HELP/ASAP... Do I need to replace throttle body?

[Richard L S]

I took my 2001 NSX w/ 33k miles to an Acura dealer this morning with the following symptoms:
Car has been experiencing low idle (first line which is 500 RPM) and stalling (becoming more frequent over time) as the RMPs lower when I am comming to a stop and the car is in nutral (i.e., I'm going 40 miles an hour, traffic light turns red, I put car in nutral and apply breaks). This week, check engine light came on after a stall.

I took the car in for service this morning, and was told that the trouble code was P0505 and that they needed to take the following actions:

Replace throttle body ($1,462.15 part), replace gasket and perform decarb process by removing carbon buildup. Total cost for parts and labor is about $2,100.

I read on another post (http://www.nsxprime.com/forums/showthread.php?t=71818) where the symptoms were not identical (but were similar and dealer suggested same work) that the level of work recommended was not necessary and a simple cleaning of the throttle body would correct the issue.

Can anyone help me before I end up wasting money.

Thank you in advance for your replies.

-Richard

2001 NSX-T, Silver
Prior owner of a 1995 NSX-T, Black

 

[btcog82]

I took the car in for service this morning, and was told that the trouble code was P0505 and that they needed to take the following actions:

Replace throttle body ($1,462.15 part), replace gasket and perform decarb process by removing carbon buildup. Total cost for parts and labor is about $2,100.

THEY ARE NUTS!!!!!!!!!
Contact the guys @
www.scienceofspeed.com
1-480-894-6277 / Their number may have changed since they moved, just check the website all their updated info is there

An aftermarket throttle body doesn't even cost that much :wink: , and you could probably do the install yourself:wink: !

 

[Richard L S]

Spoke to the service rep. at the dealer again. He states that they removed and cleaned the throttle body, but that it did not resolve the issue. He also states that the TPS sensor voltage is irregular.

Does this help???

 

[Shumdit]

Spoke to the service rep. at the dealer again. He states that they removed and cleaned the throttle body, but that it did not resolve the issue. He also states that the TPS sensor voltage is irregular.

Does this help???

So is it the throttle posistion sensor or the throttle body? I think they are seperate. I think Larry B needs to chime in here, or I would PM him.

 

[Richard L S]

I think Larry B needs to chime in here, or I would PM him.

I PMed Larry B... let's see what he says.... I also put a call in to Chris at Science of Speed, but he won't be in until the morning.

 

[MvM]

I took my 2001 NSX w/ 33k miles to an Acura dealer this morning with the following symptoms:
Car has been experiencing low idle (first line which is 500 RPM) and stalling (becoming more frequent over time) as the RMPs lower when I am comming to a stop and the car is in nutral (i.e., I'm going 40 miles an hour, traffic light turns red, I put car in nutral and apply breaks). This week, check engine light came on after a stall.
I took the car in for service this morning, and was told that the trouble code was P0505 and that they needed to take the following actions:
Replace throttle body ($1,462.15 part), replace gasket and perform decarb process by removing carbon buildup. Total cost for parts and labor is about $2,100.

I read on another post (http://www.nsxprime.com/forums/showthread.php?t=71818) where the symptoms were not identical (but were similar and dealer suggested same work) that the level of work recommended was not necessary and a simple cleaning of the throttle body would correct the issue.
Can anyone help me before I end up wasting money.
Thank you in advance for your replies.

-Richard

Hi Richard,

Just by coincidence, I just picked up my Science of Speed Big Bore Throttle Body at the DHL warehouse today. It looks absolutely fabulous, and although I have never seen a brand-new factory TB, I would be surprised if one would look any better. The whole TB is wonderfully clean and and the butterfly valve itself is shining like a mirror (if you want I can take some pics). And for the price your dealer wants to charge you you can buy five from SoS and still have some change left.

Have not checked at all yet if the replacement of the TB is something I can do myself but it seems to me like a lot of money for a problem which might be solved ten times cheaper. However, since I don't know what the cause is of your problem, that is just a guess from me.

 

[Briank]

Code P0505 is

IAC Valve, IAC System Malfunction

Can someone with 95 or newer manual look up this one and see what it says? If the TPS is bad then I would expect you would get a TPS problem code.

Having a very low idle indicates to me that the air bypass is clogged so much for the dealer doing a cleaning.

There is also a ground wire the goes from the throttle body to the manifold that may be disconnected which could affect the signal from the TPS.

 

[Bilulan]

This is out of the 97+ service manual. In the 95-96, I don't see a P0505 code. I conclude that it must be the same....

The scan tool indicates diagnostic trouble code (DTC) P0505: Idle control system malfunction

Possible cause:
- Throttle body clogged port, improper adustment
- Intake manifold gasket leakage
- Vacuum leak
- ECT sensor range/performance problem

Troubleshoot flowchart:

Problem verification
1) Start the engine. Hold the engine at 3,000 rpm with no load (Neutral or Park position) until the radiator fan comes on, then let it idle.
2) Check the engine speed at idle with no-load conditions: headlights, blower fan, and air conditioner are not operating. (Turn them off)

Is it 700 + or - RPm? YES : intermittend failure, system is ok at this time.

if no: check for vacuum leaks, throttle body port clogging, ect range/performance and repair as necessary.

.....
thats all the manual says under that code. pg 11-117

 

[ScienceofSpeed]

The issue is most likely caused by blocked tubular passages in the throttle body. The later model throttles seem a little more difficult to get cleaned. We disassemble these, strip (which removes all the carbon deposits), rebuild, and recalibrate the TPS sensor. We can bore the throttle at the same time if you'd like. The throttle looks brand new and all the passages will be clear. No guarantee it will resolve your problem, but it's worked in the past successfully for our customers.

Regards,
-- Chris

 

[Shumdit]

Sounds like they may have a parts monkey for as mechanic. That's a tech who just throws parts at a car until it fixes itself!

 

[D'Ecosse]

I don't know how a TB can require replacement - as Chris says, it probably needs to be more thoroughly cleaned or else there are leaks somewhere.
But a complete replacement? <!--StartFragment -->

 

[Shumdit]

The idiot probably turned the "yellow screw of death" and now is trying to sell a replacement since he can get it back to the right place!

 

[splitz]

The idiot probably turned the "yellow screw of death" and now is trying to sell a replacement since he can get it back to the right place!

Uh, not to sound like an idiot, but what and where is the "yellow scre of death?" I'd like to make sure I avoid it :smile:

 

[Shumdit]

It's the screw that has the yellow "paint" mark on it when it is calibrated. Sometimes techs or DIY'er will turn it and if they have cleaned the engine or TB with something that removes this paint mark, they have no idea where to put it back and then you are screwed in many cases, IIRC.
Chris can chime in with more accurate info.

 

[Larry Bastanza]

It's the screw that has the yellow "paint" mark on it when it is calibrated. Sometimes techs or DIY'er will turn it and if they have cleaned the engine or TB with something that removes this paint mark, they have no idea where to put it back and then you are screwed in many cases, IIRC.
Chris can chime in with more accurate info.

Yes that is true, but in this case the car seems to have degraded over time, if I read the description correctly. It sure points to the throttle body needing cleaning.

HTH,
LarryB

 

[MvM]

I don't know how much they would charge you for the cleaning of the throttle body and I also do not know if that would require the removal of the throttle body from the car.
However, this is what the Big Bore Throttle Body from Science of Speed looks like when you take it out of the box.

It probably is the cleanest part of the whole car after I've installed it... :smile:

 

[Shumdit]

Yes that is true, but in this case the car seems to have degraded over time, if I read the description correctly. It sure points to the throttle body needing cleaning.

HTH,
LarryB

If this is what Larry thinks, I would contact the dealer about it, as he is more then likely 10 times more experienced than most NSX techs (even though cleaning the throttle body does not seem like an NSX specific issue that would throw the tech )

 

[DIMITRIS]

I took my 2001 NSX w/ 33k miles to an Acura dealer this morning with the following symptoms:
Car has been experiencing low idle (first line which is 500 RPM) and stalling (becoming more frequent over time) as the RMPs lower when I am comming to a stop and the car is in nutral (i.e., I'm going 40 miles an hour, traffic light turns red, I put car in nutral and apply breaks). This week, check engine light came on after a stall.

I took the car in for service this morning, and was told that the trouble code was P0505 and that they needed to take the following actions:

Replace throttle body ($1,462.15 part), replace gasket and perform decarb process by removing carbon buildup. Total cost for parts and labor is about $2,100.

I read on another post (http://www.nsxprime.com/forums/showthread.php?t=71818) where the symptoms were not identical (but were similar and dealer suggested same work) that the level of work recommended was not necessary and a simple cleaning of the throttle body would correct the issue.

Can anyone help me before I end up wasting money.

Thank you in advance for your replies.

-Richard

2001 NSX-T, Silver
Prior owner of a 1995 NSX-T, Black

CROOKSSSSSSSS
I AM SERPRIZED THEY DIDNT TELL U THAT U NEED TO REPLACE THE ENGINE ...............$$$$$$$$$$$$

 

[Richard L S]

FIXED IT!!!!!


OK... first, the service rep at the dealer was a complete a$$....
He had told me that they had cleaned the throttle body and the problem was not resolved. I had spoke to Chris at SOS and was ready to have the dealer send them the throtle body for a complete cleaning. Chris told me it would take about 2 weeks to get the TB back. Of course, the service rep. told me that they couldn't give me a loaner for that long (I expected this and had already arranged for another car through a friend who is out of town for some time). Then, I questioned why it would they wanted to charge me $500 for labor when the task of removing and reinstalling the TB should be less than 2 hours of time. At this point, the service rep said to me "First, you questioned the need for the new part. Now, you are questioning the labor charges? Why don't you just pick-up your car?" I said, "No problem, I'll be there first thing in the morning to do so."

I went to an auto part store and picked up a can of throttle body cleaner (figured I'd give it one last cleaning before being without my car for at least two weeks) and then went the following morning to pick-up my car.

When I picked-up my car, it was still stalling (i.e., was on the highway at 60 miles an hour, pressed the clutch down, put it in nutral and it stalled).

After work, a friend and I went through Larry B's DIY instructions on cleaning the throttle boddy. While doing so, it was obvioius that the dealership's service dept. never even removed the tob of the airbox to get to the TB, nor had the hoses been pulled from the TB recently as they were still firmly baked on.

Less than an hour of our time later, the TB had been cleaned out, hoses reattached and airbox reinstalled. The car was a bit rough to restart at first, but once it ran for a minute, we turned it off and it started perfectly.

Then, came the real test... when I drove the car, would it still idle low and stall (telling me to send the TB to SOS), would the CEL reilluminate, or would the car work normally?

Fortunatelly, the idleing was completely normaly in the 800 RPM range. I even tried to push it by reving the engine up and letting it drop to see if that would cause it to stall, but it worked flawlessly.

Bottom line, the service rep lied to me about what they had done to try to correct the issue before recomending a $2,000+ repair and the only work needed was a $5 bottle of cleaner and an hour of time.

What would I do without this site??? I hope this helps others in the future.

Thanks to eveyone who helped with this.

Regards,

Richard

 

[Briank]

Name of the the dealer?

 

[Shumdit]

I agree with BrianK, we need to make sure no one else goes to this dealer as this is at the very least incompetence, and more likely outright fraud.

 

[AutoVation]

Then, I questioned why it would they wanted to charge me $500 for labor when the task of removing and reinstalling the TB should be less than 2 hours of time. At this point, the service rep said to me "First, you questioned the need for the new part. Now, you are questioning the labor charges? Why don't you just pick-up your car?" I said, "No problem, I'll be there first thing in the morning to do so."

Did you pay the $500? If so, I would reverse the charges on that. I would also report the dealer to Acura customer service.

 

[Richard L S]

Did you pay the $500? If so, I would reverse the charges on that. I would also report the dealer to Acura customer service.

The only thing I paid for was an oil change ($85 for synthetic). No charge for any other service and I had a loaner for nearly 48 hours. When I was there on Friday, I left a message to have the owner call me as he knows me. He called me, but I was unable to speak with him at that time and now have more information (as I know it just needed to be cleaned). I will speak with him on Monday and advise him as to this experience.

 

[PhiAlpha44]

So what is the name of the Dealership?

 

[RON98]

wow ... nsx with bad idling problems = sell him a new engine.:biggrin:

just get a can of carb cleaner, unbolt the throttly body yourself, and blast everything out. Dont mess with the throttle body sensor or you'll need to get a voltage meter and recalibrate it. Its ok tho cause you might even need to get it recalibrated.

Also check for a vacuum leak. Thats what happens when more air is coming in then calculated and your car dies.

I dont think anything short of blowing an engine or a broken tranny warrants any repairs above 300$