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Ok guys, I had a headgasket job done. After receiving the car back, It ran ok, but it had a rough idle. The RPM's are steady but the engine shakes like hell. I recently had the motor mounts replaced before the headgasket job but I found the front motor mount was busted (cheap aftermarket). So, I replaced the motor mount with a OEM mount and the shake minimized but is still there. I replaced all of spark plugs and coils and I didn't notice any wetness but they needed replaced. I also had the throttle body cleaned and replaced my dried out air intake hose. It runs like a dream and I'm saving gas but yet the engine shakes especially while in drive. I had the exhaust manifold gaskets checked as well as the valve cover. I won't go back to that particular shop because they were the reason I needed a headgasket job in the first place (long story). I had it checked for vaccum leaks as well. It is not throwing any codes and its not missing. Could it need a valve adustment? 173k miles.
 

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Were there any symptoms prior to the headgasket replacement? Did they replace anything else?
 

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Discussion Starter #3
Were there any symptoms prior to the headgasket replacement? Did they replace anything else?

No issues with idle prior to. To add to this story. My original visit was to replace all motor mounts. When I drove my X home it began to run hot. Turns out now the radiator is busted, so I blame them, they blame the age and mileage. They bought the new radiator, I paid for the labor. I drive my car home, things are ok for a few days. Even took it on 4hr rd trip. Then it began to run hot again! Still no rough idle! One morning I start it up, i get a huge white cloud of steam from the tail pipes. I know that is a bad sign, but it runs ok so I drive it to the shop and it begins to run hot on the way. They looked it over and added anti-freeze. My next question, where is the anti-freeze going? They say it must be a leak, I say well my tail pipes were steaming and he blamed the temp. I drive off. Next time I try to start the X. Nothing. I knew my gasket was gone at that point. I had the X towed to them and played the blame game again. They put a gasket kit on it and shipped the heads to a machine shop to make sure nothing was warped. All was good they say, and they put her back together and now I have the shakes!
 

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So is the shake at all speeds? Is it more prevalent at a certain speed. Also to take some things out of the equation can you tell us if it is smooth sounding at the end of the exhaust, no misfiring happening or rough sounding.
 

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So is the shake at all speeds? Is it more prevalent at a certain speed. Also to take some things out of the equation can you tell us if it is smooth sounding at the end of the exhaust, no misfiring happening or rough sounding.

Only while in idle. It is more noticeable when in Drive vs Park. It runs smooth as butter when I press the gas pedal either in Park or driving, No misfiring or rough sounds, but when I come to a stop, I feel the shakes.
 

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Discussion Starter #6
Now that I think about it, I hear a sound in the exhaust, especially in the mornings as if it needs to warm up like a putt putt sound, it goes away once it warms up somewhat and it seems the idle is worst when the putt putt sound fades away from the tail pipes.
 

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It they/you cleaned throttle body to you might need to reset idle position of throttle plate. Not a big deal. There was a such thread recently

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White smoke when starting the engine. Should disappear quickly. If you see white smoke coming out of the car exhaust pipe in thin wisps, but it's only when you start the engine, then there's no need to worry. This is due to an accumulation of condensation that finds its way out through the exhaust pipe Coolant or anti-freeze leakage.



Constant white smoke while driving or Thick white smoke. If white smoke continues to come out of your exhaust while the car is running, and not just when you start it, it may be leaking coolant which is then being burned. Then possible warped head or blown head gasket. Check your oil dipstick and oil cap underside for possible contamination, chocolate milkshake. Do not start if it is.


Them adding coolant might be to top it up as they did not run it long enough to have it circulate everywhere. check it daily next few days to ensure it isn't leaking. There a multiple possibilities but lets hit the easy ones first that you can check. The first thing at this point is to check vacuum hoses. They had the heads off so there is a very real possibility that one of the vacuum hoses was not installed properly which could/would give you rough idle. The computer can adjust for it when you apply gas so shake potentially goes away. Just inspect your hoses , cut a piece of garden hose couple feet long and listen to your lines and connections for excessive noise "vacuum".



The motor mount you said was replaced and it would cause shake and thumps while driving, so you can pretty much rule it out and you said it was changed. The spark plugs you said you had replaced. Only thing here is if they bought the fake plugs online and one of them has given out. Lots of how to tell fake NGK plugs, champions etc online. Just saying that a bad plug could cause the shake or one that is not tightened properly. Bad coil would cause a shake but you would expect it rough running in drive also and you say it is smooth when driving. so you can rule coil out unless you replaced them with the cheap Chinese ones for $35.00-65.00 a set? Then suspect them.



Clogged air filter would be a culprit also so check it out clean replace. Bad "MAF" mass airflow sensor would also be suspect! disconnect the plug to it with vehicle running, if engine dies it is your problem. You can try to clean it with a Can of MAF sensor cleaner. Pull it out and spray it only.... multiple times "do not" touch it or try to clean it with brush. If has o-ring check it for wear if need be replace with new o-ring. Reinstall and re connect harness. Does not hurt to clean it anyway if you have not done so. I clean mine every other year when doing oil change.


Throttle body as mentioned above if they played with it when cleaning it . needs reset. Lastly a dirty or failing oxygen sensor will cause a rough idle also which the computer will try to compensate for but you "Usually will get a check engine light" . You can test your oxygen sensors with a volt meter lots of diy on you tube.
 

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when your head gasket failed you had coolant vapors going thru your exhaust right! your exhaust then goes thru the EGR valve! with that being said your EGR my be stuck slightly open because of the coolant passing thru it, with a stuck EGR it usually only effects the idle
 

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Discussion Starter #10
White smoke when starting the engine. Should disappear quickly. If you see white smoke coming out of the car exhaust pipe in thin wisps, but it's only when you start the engine, then there's no need to worry. This is due to an accumulation of condensation that finds its way out through the exhaust pipe Coolant or anti-freeze leakage.



Constant white smoke while driving or Thick white smoke. If white smoke continues to come out of your exhaust while the car is running, and not just when you start it, it may be leaking coolant which is then being burned. Then possible warped head or blown head gasket. Check your oil dipstick and oil cap underside for possible contamination, chocolate milkshake. Do not start if it is.


Them adding coolant might be to top it up as they did not run it long enough to have it circulate everywhere. check it daily next few days to ensure it isn't leaking. There a multiple possibilities but lets hit the easy ones first that you can check. The first thing at this point is to check vacuum hoses. They had the heads off so there is a very real possibility that one of the vacuum hoses was not installed properly which could/would give you rough idle. The computer can adjust for it when you apply gas so shake potentially goes away. Just inspect your hoses , cut a piece of garden hose couple feet long and listen to your lines and connections for excessive noise "vacuum".



The motor mount you said was replaced and it would cause shake and thumps while driving, so you can pretty much rule it out and you said it was changed. The spark plugs you said you had replaced. Only thing here is if they bought the fake plugs online and one of them has given out. Lots of how to tell fake NGK plugs, champions etc online. Just saying that a bad plug could cause the shake or one that is not tightened properly. Bad coil would cause a shake but you would expect it rough running in drive also and you say it is smooth when driving. so you can rule coil out unless you replaced them with the cheap Chinese ones for $35.00-65.00 a set? Then suspect them.



Clogged air filter would be a culprit also so check it out clean replace. Bad "MAF" mass airflow sensor would also be suspect! disconnect the plug to it with vehicle running, if engine dies it is your problem. You can try to clean it with a Can of MAF sensor cleaner. Pull it out and spray it only.... multiple times "do not" touch it or try to clean it with brush. If has o-ring check it for wear if need be replace with new o-ring. Reinstall and re connect harness. Does not hurt to clean it anyway if you have not done so. I clean mine every other year when doing oil change.


Throttle body as mentioned above if they played with it when cleaning it . needs reset. Lastly a dirty or failing oxygen sensor will cause a rough idle also which the computer will try to compensate for but you "Usually will get a check engine light" . You can test your oxygen sensors with a volt meter lots of diy on you tube.

I was confident the gasket was blown before the shop folks where. The smoke filled my garage to where I could not see and it was open. That has never happened before. In addition, I failed to mention, I steamed half way to the shop and it went away by the time I reached the shop. So, they never saw the steam and only added coolant.


I'm not receiving any codes with this rough idle. If the EGR port is stuck, would that throw a code? As far as the throttle body cleaning, we sprayed the cleaner directly into the intake port and disconnected the fuel line and allowed the X to drink directly from the cleaner bottle. We didn't touch anything on the throttle body itself. We, reconnected the fuel line and raised the RPM's to flush it out. That was it! as far as the throttle body. It made a great difference, but yet the rough idle exist. If a new EGR fixes this, that would be great. However, shouldn't I have a code. One other thing. before the headgasket job, I used to get a emission check engine light constantly. It was bank 2 of the catalytic converter. I still had the code when I got the car back. When I changed out the plugs and coils, I had one damaged coil that I'm sure was arcing., anyways, the code has gone away forever! Just a side note.
 

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I'm not receiving any codes with this rough idle. If the EGR port is stuck, would that throw a code? .....
It did in my X when a 5 mm diameter piece of carbon kept the EGR opened. I got rough idle and a code, don't remember which code though.
 

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It did in my X when a 5 mm diameter piece of carbon kept the EGR opened. I got rough idle and a code, don't remember which code though.
when my egr went bad it threw no code and the idle was very rough, maybe if i drove it a few more days it might have threw a code?
ive heard of other people having a bad egr with no code / engine light
 

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EGR Valve Stuck in the Closed Position An EGR valve that is stuck in the closed position will raise the temperatures in the combustion chamber, creating a knocking or pinging. This is especially noticeable in situations where the vehicle is accelerating or cruising. EGR valves stuck in the closed position are especially dangerous for vehicles equipped with turbos since the high temperature and constant exposure will eventually cause the turbo to seize. EGR Valve Stuck in the Open Position If the EGR valve is stuck in the open position, the vehicle will experience a rough idle or frequently stall. If the valve is not completely stuck open but never achieves a tight seal when it closes, the engine can "miss" or shudder because of the improper mixture of the combustion elements. EGR Valve Opens Too Much or Too Soon Sticky EGR valves that open too much or too soon will cause the vehicle to stumble or hesitate when accelerating. Experiencing a loss of power, when accelerating, may also be a symptom of a sticky EGR valve.



What Are the Signs of a Bad EGR Valve?



https://www.wisegeek.com/how-can-i-tell-if-my-egr-valve-needs-to-be-cleaned-or-replaced.htm



4 Signs your EGR Valves are Failing



you can determine if the tell tale signs are present and if you need to replace or try cleaning your EGR first.
 

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Discussion Starter #14
EGR Valve Stuck in the Closed Position An EGR valve that is stuck in the closed position will raise the temperatures in the combustion chamber, creating a knocking or pinging. This is especially noticeable in situations where the vehicle is accelerating or cruising. EGR valves stuck in the closed position are especially dangerous for vehicles equipped with turbos since the high temperature and constant exposure will eventually cause the turbo to seize. EGR Valve Stuck in the Open Position If the EGR valve is stuck in the open position, the vehicle will experience a rough idle or frequently stall. If the valve is not completely stuck open but never achieves a tight seal when it closes, the engine can "miss" or shudder because of the improper mixture of the combustion elements. EGR Valve Opens Too Much or Too Soon Sticky EGR valves that open too much or too soon will cause the vehicle to stumble or hesitate when accelerating. Experiencing a loss of power, when accelerating, may also be a symptom of a sticky EGR valve.



What Are the Signs of a Bad EGR Valve?



https://www.wisegeek.com/how-can-i-tell-if-my-egr-valve-needs-to-be-cleaned-or-replaced.htm



4 Signs your EGR Valves are Failing



you can determine if the tell tale signs are present and if you need to replace or try cleaning your EGR first.

Before replacing the plugs and coils, it did go into limp mode a few times while in idle. I will start with replacing the EGR valve. I had all of the vaccum hoses checked already.
 
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