engine stalls, runs much too rich at idle (CTSC) - urgent

[goldNSX]

It's the first time my quite overserviced car left my stranded in my 10 years of ownership. It's a 91 with around 100k miles, since 5k CTSC low boost, newest version.

I've tried to start it this morning and it stalled within two seconds. Started it again, stalled again. Started it once again, put some throttle up to 2500 rpm for 20 seconds but got very rough idle and some metal clanking sound I didn't like. Stopped it finally.

Until I parked the car two days ago it runned and idled like a champ. It's parked it a closed garage (no mices or birds ).

I've pulled the plugs. They all looked deeply black and were wet (fuel). I've checked the fuel pressure at the filter: 44 psi as usual after turning to ignition.

I've checked the compression of the engine cylinders with a simple tool: 15 bar, very even (220 psi), no problem here.

Ignition coils are pretty new, igniter unit also.

It gets too much fuel at idle.

I've read about cleaning the throttle body and cleaned the area around the throttle plate last winter.

Any hint highly apprechiated.

Addition: I've changed the CTSC and engine oil 100 miles ago. Both levels are between min and max. I don't see a correlation here.

 

[DRIFTER]

Have you checked for vacuume leaks? That solved my fathers wondering idle issues with his CTSC. May want to start there.

 

[whrdnsx]

Map sensor failure. Had it happen a while ago on a CTSC install.

 

[goldNSX]

What shall I say, all is back to normal again. I've unplugged the battery which did a reset. I've unplugged some other plugs too. Looks like an intermittent failure to me.

The map sensor is a good point. I guess I change it precauciously ($350 ). It looks as if some sensors start to fail after 21 years. My speed sensor was acting very strange once but is back to normal for now. Very funny to see 100 mph standing at a redlight.

One question: If a map sensor fails can I still drive the car when the engine is warmed up and running fine?

picture: sparkplug, it was wet when pulled.

Thanks to all.

 

[Hugh]

My speed sensor was acting very strange once but is back to normal for now. Very funny to see 100 mph standing at a redlight.

The VSS is Dorman Part# 911-751
You can Google that and get the part a lot cheaper than through Honda.

 

[goldNSX]

The VSS is Dorman Part# 911-751
You can Google that and get the part a lot cheaper than through Honda.

I already have one in stock.

Hugh, where is your heavy-metal avatar, I didn't recognize you?

 

[Hugh]

Hugh, where is your heavy-metal avatar, I didn't recognize you?

I had to take it down temporarily so I can display my Zombie hunting permit. Haven't you heard? We have had a zombie outbreak here in Florida. Apparently it is spreading because another attack just happened in Maryland. :smile:

 

[otto_joe]

http://www.nsxprime.com/forum/showthread.php?t=150517

1. Check you battery ground.
2. Check your ignition switch.
3. Check to see if your #4 vacuum hose is clear and not clogged up. Two local members were having hard starts and bad idle issues until they cleaned out that hose.

YMMV

Otto

 

[Hrant]

Yes, vacuum hose #4 seems to be the culprit. But per Shad, the fix is not just cleaning it or replacing it; for those with a CTSC, it entails a bit more - using a T connector to minimize the the potential air trap created in the hose at its U form ......

 

[goldNSX]

Yes, vacuum hose #4 seems to be the culprit. But per Shad, the fix is not just cleaning it or replacing it; for those with a CTSC, it entails a bit more - using a T connector to minimize the the potential air trap created in the hose at its U form ......

Thanks to Otto and you for the hint to hose no. 4. What do you mean exactly with the T-junction?

Update: I just came back from testing hose no. 4. I detached it at the junction that comes with the CTSC kit, took the hose that goes down to the charger in my mouth and tried to blow through. It was not possible! I blew longer and stronger et voila: hose was free. A smell of gas was noticable. Reattached it, started it up, runs like a champ again.

I guess we have a winner! Thanks very much! You saved my weekend. Next week the CTSC will be registrated on my car.

One question though. First, thanks to Hrant for sending my pics. But as the hose goes below to the intake mainfold of the supercharger it would mean to dismount it to get proper access to the attached hose. How do you clean it?

 

[Hugh]

How do you clean it?

With the "Godzilla" of hose cleaners......... :biggrin:

<iframe width="420" height="315" src="http://www.youtube.com/embed/mzj3qEli8kc" frameborder="0" allowfullscreen></iframe>

 

[NSX-Barque]

^^ Can you say, High Colonic Irrigation!

 

[RYU]

gold - glad you resolved the issue! that's another win for Hrant! nice work. my guess would have been check the ground wire on the igniter that's bolted to the CTSC intake snout (which was the issue with mine).

how did you clear the hose? You just blew into it so then you blew whatever was in there causing the blockage back into the intake manifold? I've wanted to service this on mine but can't figure out how to go about this w/o removing the blower itself.

 

[Dhalsim]

gold - glad you resolved the issue! that's another win for Hrant! nice work. my guess would have been check the ground wire on the igniter that's bolted to the CTSC intake snout (which was the issue with mine).

how did you clear the hose? You just blew into it so then you blew whatever was in there causing the blockage back into the intake manifold? I've wanted to service this on mine but can't figure out how to go about this w/o removing the blower itself.

I was wondering the same thing. Why not pull the hose off from both ends? I only have the rough idle issue when it gets cold but I think the #4 hose could be the issue.

 

[RYU]

In thinking thru this some more... I'm not running a catch can but I will soon. I have a feeling some of the blow-by oil is flowing back into the TB and down the IM...then some of that is getting into #4. Damn.. I need that catch can.

 

[goldNSX]

In thinking thru this some more... I'm not running a catch can but I will soon. I have a feeling some of the blow-by oil is flowing back into the TB and down the IM...then some of that is getting into #4. Damn.. I need that catch can.

I think the same, it's oil spray.

For now, I just blew air through it but I've planned to inject a small amount of gas with a canula like a nurse injects a medicine into a patients vein. Brake cleaner would work also but gas is better as it will burn better an safer (high octane) and is not as hard to the hose as brake cleaner is.
To prevent blockage I'll use Shad's (at Driving ambition) solution.