1989 e30 Convertible stall, rough idle

[winhotel]

BMW e30 1989 Convertible Automatic

I've been searching all over the internet and I'm just running around in circles. Let me first tell you what was done to the car. I've pretty much rebuilt this whole thing.

1. Head / exhaust / intake gaskets replacement / cam seal / crank seal / Timing belt / Water Pump / Head job / Valve Adjustment

2. Spark plugs & wires

3. Distributor cap & rotor

4. Idle Control Valve

5. Crank Position Sensor, Coolant Temp Sensor, O2 Sensor

6. Main Relay, Fuel Pump Relay

7. Throttle position sensor, on the dot with ohm and correct calibration reading

8. Changed fuel regulator

9. Changed fuel filter

10. Test fuel pump, cleaned strainer

11. Test MAF

12. Changed and swapped ICV, test resistance on ICV *GOOD* (3 plug)

13. Checked alternator GOOD

14. Recharged car battery, test battery is GOOD, battery reading almost
14V when running, 12.6 when still.

15. Emptied gas tank, with new gas.

My problem started when the car would die at a stop light. I would have to press the accelerator to keep the RPM up.

At this point car only idles for about 5 minutes when cold start,
After it is warm, it will not hold the idle and RPMs will begin to fall. It goes up and down on it's own to try and stay alive, but it eventually dies.

I could hold on the gas, but if I let go it will immediately die when warm.

Really thirsty to get this fix, any help will be great. Getting a 1222 stomp code.

Thank you.

[cspec]

1222 is faulty oxygen sensors I think

[winhotel]

1221 is O2 sensor

"1222" fault code seems to indicate that the Motronic is recieving a signal that indicates the air/fuel mixture is excessively rich, or excessively lean, for a period longer than 10 seconds.

But, I can't seem to find how or what is making this happen.

[cspec]

Have you replaced the hoses? Leakdown test to check for leaks?

[jeffnhiscars]

1221 is O2 sensor

"1222" fault code seems to indicate that the Motronic is recieving a signal that indicates the air/fuel mixture is excessively rich, or excessively lean, for a period longer than 10 seconds.

But, I can't seem to find how or what is making this happen.

I think that's a lambda fault aka o2 sensor. Recheck your valve clearances and did you ohm the tps w a 3mm feeler gauge holding the butterfly open ?

[winhotel]

Have you replaced the hoses? Leakdown test to check for leaks?

So, I did a leak down test. Multiple times because I really wanted to make sure my reading were right.

I used a balloon to know the air was coming up to figure out where TDC and compression was for each cylinder. I pumped 20 PSI and stuck in it 100% leak. I stuck in 80 PSI about 90% leak on all cylinders.

1. Throttle body open - no noise
2. Exhaust at the rear of car - no noise
3. I have no bubbles in the radiator, as I had recently changed the head gasket. The car was working for about 100 miles before all this even happened.
4. Dip stick - VERY OBVIOUS hissing sound

I just want to make sure that on these M20B25 engines there as anything special I had to do for this test. If not, yes I am having 90% - 100% on these cylinder, all sounds coming from the oil dip stick.
The park plugs are charcoal black, and so is the O2 sensor, but they can easily be wiped off, so it's no like crazy carbon built up.

Is this it? Is this the answer? my rings are screwed?! The car does have 265,000 miles on it, and engine block has never had anything done to it.

What else should I look out for? Any other tests to make sure its the rings before I pull out the engine and rebuild?

[winhotel]

yea guys, I've been diagnosing this thing for like almost 2 weeks. Almost everything has been replaced.

Oil filler cap is good. I checked the EVAC valve.

Here's what I'm getting for dry compression test. All spark plugs out, fuel relay out. throttle all the way down
Cylinder 1: 150
Cylinder 2: 150
Cylinder 3: 150
Cylinder 4: 165
Cylinder 5: 155
Cylinder 6: 100

They didn't seem to pop up immediately to the max point, it takes about 3 revolution until they reach those numbers

I did a wet test on Cylinder 6 and it went to 105

Also note that leak down test at 80-100 PSI shows extreme leak, 90%-100% on all cylinders. Intake valve no hiss, exhaust pipe no hiss, radiator cap no bubbles or noise, hiss can be heard from oil dip stick when open, and also can be heard when oil fill cap is open straight from the top of the head, but that might be the hiss that is going down into the oil pan and coming out of the dip stick. Unless it's leaking somewhere else?

Is this sounding like a piston ring problem? All the pistons? oh man. I just want to make sure before we pull out the whole engine. Planning on doing it this Sunday and making a youtube video.

[cspec]

Sounds like you need a new head man... Sounds like bent valves to me

[winhotel]

My head was just redone. Head job and all before all this started happening. It's been driven for about 50 miles until this problem became worse and worse. The car would not idle at stop lights and stall. Now it will only idle at park for about 5 minutes and begin to hesitate, trying to grasp for air, holding onto dear life, and then dies. Once the car is warm, it's impossible for it to idle for 5 minutes, it will die in a matter of seconds.

Then a bunch of things were checked out and replaced, including all the things mentioned above.

[mazzo]

Did you check the intake boot and hoses for leak and crack? Looks like an air leak to me.... done any smoke test on your car before?
I see you mention MAF - so your are using Miller? Or just a typo and you are using AFM? If AFM, how did you test it?

[Blacke30vert]

i had similar issue last year and after tearing my motor apart i found out it was the icv. ordered it on eBay and its been fine since, other then cooling issues lol

[fporro]

my 153 ecu went bad gradually, it would make car sputter at certain rpm's upgraded to a 173 and all is well., there's other versions but the 173 seems better