CEL problems after replacing tranny

[Peter Westling]

Hi all,
I did a tranny replace last weekend. Everything went sort of ok...
Car has about 130k miles...

The gasket between tailhousing and the tranny is leaking a little, not a huge problem, will replace that soon...

Anyway, after filling up atf and testdrive the CEL goes on after some minutes, stays on for a minute or so and then stops for a minute then it goes on again...sort of cyclic

The exhaust smells much, snow on the ground became black from the exhaust quickly... I would say it runs rich...

I miss out some power, the shiftpoints arent the same as with the original A4LD, now its has to rpm some more to shift..

I pulled the codes:
KOEO:
73 - I guess this is ok since I did give any throttle during the test
77 - same with this, no throttle during test phase...
88 - Not in haynes... found some other info about this code relating to throttle kicker solenoid, choke, Fan curcuit, A4LD converter clutch override solenoid or something with the ignition system

KOER:
538 System did not receive "goose" test
137 O2 sensor rich left
173 O2 sensor rich right

I assume my car runs in limp mode or something, maybe that affects the shiftpoints..?

Since I did not remove th y-pipe and the O2 sensors were still in place when we with some cursing, struggling and fortune got the old tranny out and the new one in we might "disturbed" those? Did I destroy both of them???

Is there somebody that could chime in with a point of direction here?

FPR? O2 sensors?


regards

 

[savagefan]

First, check to see that you're not sucking atf thru the modulator valve. Adjust TV cable check all connections thoroughly. Was the trans from the same year vehicle?

 

[Glacier991]

This does not sound like a transmission problem, but more like a fuel system problem. Your suspicion regarding the 02 sensors is a valid one IMHO. Shift points can be affected by several things, and the modulator is top of that list...

 

[Peter Westling]

Savage, thanks for the reply.
The new one was stamped 94. So I upgraded a year...
I have checked the vaccum hose, both eletrical, kickdown and shiftlinkage and it seems to work ok. I went out and doublechecked them now and the connector from the O2's..
How can I check modulator valve that you mentioned?

 

[Glacier991]

Pull the hose from the modulator and check for the presence of fluid is the easiest check... you can hook up a vacuum pump to it and see if it holds vacuum is the more sophisticated test.

 

[Peter Westling]

Glacier, thanks for the replies!
I assume that the modulator is same as vaccum diafragm..? As seen in this nice photoalbum:

I went out to see if there were any atf in the hose but no, it was dry...

Is there something I should think of when replacing, I assume this tranny has been on a shelf for some year or two, should I retension bands or so?

 

[savagefan]

Yes that's the baby, try hooking up a vacuum pump to the valve or if no-one is looking hook a hose up and suck on it to see if it holds a vacuum. Band adjustment can't hurt quite straightforward lotsa help on this site. Did you adjust your TV cable?

 

[Peter Westling]

Savagefan: Oh, the tv cable.. Hmm I am afraind that you misunderstand me now, when I was talking about the shiftpoints it was not related to the shiftlinkage or levers.. It was more from 1-2-3-4 downshift used to be around 1500 rpm, it is the same now, upshift used to be around 2000rpm now it is approx around 2500.

I will try getting a vaccum pump to see if the modulator works..

What about the Codes, any suggestions there?

 

[MrShorty]

comments on codes:

KOEO: should be getting three digit codes instead of 2 digit codes here (just like in the KOER test. Double check to make sure you interpreted the test correctly.

KOER:
538 almost always means you neglected the goose test.
137/173: Computer couldn't get a lean signal from the O2 sensor. Could be a lot of things, and one has to suspect KOER results until you get a pass (111) from the KOEO test. You already mentioned the FPR as a possible problem, have you checked fuel pressure? checked for a bad FPR diaphragm?

 

[Peter Westling]

MrShorty, I appreciate the answer:
I dunno why but I thought "1" was a separator between the codes... I redid the KOEO and got this:
Fastcodes.....116....114....116....114..........
1.....173..177..179..188.(repeated).173..177..179..188

I have rechecked the vaccumhose on the tranny, and also followed it to the vaccumtree. I found no atf in the modulator hose.
I inspected the O2 sensor lines and on the left one I noticed a small dent on the cable, it seems that only the plastic shield is damaged and the origin of it CAN be when we twisted and turned the tranny into place, there is a kind of sharp edge on the left side (the part where the firewall begins) photo illustrates the dent.

If one sensor is down does it affect the other one? I see it as really unbelievable that both of them is gone at the same time, but what do I know...

 

[MrShorty]

KOEO 116 & 114: These are almost always a result of performing the KOEO test when the engine is cold. Be sure to perform the test on a warm engine.

CM 173/177/179/188: Essentially all mean the same thing. At some point in the past, the O2 sensor read rich and the computer couldn't correct the condition. O2 sensor codes can be among the more difficult to diagnose. Start with a few basic questions:

1) Perform KOER test (previously warmed up engine) and see what you get. It is often easier to diagnose from the KOER test, because KOER codes represent real time "hard" faults.
2) Is the engine running rich or lean? One important thing to realize is that the computer can't tell when the O2 sensor is reporting truth or error. You don't want to shoot the messenger just because he delivers bad news. If the engine is really running rich as the O2 sensor claims, then investigate why the engine is running rich (Fuel pressure too high, FPR leaking into intake, etc.). If the engine is really running lean, contrary to what the O2 sensor is reporting, then investigate why the O2 sensor is in error (bad sensor, short to power, etc.).

 

[Peter Westling]

1) I have done the KOER test already, as seen in my first post:
(When I performed that one the engine was warm, it was just when I redone the test yesterday it was cold when doing the KOEO)
KOER:
538 System did not receive "goose" test
137 O2 sensor rich left
173 O2 sensor rich right

2) The exhaust smells much, snow on the ground became black from the exhaust quickly... Never done that before. I would say it runs rich...

Still I have to believe this is related to the tranny replace, since I had to struggle with the top bolts on the bellhouse I might damaged the cabling there...? Maybe I should measure to see that I didnt break anything?

I really dont know what next steps I should take... testing the FPR?

 

[Maniak]

To check the FPR just get a Fuel pressure tester.. I got one for <$40 from autozone.. If its bad, you will see high pressure.. It should be <40psi..

~Mark

 

[Peter Westling]

Actually I got a good price for a new one and I will replace it hopefully today.
If that does not work I'll go on and do the O2 sensors too. Sooner or later they'll break... I would say with 130k miles it is time to replace.....

 

[tonyd12345]

cel

I almost completely destroyed my O2 sensor replacing my tranny. I just drove it with the cel on anyway. I did see some decrease in fuel mileage, though.

 

[Peter Westling]

I cleaned the MAF sensor, Replaced the FPR, cleaned my KKM and relearned the EEC..
(welcome to the acronym heaven!)

I drove it for a bit, response was WAY better, the fumes from the exhaust do not smell like poo anymore.

Since it is like -10c (50 F) and clock is near midnight I did not drive it to see if the CEL goes on again... Dont want to get stranded... I will take try it out tomorrow on the way to my work. But it sure do look promising. I'll get back with the status...

UPDATED:
The CEL did not go on today, the problem seems to be solved, broken FPR.
Thank's to all involved. I really appreciated the help in this issue!