Hi everybody,

This is my first post to the forum. My B2 is a pretty standard 1984 model with 2.8 V6 and manual everything. I love it to death! It runs pretty poorly (long starts, little power at low rpms, stalls) but at least it gets around

It just failed emissions, so I do have some data. Its off the charts in hydrocarbons and CO. The expert there said the engine is running rich. I can definitely believe that too considering the way it runs, and the crummy mileage.

I just tried pulling the codes, but I am not getting any readings back. I tried the tech article for EEC-IV codes, and I'm a wiring whiz so I know I am doing it right. Only thing different is I'm using a 12V test lamp instead of a analog voltmeter, I only have a digital voltmeter.

First I connected the lamp to the +12V battery post and test output pin with the engine off. The lamp glowed continuously.

Next I turned the key to the on position. The lamp went out for three seconds then glowed continuously.

Then I jumpered the two pins to start the test. I heard a click down below like a relay or something. But the lamp did not change, it just glowed continuously.

I repeated this process a few times, with the same results. Is it possible that my computer is fried? Will the engine run without a computer? Is now a good time to consider the duraspark conversion? That project actually sounds pretty cool. It will still fail emissions, but in Oregon cars over 20 years old don't have to test for emissions, which is next year for this beast!

Any advice would be appreciated. Thanks!

 

Try the test again, with this little twist: Hook up your jumper wire before turning the key on. the test starts when you turn the key on.

 

Welcome to FTE!!!

 

Thanks mrshorty that was it!

Here are my codes returned:

KOEO
21 - engine coolant temperature sensor ECT out of range
24 - intake air temperature sensor IAT out of range
31 - EGR circuit below min volt
63 - throttle position sensor TPS circuit below min volt

CM
31 - EGR circuit below min volt
41 - No HO2S11 switch detected
63 - throttle position sensor TPS circuit below min volt

KOER
12 - No hi RPM control
23 - TPS out of range
25 - knock not sensed *
31 - EGR circuit below min volt
35 - EGR circuit above max volt
41 - No HO2S11 switch detected
58 - Idle air control circuit failure
73 - TPS chagne insufficient *

I ran the KOER test 4 times. I had trouble getting a good goose, it likes to knock and stall if I goose it too hard. I got code-25 2 times, and code-73 3 times. All other codes were consistent.

That's quite a grab bag of codes!! Where do you guys think I should I begin? Carberetor was shop rebuilt not long ago, so it should be okay mechanically. All other parts are questionable.

 

usually, the best place to begin is the KOEO codes.

KOEO 21 & 24 are commonly set by running the test on a cold engine. Repeat the KOEO test after running the engine to operating temperature. If you know the engine was warm, or you repeat the test on a known warm engine and these codes are still there, read on.

KOEO 31 note that a KOEO code almost has to be an electrical fault rather than a mechanical fault, because the engine isn't running. I'm not familiar with the 2.8, but be sure to check the electrical components (wires, EGR sensor, etc.) until you find what's wrong. If you don't yet have a wiring diagram, that's probably the first thing to do.

KOEO 63 Not a common code, but it indicates a fault in the TPS circuit.

An interesting note for all of these codes, all of those sensors (at least, I expect the EGR sensor ison the 2.8 as it is on the 2.9) powered by the computer's Vref circuit. Especially if the 21 and 24 turn out to be real codes, I would probably start by checking Vref. Again, if you don't yet have a wiring diagram, get one.

 

Mrshorty you are correct again, I did the engine off test cold. I will try again tomorrow afternoon and post the new codes.

 

Ok, I did the KOEO test with a warm motor:

31 - EGR circuit below min volt

Only one code this time, that's an improvement I have the Haynes manual which has some wiring diagrams, but I am not seeing any EGR components. Can I get this diagram online?

Thanks,
tim

 

The vehicle repair guides at www.autozone.com have wiring diagrams. They seem to be adequate for basic work. Check them out and see what you come up with.

 

Thanks for the link Mrshorty, I will snoop around the EGR electricals this weekend and let you guys know what I find.