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Checked Codes tonight help me decipher please

  • Thread starter Thread starter cheese_05_70
  • Start date Start date Oct 14, 2009
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cheese_05_70

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Oct 14, 2009
#1
  • Oct 14, 2009
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I got KOEO Codes of: 21, 24, 67. KOER of 21, 91 I think 21 was just because of it not being warm on the KOER. After KOER codes i blipped the throttle and put it into Cylinder balance test and got a code 5. I got good compression in the cylinder so what else? I think I did this right. Thanks any comment or suggestion greatly apprieciated.

Mods to car:
306
windsor sr. heads
e-303 cam
typhoon intake
1.6 rr stud mount
24# injectors with match pro-m meter
hooker shorty headers
Cai
deleted ac and smog
 

liljoe07

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Feb 18, 2009
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Oct 14, 2009
#2
  • Oct 14, 2009
  • #2
Makse sure the engine is at least 160° then run the test again. See if code 21 and 24 goes away.

For code 91. thats a driverside 02 lean code. Make sure you dont have any vacuum leaks or exhaust leaks. If not verify the sensor has a good power and ground. Then test the 02 signal voltage at ECM PIN 43. it should be switching from about .2v-.9v. If not then you either have a bad sensor or wiring to the sensor.

You can also try removing the 02s and switching just the sensors around in the H-pipe. Then run the KOER test and see if code 41 shows. If code 41 shows, then the sensor is at fault most of the time.

Do you have any smog stuff on the car?
 
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cheese_05_70

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  • Oct 15, 2009
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Ok first of all your just who i wanted to talk to i hijacked another thread and it died lol.
Here is what i asked in that thread might be part of my problem I dont know
I have a car that was a 4 cylinder auto and converted it to a 5.0 5 speed with an automatic O2 harness not sure about the engine harness if it was an auto or 5speed. What do I need to check on the O2 harness? and how do i tell if i messed something up in the computer by frying the NSS or NGS? what does those even mean? It runs ok but it wants to die when its cold and hessitates at times.

all smog gone ac gone Im not too worried about code 21 and 24 at this point because i think the are from not being warm and me fiddling around with my car. 91 is where the problem is i have a misfire on #5 cylinder i replaced the injector because i thought it might be leaking that was when i first put it together. Tell me what to check and how to do it. where do i check the o2 for power and ground at the o2 or is under the hood by the fender apron good enough?
also how do you like your system max intake? and time slips or power numbers?
thanks
 

liljoe07

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Oct 15, 2009
#4
  • Oct 15, 2009
  • #4
cheese_05_70 said:
Ok first of all your just who i wanted to talk to i hijacked another thread and it died lol.
Here is what i asked in that thread might be part of my problem I dont know
I have a car that was a 4 cylinder auto and converted it to a 5.0 5 speed with an automatic O2 harness not sure about the engine harness if it was an auto or 5speed. What do I need to check on the O2 harness? and how do i tell if i messed something up in the computer by frying the NSS or NGS? what does those even mean? It runs ok but it wants to die when its cold and hessitates at times.

all smog gone ac gone Im not too worried about code 21 and 24 at this point because i think the are from not being warm and me fiddling around with my car. 91 is where the problem is i have a misfire on #5 cylinder i replaced the injector because i thought it might be leaking that was when i first put it together. Tell me what to check and how to do it. where do i check the o2 for power and ground at the o2 or is under the hood by the fender apron good enough?
also how do you like your system max intake? and time slips or power numbers?
thanks
Click to expand...

If you still have the Auto ECM, your fine. Most of the time if the ECM gets damaged, it would have shown in the Codes. You wind up with damn near every sensor(02, MAF, VSS excluded) throwing a code. Lots of times the ECM wont even throw codes. But you seem fine as off now. Like I said, if you have the Auto ECM. Your fine. If not, and you have the A9L or other 5 speed ECM, then your lucky so far. The ECM usually fry's during a prolonged cranking case.

The easiest way is just to unhook both 02's and put the driver side in the passenger side of the h-pipe and the passenger side 02 in the driver side of the h-pipe, then run the KOER codes again. If 41 shows. Its the sensor on most occasions.

The mis fire may be causing the lean code.
 
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cheese_05_70

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I will try that also what are the checks to see if it is working properly because i have a feeling the misfire is from a lean code and it is fouling the plug becasue it is wet and black. Im gonna try to check the voltages at the same time if i can if i know them. I have the a9l thanks
 

liljoe07

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#6
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Posted via Mobile Device

Since you have the A9L ECM. You may want to unhook the ECM, find PIN 46 on the ECM harness. Hook a voltmeter to it and a ground, and do a cranking voltage test. If no voltage shows up. Then your good. That means you have the correct 02 harness.

Swap O2's first, and see what the codes show. If you still get code 91, then move on to the Mis-fire.

Pull the plug out on that cylinder,and make sure its firing through the plug.

Is only that plug the one that's gas fouling?
 
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cheese_05_70

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liljoe07 said:
Posted via Mobile Device

Since you have the A9L ECM. You may want to unhook the ECM, find PIN 46 on the ECM harness. Hook a voltmeter to it and a ground, and do a cranking voltage test. If no voltage shows up. Then your good. That means you have the correct 02 harness.

Swap O2's first, and see what the codes show. If you still get code 91, then move on to the Mis-fire.

Pull the plug out on that cylinder,and make sure its firing through the plug.

Is only that plug the one that's gas fouling?
Click to expand...



Posted via Mobile Device yes number five cylinder only its black on the plug all others are brown on that side the right side is perfect. could my rpckers be adjusted too tight on that cylinder when you hammer down it runs good but after cruising for a bit it starts to hesitate
 
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cheese_05_70

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Posted via Mobile Device also if it helps the o2 only has about 7000 mi on them
 

liljoe07

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#9
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Posted via Mobile Device

One problem at a time here OK?

Focus on the 02 code.
 
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cheese_05_70

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Sorry just answering your questions and giving you more information about my car that way you can help me lol. thats what im most worried about too is the 02 code. so we are both together. thanks
 
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cheese_05_70

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  • Oct 15, 2009
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cheese_05_70 said:
Posted via Mobile Device also if it helps the o2 only has about 7000 mi on them
Click to expand...



Posted via Mobile Device

well i didnt get a chance to swich o2 but i got a whistle like a supercharger coming from the intake on number five lower intake gasgket or rocker too tight
 

HISSIN50

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#12
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I like Joe's one-code-at-a-time approach but I might check real quick to see if that misfiring cylinder's injector is stuck open. Seems like you're tossing a lean code on that same bank. Checking the injector's electrical-side takes but a minute and should not derail the rest of the diagnostics.


EDIT: NM. looks like you found another issue on that cylinder.
 

liljoe07

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#13
  • Oct 15, 2009
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HISSIN50 said:
I like Joe's one-code-at-a-time approach but I might check real quick to see if that misfiring cylinder's injector is stuck open. Seems like you're tossing a lean code on that same bank. Checking the injector's electrical-side takes but a minute and should not derail the rest of the diagnostics.


EDIT: NM. looks like you found another issue on that cylinder.
Click to expand...

I agree about the injector. The fact that one is gas fouled, indicates a stuck injector or incorrectly adjusted rocker.

The code 91 should affect every cylinder as far as injector pulsewidth is concerned.

Swaping the 02's around would probably still result in code 91, as that whistle points to a Vacuum leak.


Op: try spraying carb cleaner around the area where its whistling while the engine is running.
 
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cheese_05_70

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Sorry Im not spastic I promise im just bascially brainstorming out loud and posting what I find.
Hissin when I first got it running I had this same problem so I bought a new injector and put it in number 5 no better. can i check the resistance of the injector to be sure its closing?

Joe thats what i was thinking about the lean 91 code that it should affect all cylinders but 1 cylinder is worse than the others. i have good compression on all cylinders. I just noticed that whistling noise yesterday I sprayed carb cleaner on everything no leaks has to be inside? I dont know what else the whitsling would be i put me ear the the intake and its coming from that area. well this winter i wanted to take it off and clean it up a bit so more reason to i guess. But even if it was sucking air on that cylinder it wouldnt make it so rich that just the one cylinder would foul out. just make a code 91 because of the extra air. And that should make all that side rich. I will check the rockers and see what i come up with.

Thanks
 

liljoe07

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#15
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Swap the 02s tomorrow and see what you get code wise.

Also, take a Test light unplug the #5 injector and hook a test light to the EFI harness connector. Just turn the key to on position. Test light should not be lit up.
 
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cheese_05_70

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  • Oct 16, 2009
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ok will do tonight thats the same thing i told myself last night that i needed to check tonight. I was just going to borrow a set of noid lights to check it tho. thanks
 
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cheese_05_70

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#17
  • Oct 17, 2009
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Used noid light tonight and injector is firing normally. not on when koeo but blinks when running. Didnt get time to check o2 will do tom. A family member have a stroke earlier this week so i havent had time. I guess i will try to check the rockers too see if one is slightly hanging open? i dont know y else that cylinder would be fouling.
 

HISSIN50

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After swapping O2's, I'd do a quick compression test (or leakdown test if you have the tool) on that cylinder before tearing into things. Teardowns create more variables.
 
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cheese_05_70

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what kinda tool you use for leakdown test do they make one you can rent? i know it puts compressed air in the cylinder. thanks
 

jrichker

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See the link in my sig to my web site . It has instructions on how to build your own blow down compression tester.
 
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