Schwarz/Houndstooth Mtech1 S52 coupe: 10 year journey

[Habla]

1. Hmm, so a fault with any sensor can cause a limp mode effect? I guess I'll check those things for spec.

3. Spacers on top of the rack. It looks like I have equal toe in. It feels terrible haha.

5. What do you do with the hose that goes to the tank then? And then get the resistor piece to stop codes from the evap valve?

[e30austin]

1. Hmm, so a fault with any sensor can cause a limp mode effect? I guess I'll check those things for spec.

3. Spacers on top of the rack. It looks like I have equal toe in. It feels terrible haha.

5. What do you do with the hose that goes to the tank then? And then get the resistor piece to stop codes from the evap valve?

Pretty much. Did you replace any of them? CTS is $20, 02 is $80, knocks are $50 a piece. Would be a good place to start.

I set the toe all the way in on my M3 rack in the red car. Never took it in for an alignment. Guess it doesn't matter now. Lol

Plug the hose that goes to the tank and leave that little sensor for the charcoal canister plugged in if you don't want a check engine light. I never had a working one when I had either motor in my car, so it didn't really matter to me. Maybe the bulb is burned out.....lol

[Habla]

I didn't replace any of the sensors. I'll start with the knock sensors, because those looked pretty old.

I might get rid of the canister later if I swap to a late model fuel pump, but my fuel filter is in the engine bay anyway, so I just mounted them side by side.

[Habla]

Long-needed update:

Finally got some work done on the car, trying to sort out all the problems. Good news and bad news:

I was able to fix the exhaust leak and correct operating temp with a lower tstat and fan switch.

I installed new Bosch knock sensors and an o2 sensor hoping it would fix the 3500rpm cut, but it didn't.

• The engine ran fine for 20 minutes, but then the issue came back again and there is NO CEL now!? Did a stomp test anyway, and it spits nothing.
• I have tested the crank sensor, and it ohmed at ~520Ω.
• I don't know a test for the cam sensor, but I have a spare that seems newish that I can throw on.
• I'm going to replace the ECU temp sensor soon, since it is relatively cheap...
• I want to try another ECU, to see if that is the issue.
• I have yet to check fuel pressure. It could be a lack of adequate pressure at higher rpm?
• Clogged cat/exhaust system is another possibility. How do I check that?

I would LOVE to get this shit sorted.

-P

[Habla]

Bittersweet update!

Hmm what's this?



An 86/87 euro valance with complete fogs!



Snip snip, spray spray



Got euro?



Installed! Still need the lip though.




Then the heater core fails, puking coolant all over the carpet. On the freeway. Then the motherfucking tow truck driver cracks one of the foglights I JUST put on!

Swell.



On the bright side, there is no rust in the floor!



Still working on that project...


This may turn out to be unimportant, but I noticed that I forgot the injector harness ground wire when I installed new sensors a few weeks ago. I just left it hanging there. I reinstalled that asap. So after I did all those sensors, the CEL went away, and no codes come up, but the car would still hesitate at 3500. Hoping that this ground wire is part of it. I won't know until I fix the heater core though...

There's always something!
-P

[george graves]

Valve cover looks amazing! Can you over cook it?

[Habla]

Its easy to cook it too much,I almost did. And don't tell the gf that I used the oven!

[e30austin]

That injector wire is the main DME ground. It needs to be connected.

[Habla]

Yeah, I know. I'm surprised the car ran at all with it dangling in the air.

[e30austin]

Me too honestly.

[Habla]

Update!

This round of replacement parts:
-Fpr vacuum line was old & brittle, so there wasn't enough vacuum to maintain proper fuel pressure.
-Large & small ccv breather hoses were very pliable, and the small one was pinched.
-Intake boot was cracked.
-Replaced plugs with Bosch coppers, instead of platinum +4s

Results: SOLVED! I can mash it now, so happy! No codes, no hesitation.

Theory: vacuum leaks and poor fuel pressure caused lean condition and a knock, which was reported to the DME, which inflicted limp mode.

[TimeMachinE30]

Great work.

[Habla]

Thanks. Turned out to be a relatively simple fix, but it took a while to figure it out...

[Habla]

Looks like I spoke too soon. Same issue came back.

[Habla]

So I decided to install the spare cam and crank sensors I have.

This is what the cam sensor looked like. It wasn't obvious upon inspection, it was caked over. It is badly frayed, I can see wire. Glad I'm changing this one!



And the crank sensor was separating at both ends like this.



Resetting the car now, pretty confident that these will improve the situation!