North American Turbocoupe Organization



error codes and pcv
Nsw Offline
Senior Member
#1
Hi all,

About a week ago my car randomly started idling at over 1500 rpm. I swapped out the TPS and the problem went away. While I was in there I noticed that my PCV was disconnected where the valve is near the distributor so I went ahead and plugged it back in.

Since re-connecting the PCV my check engine light comes on while driving and its idles slightly rougher then before. I pulled the codes with an Innova code scanner.

I got the following codes
KOEO
81
continuous
42,18,63,72,14


KOER
34,74,77

I did not tap the throttle or break during the test, also the car has not had the egr recall preformed will that cause a 34?
Also while performing the KOER test the code scanner jiggled loose once. After that I held it until the scan was complete.

I have re checked my TPS voltage and it is at .92v and has no dead spots. there was also some oil in the IAC when I removed it, I cleaned it up and slapped it back in.

The car runs great with the PCV disconnected and The check engine light stays off, any ideas on what could be causing this?

is it safe/smart to drive with it disconnected? Its been that way for a quite some time and even passed an emissions test.

thanks for any help
Joe


1988 5speed black every option. 3inch single turbo to tail(stinger), manual boost control. k&n cone walbro fuel pump

1986 xr4ti project car..... way to many mods to list.
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Pete D Offline
Administrator
#2
1. I'd try erasing the continuous memory codes, drive it a couple days, and see what comes back.

2. Where is it disconnected at, the top of the valve or at the bottom? One way is going to be a big boost leak and the other pollutes the environment. There really is no penalty to having it hooked up and working and the "proper" pc valve is cheap. There are downsides to having it not hooked up and working. Just be sure to use a Motorcraft EV-127-A valve
Pete Dunham


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Nsw Offline
Senior Member
#3
thanks for the info Pete,

it was disconnected below the valve. I pulled it out and did the blow through test and it did not leak. I'll put a proper motocraft valve in and see what happens in the next few days
1988 5speed black every option. 3inch single turbo to tail(stinger), manual boost control. k&n cone walbro fuel pump

1986 xr4ti project car..... way to many mods to list.
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Jeff K Offline
Administrator
#4
The disconnected PCV was a huge leak of unmetered air. EEC apparently was able to adapt to this by increasing injector pulse to compensate to keep A/F correct during closed loop operation (high positive long term fuel trims). Hooking it back up eliminated the air leak. Now it is rich, and it wwill take some time for the long term fuel trims to come back down to near zero.

Try this: Disconnect the batt for 15 minutes to clear all the adaptives in the EEC. Reconnect batt and drive under different conditions for a while. Does the CEL come on again or stay off?
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
11 Crown Vic Interceptor
14 Toyota Camry (wifes car)
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Nsw Offline
Senior Member
#5
Sorry for the late reply,

I put in a new pcv and drove it around for a week and the CEL is gone. Like you said jeff it took some time for the computer to adjust.

thanks for the help
1988 5speed black every option. 3inch single turbo to tail(stinger), manual boost control. k&n cone walbro fuel pump

1986 xr4ti project car..... way to many mods to list.
Reply





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