First codes whoopee
Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
First codes whoopee
I got my first SES light today and checked the codes(nice write up Bogus). I got a H74 and a H32. I know the 32 is the EGR but what is the 74(LCD open)?
Now what should I be doing to get these taken care of.My first thought is to reset and see if they come back.What do you think?
Now what should I be doing to get these taken care of.My first thought is to reset and see if they come back.What do you think?
Advanced
Joined: May 2005
Posts: 90
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From: IN
H32 should be the LCD as per the factory manual. As long as the display isn't going dead or acting strange then its probably a loose connection somewhere. I have the same problem on mine so... 
Last edited by flyingvette; Aug 26, 2005 at 06:07 PM.
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
Originally Posted by flyingvette
H32 should be the LCD as per the factory manual. As long as the display isn't going dead or acting strange then its probably a loose connection somewhere. I have the same problem on mine so...
I am assuming that the H32 is from the ECM (4.0) and the H72 is from the CCM (1.0).
Redeasysport - glad you liked it!
Here is the link for everyone else:
C4 Guru - CCM Code Reading 1992-1993
Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Correct Bogus except H74 ,1, H32 , 4 so now what ignore it till it happens again?Geeze I don't want to start playing with the EGR I am still ironing out the tranny.
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by Redeasysport
INow what should I be doing to get these taken care of.My first thought is to reset and see if they come back.What do you think?
RACE ON!!!
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Have it your way. But just because a code was caused by one thing for someone else, doen't mean that you have the same problem. Throwing money at is is the same regardless of the method.
RACE ON!!!
PS. At least I didn't include the link, for YOU.
RACE ON!!!
PS. At least I didn't include the link, for YOU.
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Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Originally Posted by CFI-EFI
Have it your way. But just because a code was caused by one thing for someone else, doen't mean that you have the same problem. Throwing money at is is the same regardless of the method.
RACE ON!!!
PS. At least I didn't include the link, for YOU.
RACE ON!!!
PS. At least I didn't include the link, for YOU.
As alway you are right CFI I know this code has made the rounds here but the search really sucks it only goes back 2 months now wonder when Troy will address this problem.
Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
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From: Myrtle Beach SC
St. Jude Donor '05-'06
Hmmm a really helpfull guy posted this
" The EGR isn't activated until the engine is warm, so that fits. On mine, the return spring weakened with age. The normal amount of vacuum would open the valve too far and cause a lean misfire. A good test, is to make sure it seals well when closed, then disconnect and plug the vacuum line to the EGR and see if you still have the miss."
"During heavy acceleration, the manifold vacuum drops. There is much less vacuum at advanced throttle settings than at a steady cruise. During WOT, the heaviest acceleration, the ECM blocks the vacuum (which is zero or close) from reaching the EGR valve. There is no EGR at WOT."
"The EGR valve is vacuum actuated. The wider the throttle is opened, the lower the vacuum signal available, to pull the EGR open. At WOT, the EGR blocks what is left of the vacuum, which is virtually zero, from reaching the EGR valve."
Thanks CFI for the info
" The EGR isn't activated until the engine is warm, so that fits. On mine, the return spring weakened with age. The normal amount of vacuum would open the valve too far and cause a lean misfire. A good test, is to make sure it seals well when closed, then disconnect and plug the vacuum line to the EGR and see if you still have the miss."
"During heavy acceleration, the manifold vacuum drops. There is much less vacuum at advanced throttle settings than at a steady cruise. During WOT, the heaviest acceleration, the ECM blocks the vacuum (which is zero or close) from reaching the EGR valve. There is no EGR at WOT."
"The EGR valve is vacuum actuated. The wider the throttle is opened, the lower the vacuum signal available, to pull the EGR open. At WOT, the EGR blocks what is left of the vacuum, which is virtually zero, from reaching the EGR valve."
Thanks CFI for the info
Race Director
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From: The Top of Utah
Originally Posted by Redeasysport
Hmmm a really helpfull guy posted this
RACE ON!!!
Thread Starter
Le Mans Master
Joined: Dec 2004
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From: Myrtle Beach SC
St. Jude Donor '05-'06
EFI as stated above code 32 indicates EGR and your previous post(those quotes were from YOUR previous post) was helpfull as most of your posts are.I am not familiar with the EGR operation so it was a good primer.It is good to know general operation of what your about to troubleshoot IMHO. Maybe the code was a fluke so I am waiting for it to occur again as I stated the tranny is my main concern right now and I won't have that straight till next week after I get the TV valve recalibrated. Thank you
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
The key here is reading the code. As what you found from CFI-EFI stated, the code will appear quick, then it's the solinoid, it failed POST... if it takes a while, then it's vacuum or valve related. It could also be a buggered up port - too much carbon.
In all honesty, from my experience, if it is the "valve", it usually is.
I had a code 32, replaced the EGR valve and it has NEVER come back. That was 4 years ago. It would come on during my drive to work... pretty much about 10 minutes after I hit the toll road.
In all honesty, from my experience, if it is the "valve", it usually is.
I had a code 32, replaced the EGR valve and it has NEVER come back. That was 4 years ago. It would come on during my drive to work... pretty much about 10 minutes after I hit the toll road.
Thread Starter
Le Mans Master
Joined: Dec 2004
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From: Myrtle Beach SC
St. Jude Donor '05-'06
In my case it was about 15min into a cruise and as I was turning onto a freeway ramp at low speed.Still don't get the 74 though I never had any trouble with the display and am wondering where it came from.I think it to be highly unlikely that both codes appeared at the same time and I never had an SES before this incident.Would going into diagnostic mode possibly cause this?If so I would think it should not have been a "H" code or is it possible for the 74 to appear and not turn on the SES light?
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
The 74 won't turn on the SES, it would only fire off the SYS.
That's the distinction.
A CCM code fires the SYS. A ECM code fires the SES and an EBCM code fires the ABS/ASR fault lights.
The thing is, for convienence, all 3 codes can be read from the CCM.
That's the distinction.
A CCM code fires the SYS. A ECM code fires the SES and an EBCM code fires the ABS/ASR fault lights.
The thing is, for convienence, all 3 codes can be read from the CCM.
Thread Starter
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
AHH I see said the blind man.So the 74 could have been there for a while.I remember geting a sys a looong time ago and pulled the neg terminal to reset it.Shouldn't that have reset the code?
