I posted this in the Prelude forum and only got a few responses, just want to see if anyone has any ideas on what I need to do if anything to troubleshoot this. Some have also suggested that the gapping of the plugs could also affect this. Please help guys. Thanks

Just wondering if anyone ever got a CEL for having some low comp pistons in their car. Cuz I just started my car and my CEL is throwing codes of 71, 72 and 73 which is misfire detected in cylinders 1, 2, and 3. One of the reasons is it says it may be cause by low comp. Just wondering if that may be the reason so I can try to narrow it down to what it could be cuz their are several other reasons also that may cause it.

 

i had those codes before but they were becuase i needed a valve adjustment. I dont think it has anything to do with your lower compression pistons. Try a compression test.

 

What would a compression test prove?

 

I just finished putting the motor back together so valves were already adjusted to specs, any other ideas???

 

Low compression pistons wouldnt cause that. That code is set because you have a weak cylinder. A compression test woudl tell you if you have a weak cylinder(s)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jared &raquo;</TD></TR><TR><TD CLASS="quote">Low compression pistons wouldnt cause that. That code is set because you have a weak cylinder. A compression test woudl tell you if you have a weak cylinder(s)</TD></TR></TABLE>

Well my car is running perfectly smooth, idles and accelerates strong, no hesitation at all. So you are saying I may have a weak cylinder??? I threw codes of 71, 72, 73 and 74 which is all four cylinders. My block was also resleeved w/ GE godzilla sleeves, bored 2mm over new pistons/rods the whole 9 yards. Plus my head was all upgraded and made to match, valve train etc.

I havent gotten much help w/ this (seems like I am always asking the "hard" questions) I need some help from the "old school" people that used to help me when I first joined. But I am think that it may be due to my IAC Valve. Maybe I need to replace it, since my car stalls out when it comes down from like 4k or something. I cleaned out the IAC valve and so far it seems to not stall out as often. But here are the possible reasons that you may throw codes of 71 and so on.


Ignition System
Fuel Supply System
EGR System
IAC Valve
Contaminated Fuel
Lack of Fuel
Valve Clearance
Fuel Injector Circuit
Low Compression

 

I think valve clearance can be ruled out. Don't you still have really really really old gas lingering around in your fuel system?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybridreams &raquo;</TD></TR><TR><TD CLASS="quote">I think valve clearance can be ruled out. Don't you still have really really really old gas lingering around in your fuel system?</TD></TR></TABLE>

No I have driven over 200 miles already, nobody can give me any ideas???

 

Bump again for some help......anything guys.

I also read another post were the fuel pump may cause this since all four cylinders are throwing the codes. Just trying to see what other people views are on this. Thanks guys.