7th Annual East E30 Picnic - July 15 2023

[McGyver]

Me neither. My dumb rich running issue came back. Instead of being at the picnic, car will be in the shop. Have a good time those who can attend!

Check engine light, drivability issues, or just smells funny?

[ZeKahr]

Check engine light, drivability issues, or just smells funny?

All of the above. Getting the 1222 code (mainly happens below 1500 RPM). Plug tips are black and the exhaust has a tiny bit of black smoke. Threw new spark plugs and O2 sensor + sanded cap/rotor leads and it ran fine for like a week before the symptoms showed up again. Also the idle is bouncing between 500-1000 RPM when fully warm. Had a shop smoke test and they said VCG has a huge air leak (even though it’s a brand new VCG). Tightened the VCG bolts and no dice. Could be a bunch of other things.

[rmdashrf]

I am an hour and 45 minutes away, I might check this out. Its kind of a small park, wondering how that works out. . .

[McGyver]

All of the above. Getting the 1222 code (mainly happens below 1500 RPM). Plug tips are black and the exhaust has a tiny bit of black smoke. Threw new spark plugs and O2 sensor + sanded cap/rotor leads and it ran fine for like a week before the symptoms showed up again. Also the idle is bouncing between 500-1000 RPM when fully warm. Had a shop smoke test and they said VCG has a huge air leak (even though it’s a brand new VCG). Tightened the VCG bolts and no dice. Could be a bunch of other things.

For the VCG, did they smoke test it to figure out where it's leaking? (Rocker shaft plugs, cam shaft seal, gasket itself, breather tube, etc.) Have you tried replacing the engine coolant temp sensor (blue plug) with a good Bosch sensor?

[ZeKahr]

For the VCG, did they smoke test it to figure out where it's leaking? (Rocker shaft plugs, cam shaft seal, gasket itself, breather tube, etc.) Have you tried replacing the engine coolant temp sensor (blue plug) with a good Bosch sensor?

They said it was from the back of the valve cover gasket. The valve cover gasket is literally brand new. I didn’t replace the coolant temp sensor but I did check its resistance at 20C (came out to 2200 ohms) and with the engine fully warmed up (this one was odd; it came out to 208-213 ohms - my intuition is a worn CTS should have higher resistance than what the Bentley states). I unplugged the temp sensor and the engine ran worse.

I also just cleaned the temp sensor on the AFM, lubricated the barn door inside the sensor, and strangely enough all of the symptoms disappeared, except for the low idle (750 engine stone cold, 500 fully warm). Still gonna have a shop look at it - I have a feeling this rich running issue is gonna return lol. This shop specializes in E30s (one of the guys there owns a red turbo iX and the other one has an S52 swapped M3 I think).

[MrBurgundy]

Damn, that sucks.. it could be the FPR?

Below 1500 rpm, the vacuum generated higher than anything beyond that, so if the FPR diaphragm is busted, it could be pulling it into the intake via the vacuum hose on the rear of the intake.

[ZeKahr]

Damn, that sucks.. it could be the FPR?

Below 1500 rpm, the vacuum generated higher than anything beyond that, so if the FPR diaphragm is busted, it could be pulling it into the intake via the vacuum hose on the rear of the intake.

Don’t think it’s the FPR, I pulled the hose (on both the manifold and FPR ends) and no fuel came out of either end). FPR also looks brand new

[McGyver]

They said it was from the back of the valve cover gasket. The valve cover gasket is literally brand new.

But did you also change the rocker shaft plugs? You can put them in dry, but I like to put a SMALL dab of sealant on the top corners where the plug meets the head casting. Also, I don't see how you could have a bad enough leak to cause a real problem.

I didn’t replace the coolant temp sensor but I did check its resistance at 20C (came out to 2200 ohms) and with the engine fully warmed up (this one was odd; it came out to 208-213 ohms - my intuition is a worn CTS should have higher resistance than what the Bentley states). I unplugged the temp sensor and the engine ran worse.

I'm not sure what the failure mode would be, but the CTS is very important to the correct functioning of the engine. It would call for warmup enrichment and dictate whether the engine runs in open or closed loop.

Maybe you need to unplug the DME for a while to clear adaptations from a bad O2 sensor or whatever. My car is having some surging issues at idle and the Check Engine sometimes comes one when cruising at a constant speed. I threw an O2 sensor at it and plan to just drive anyway. Maybe it'll be better, maybe it'll run like shit. Either way, I'm not worried about making it there and back.

[ZeKahr]

But did you also change the rocker shaft plugs? You can put them in dry, but I like to put a SMALL dab of sealant on the top corners where the plug meets the head casting. Also, I don't see how you could have a bad enough leak to cause a real problem.

Shop did the VCG along with some other work I had them do like 3 months ago, not sure if they changed the shaft plugs. I’ll ask them about it when they call me to let me know what’s up with my car. I left my maintenance records in the glovebox so don’t have access to them right now.

I'm not sure what the failure mode would be, but the CTS is very important to the correct functioning of the engine. It would call for warmup enrichment and dictate whether the engine runs in open or closed loop.

Yeah me neither. I’m thinking the low CTS resistance might be causing a low hot idle symptom. I know on the older M10 and 325e cars the idle speed control unit is fed the CTS voltage/resistance as an input, and that the idle speed goes down as the sensor resistance goes down. I have a feeling this logic was carried over into Motronic 1.3.

Maybe you need to unplug the DME for a while to clear adaptations from a bad O2 sensor or whatever. My car is having some surging issues at idle and the Check Engine sometimes comes one when cruising at a constant speed. I threw an O2 sensor at it and plan to just drive anyway. Maybe it'll be better, maybe it'll run like shit. Either way, I'm not worried about making it there and back.

Already did that, car ran fine for a while but symptoms showed up again. I threw in a brand new Bosch O2 sensor too.

My car has also intermittently flashed the CEL during cruising, but it’s pretty rare. If your car is idle surging, there’s a good chance you’ve got a vacuum leak somewhere.

I’m just hoping these issues aren’t caused by a 35 year old engine harness. The wiring in these cars is getting pretty old and there’s a 99% chance it hasn’t been replaced by any of the POs

I’d like to get my issues addressed before I drive over there. If my car’s not ready by Friday, I’ll see if I can borrow my parents car and come thru to check out the other E30s

[ZeKahr]

So some good news - shop found out what was wrong with my car - AFM wasn’t calibrated properly, causing the car to run rich. After setting it correctly, the car runs a lot smoother and quieter and pulls better up hills. Still idles at 500 fully warm. Anywho, I’ll bring it out tomorrow

[Panici]

Everyone, post some pictures of the event!

[McGyver]

No particular order, and I forgot to take pictures of the turbo LS hill climb car. I think the owner said its ~600-700 hp/tq

The person with the longest drive got a sick m-technic fabric bag from ninestitch. There were at least 5 cars with ninstich interiors, just amazing.











[img]https://i.imgur.com/4aeyp97h.jpeg/[img]

[Aleman]

Thanks for the pics! I had fully intended to go this year, but family stuff...
Anybody have more pics to share?

[ZeKahr]

I was too busy staring at the cars to take pics. Maybe next time

[D3R3K]