check engine light with high speed driving

[mystican]

OK I know it bad...but this is what happened

1. Raced a Honda RVT 1000 motorcycle...everything was going well... until I inadvertantly hit the redline fairly hard in fourth gear...BOOM...check engine light...power drops off BIG time and I have to OFF/ON the NSX in order to "reset" it...everything back to normal Michigan driving...no more racing...

2. Driving back from "nowhere Michigan" today... I decide to test top speed...everything going well until about 140 MPH...BOOM...check engine light...OFF/ON the NSX...everything back to normal

3. Happens again like number 2 (above) except in fourth gear

4. Happens again like number 2 (above) this time with A/C on and it was approximately 120 MPH...

5. The light doesn't turn on in ANY rpm in third gear...

I have taken the entire TCS unit out of my 1991 NSX (13,700miles)...could this have anything to do with the problem I am having?

I think I intuitively understand why the light went on when I bounced off the rev limiter, but the subsequent high speed straight line driving and resultant "check engine light" I simply do not understand...could it low oil and engine is sensing starvation? Or could it be the TCS disconnection and going over minute bumps in the Michigan roads causing sensitive wheel ratio disturbances?

Could somebody please explain...and

I have learned from my mistake !

 

[Briank]

No way to tell what is causing the CEL check engine light by what you were doing. You need to get the code.


http://www.nsxprime.com/FAQ/DIY/trouble_codes.htm

 

[mystican]

check engine codes found

Ok...little different from the Nissan SE-R...but I got some codes...

3 long blinks...then 6 short blinks= 36=Traction Control? (TCFC)

4 long blinks...then 7 long blinks= 47=fuel pump?


OK so here are my theories:

1. The time I raced the bike and I bounced off the revlimiter in 4th gear caused a fuel pump failure code since that is probably how Honda "rev limits" the engine in order to protect it...

2. The time I opened the car up on the "bumpy" Michigan (I-75)roads...the wheel sensors sensed a "ratio differential" due to the bumps and wanted to "talk" to the TCS unit, but it couldn't...so then BOOM...check engine light...

Questions:

1. Is there something REALLY wrong with my fuel pump or was it just the revlimiter?

2. Should I put the TCS back in...I took it out because I hate the dash light...it started to "act" up occasionally with its own yellow light on the dash (I hear it is pretty common)

3. Any other opinions, suggestions, or constructive criticisms are greatly appreciated.

 

[NSX-Racer]

The kick in of the rev limiter doesn't usualy cause a check engine light or error code - if it would be so I would get it multiple times at the track.

 

[Briank]

Looking at the service manual with a 47 code you could have a problem with your fuel pump, fuel pump resistor, fuel presure regulator, main relay, fuel pump relay, fuel filter, ecu or just a bad connection. Have you ever changed the fuel filter ??

The manual is on line here: http://www.nsxprime.com/FAQ/Reference/1991_svcman/1991servman.pdf

Start on page 275 of the pdf file to trouble shoot a 47code

 

[mystican]

check engine light

Well I went to talk to Devin at Payne technology...he called Mark Basch and told him that...

1. Fuel pump could be going at high rpm...causing lean condition

2. Fuel pump working too hard when pushing the car HARD in fifth gear...consider direct connection to the battery for direct voltage "juice" to the fuel pump.

3. The angle of the steering wheel is part of the TCS system and measures the angle of the wheel when TCS is activated...erase the code and it should not come back...could have activated when I took out the TCS module from the car...

ANYBODY with thoughts?

 

[DanO]

Any relevant mods to your car? Year? When you say “BOOM” do you mean that you hear a “BOOM” or you’re just saying “BOOM” for hyperbolic reasons?

DanO

 

[NSXTech]

Re: check engine light

Well I went to talk to Devin at Payne technology...he called Mark Basch and told him that...

1. Fuel pump could be going at high rpm...causing lean condition

2. Fuel pump working too hard when pushing the car HARD in fifth gear...consider direct connection to the battery for direct voltage "juice" to the fuel pump.

3. The angle of the steering wheel is part of the TCS system and measures the angle of the wheel when TCS is activated...erase the code and it should not come back...could have activated when I took out the TCS module from the car...

ANYBODY with thoughts?

More precisely, I said that with the TCS unit out, you will always have a code 36 as a latent code, because the TCS ECU sends a TCFC signal to the ECU. You don't need the TCFC signal, but because its missing, you will always have a code 36 in addition to whatever else turns on the MIL. The 36 alone will not turn on the MIL, but as a latent code, will always show when the connectoris shunted to find another code. The low fuel pressure was a guess because the code you had was a very generic "fuel system fault", and it pops up on very lean burning. Top of fifth gear consumes alot of fuel per minute and a weak fuel pump may not keep up.

MB

n.b.- top of fifth?? had a drivers licence long?? (sg)

 

[mystican]

check engine light

Thank you MB for your input again...greatly appreciated...

Questions:

1. How do I effectively eliminate the TCS with out tripping the check engine light? I simply don't like it.

2. Should I directly "hot wire" the Fuel pump? The car has only 13,700 miles on it...although a 1991...Can age really make that much of a difference in a fuel pump?

3. I understand the added "stress" to the fuel pump in topping out fifth gear...the situation manifested itself in fourth gear close to the rev limit (~7800 rpm)...Why does it not occur in the third gear...or others?

4. My concern with this whole thread was that I plan on "tracking" the car...and I don't want this to happen at the track in the middle of slight turn...engine goes in "limp" mode and then spin out b/c I was in a slight turn doing over 120 MPH...could be a little dangerous

BOOM...was just for added effect...did not really happened...engine clearly does not like it though...

Yes I still have my license...anxious to get back to the track...

 

[magnus85]

hey i know this is an old thread but I have exactly the same problem with my NSX 91. I've only had the car for a week so I have not had time to check out as much of the problem. the previous owner has recently changed the fuel pump.
any one have any tips on what could be wrong? it would be appreciated =)


// Magnus from Sweden

- - - Updated - - -

Any ideas?

 

[magnus85]

Bump..

 

[jwmelvin]

When you say exactly the same problem, do you mean that you read the same two codes as the OP?

 

[Old Guy]

Which problem, code 36 or code 37? As noted, if it is code 37 it is a fuel system fault. Could be a clogged fuel filter, faulty fuel pressure regulator or other items. I suggest you get the service manual which is available from this site and start working through the trouble shooting procedure set out in the manual.

 

[magnus85]

When I say that yes has exactly the same problem, I mean that when I gas up the car on 4 gear when I come over about 4500rpm (boom) engine is shut off for a short second. or something similar. petrol pump is new changed by previous owners also fuel filter. I think the resistor is also changed. it looks like new!
Sorry I not check error codes before I asked here. will do it as fast as possible!


// magnus from sweden

 

[Old Guy]

If the fuel pump resistor had failed, you would not be able to start the car. At high engine loads (High MAP and RPM values), the ECU energizes the fuel pump relay which by-passes the fuel pump resistor and applies 12 v directly to the fuel pump, increasing fuel delivery at high engine loads. If your fuel pump relay has failed and is not by-passing the resistor, you may not be maintaining the correct fuel rail pressure at high engine loads causing a lean condition.

An easy test is to put a jumper directly across the terminals of the fuel pump resistor thus manually by-passing it. If the problem goes away, you know it is related to the fuel pump resistor by-pass circuit. If the problem does not go away, then something else is at play!