Idling Rough, Especially in the Morning - WITH CODES!

[NP SHO]

Ok, so over the past 2 weeks or so I've noticed that my SHO has been idling rough in the morning when I go to start it. It'll start right up with no problem, idle high, but when it drops back down to normal idle it tends to stall about 80% of the time. Finally used the paperclip method this morning and pulled the following codes:

KOEO
----------
111 - System Checks OK

KOER
----------
136 - O2 sensor not switching/system lean Left or Front HO2S - Fuel Control
411 - Idle speed system not controlling idle properly (generally too high) - ISC
536 - Brake On Off open or shorted to ground - BOO
538 - System did not receive "goose" test

CYLINDER BALANCE TEST
----------------------------
1 (I'm assuming this is supposed to be 10) - Problem with cylinder 1
4 (I'm assuming this is supposed to be 40) - Problem with cylinder 4



I had to recently "rebuild" one of my plug wires and I'm sure the rest could stand to be replaced as well. Could this be the cause of my problems? Once it warms up it seems to idle ok. The only other thing I notice is that it may be underpowered when driving, but that might just be paranoia. lol

Any help would be GREATLY appreciated.


PS - I pulled the code definitions right from

here: http://www.shophoenixproject.com/eec/eec.htm
- and -
here: http://www.shophoenixproject.com/eec/code3.htm


Thanks again!

 

[luigisho]

It's tough to get to the bottom of stuff with suspicious plugs and wires as they can throw off alot of stuff. Usually a code 411 would point to a failing IAC or vacuum leak. That's with good ignition.

 

[NP SHO]

I think I'm going to change my plugs and wires tomorrow and try running the test again. Thanks for the input luigisho. :thankyou:

 

[luigisho]

While you're at it, clean your IAC and MAF filament since that is close to free and might help the car run better in the process.

 

[NP SHO]

I cleaned the MAF about a month or two ago, but I can always do it again. Can I use my MAF cleaner to clean the IAC or is there something else I should use?

 

[luigisho]

I would use throttle body or carb cleaner. Cleaning does not always mean fixing a malfunction unit. It just works sometimes.

 

[NP SHO]

I understand, but at this point it's worth a shot. Picking up new plugs and wires tomorrow and I'll clean the MAF and IAC while I'm at it. I'll let you know how I make out. Thanks again!

 

[NP SHO]

OK, did plugs and wires today to try to fix this idle issue. Now I get the following codes:

KOEO
------------
111 - System Checks OK

Then a long pause and then I get:
219 - SPOUT circuit failure, timing defaulted to 10 degrees - follow code 213 diagnosis
(213 - Ignition SPOUT or SAW circuit open or shorted - Ignition Systems)
Due to the pause I believe this is a stored code, but I had the battery disconnected the whole time I was doing the plugs and wires so I thought all the stored codes would be cleared.

KOER
----------
536 - Brake On Off open or shorted to ground - BOO
538 - System did not receive "goose" test (WTF is a "goose" test?)

Cylinder Balance Test
---------------------------
Shows problems with cylinders 1 & 3 but as soon as the engine cools I'm going to check that the wires are tight. I have a feeling this may be the culprit.

Any insight on all of this? Any help is appreciated.

 

[NP SHO]

Anyone?

 

[luigisho]

Those 2 codes are due to operator error. Bookmark the faq main page for future ref.

http://www.shotimes.com/php-bin/mod...le=article&mode=thread&order=0&thold=0&sid=83

 

[luigisho]

Clean the idle air control valve and then check your DIS and PCM. If the plugs and wires are good and the IAC checks out I would look at the DIS module and then the PCM for faults. Have you had anything off lately? Vacuum leak?

 

[rubydist]

Due to the pause I believe this is a stored code, but I had the battery disconnected the whole time I was doing the plugs and wires so I thought all the stored codes would be cleared.

you are correct that it is a stored code, but it could have been stored after you restarted the engine after your work.

how long was the battery disconnected? most of my cars will reset codes after as little at 5 minutes of battery disconnect time, but my red 94 has always taken overnight disconnect time to clear stored codes. (hint - if you start it up and the radio has remembered the presets, your pcm has not reset codes. if the radio is reset, then most likely the pcm is reset also.)

double check to make sure you have wiring on the plugs correctly - some of the manuals give the wrong wiring diagram.

 

[NP SHO]

I am going to run the test again today. I don't think I was giving it enough gas at the beginning of the test and the BOO switch wasn't secure on the brake pedal, so that should take care of those two codes.

Clean the idle air control valve and then check your DIS and PCM. If the plugs and wires are good and the IAC checks out I would look at the DIS module and then the PCM for faults. Have you had anything off lately? Vacuum leak?

I just replaced the plugs and wires with new yesterday. I will double-check the IAC and DIS today, though.

you are correct that it is a stored code, but it could have been stored after you restarted the engine after your work.

how long was the battery disconnected? most of my cars will reset codes after as little at 5 minutes of battery disconnect time, but my red 94 has always taken overnight disconnect time to clear stored codes. (hint - if you start it up and the radio has remembered the presets, your pcm has not reset codes. if the radio is reset, then most likely the pcm is reset also.)

double check to make sure you have wiring on the plugs correctly - some of the manuals give the wrong wiring diagram.

I probably had the battery disconnected for a good 4 or 5 hours. The wiring diagram I used is the one at the bottomg of the worksheet when you're doing valve shims. I didn't do shims or anything, just used the diagram at the bottom of the sheet. I got this from the SHOSource website.

My main concern is the cylinder fault codes. Could these be from the DIS?

 

[NP SHO]

...and how exactly would I go about testing the DIS?

 

[luigisho]

I'm not one to poke and probe the thing. Make sure all the connectors are on correctly, inspect the unit for cracks and damage, and check the grounds are in place. I would look for someone to do a quick swap if I suspected a faulty unit.