that of a loose valve.

IMPORTANT QUESTIONS TO ASK

1. Is my mechanic correct, can a damaged value rod/train/head be causing this hard start, rough idling and low rpm? I don't want to be ripped off only to be back to square 1 or worse. he said he would need to replace the gasket and do everything all over.
2. Can a dirty EGR Valve or EGR port cause this issue? I am yet to do this. But i think i should get a code if this is dirty. am I wrong?
3. Can a non-premium fule cause this issue? Note: I have never used a premium fule in it before because we don't have anywhere I stay. I, however, used octane booster without any difference in performance.
4. Can dirt in the throttle body be responsible? If yes, I sincerely need a guide on how to clean it safely without damaging the butterfly tongue.
5. How can i solve the (P0175) error for good? where is the sensor causing this error located?
6. Finally, if my assumptions and that of my mechanic is wrong, how can I get my vehicle back to normal idling. It still currently runs fine.

BTW: when the head was opened, the pistons were saved even though coolant mixed with the motor oil.

 

So much for that.

You should start your own thread.


You can do a compression test to see if the valves are bent. The mechanic should have tested it to confirm before selling an expensive job. Maybe find another mechanic.

No more codes after driving a while codes?

A dirty throttle body can cause a rough idle.

 

I already started a thread but no response yet.

I don't have any codes. However, i get 154-01(P0175) code intermittently and only during cold start.