Slows2k

EGR clogging is not an issue with any S2000 because the car has never had an EGR system

R3DS2K

yea i was just posting what alldata said about the code P1399
also i cant get much info about P1399
again from alldata so im guessing this is a honda only code
Honda does not supply a diagnostic flow chart for this code

Togobox

P1399 is SAE , NOT Honda ,

jman

Thanks Guys

It may be worth doing a fuel pressure test as I am still nibbling on the fact that the misfires and Cylinder 1 low PSI could be unrelated as it befuddles me why putting in new injectors last year, "fixed the CEL" for a year. Plus doing a fuel test will provide more data and it never hurts to have lots of data.

Just to give you guys a laugh, last week I decided to try the Dealer route for troubleshooting. They did a compression test and came back saying they needed to replace the entire cylinder head for $5k. I laughed and asked them if they even took a look at the inside of the cylinder before making such a HUGE assumption based on a compression test. They looked confused so I looked confused when they asked me to pay for the compression test.

Togobox

not worth to do anything til you figured out why #1 is low compression.
The compression variation is out of spec. Do you noticed any oil comes out of the PCV ?

jman

I definitely need to fix on the Cylinder Issue first and foremost. Thanks to all for helping to keep me focused.

I have not noticed any oil leakage in the PCV, but have only started checking on it recently. Oil level has also remained level.

Togobox

i wonder once you pull the cylinder head you would know what is going on. Worn pistion rings will cause alot of blow by that often have enough pressure to push oil out of the valve cover, seals etc. might want to remove the pcv , run the engine to see if it's got oil comes out of that hole.

the only way i know the cylinder head is good is to remove it and pressure test it.

Random1

If the root cause of the injector problem is junk in the gas tank then it could be that the junk made your injectors sticky after a year and caused misfires. If you had also cleaned or put in a new gas tank it may have lasted another 50k miles, but who knows since the root cause of sticky injectors, rough idle, and random misfire codes is not know to my knowledge.

kial007

The Honda service manual says to check fuel pressure if you have a random misfire code accompanied by individual cylinder misfire codes (regardless of how many or which cylinders).

jman

Thank you to all for feedback and advice.

I had a chance to chat with Hardtopguy (Jeff) during the week. Like many of us he has seen this scenario before and indicated it is actually two separate issues (compression and misfires).

My next steps for fix are:
- Replace injectors with working used ones
- Flush Fuel System
- Replace both intake and exhaust valve's on Cylinder 1
- While doing all this work keep a careful eye out for any damage in the cylinder head

I am waiting on parts and hope to have the work started in the next week.