Running Rich/misfiring

[jbraswell]

So.. I had a TCD intake on my car for about 4 days. It was nice, sounded good, ran great, but it had a cheap autozone filter on it, which was pretty dirty now that I look at it. Well, night before last, I turned on my car and it was having trouble starting. It finally started and ran extremely rough (sounded like a tractor), and it was running extremely rich. I let it run for about 20 minutes and the idle smoothed out, although still surging a little. After letting it warm up I tried to drive it around a little bit and it was misfiring pretty badly. I took off the intake, put the stock air box back on, checked all of the intake boots and everything looks fine. It seems to run worse now though, it misfires like until it warms up for about 20 minutes, and then it still does not run right (runs rich and is down on power). Im thinking something got into the intake, Im about to go check the current on the air flow sensor right now.. Any other suggestions?

[ThoreauHD]

You bought gas with ethanol.

[jbraswell]

well i changed out the afm...nothing, checked the resistance on the idle control valve: 22 ohms, 24 ohms and 45 across all 4. Took it for a drive, and again it ran relativley normal after it was warmed up, but it did feel a litle down on power and was still running rich. But as soon as I turned it off and tried to crank it again, it was running rough and blowing black smoke

[ThoreauHD]

Err.. and no engine codes eh. If you're sure it's rich and not crap gas, then the next would be to check for a failing 02 sensor.

[jbraswell]

check engine light comes on after a few minutes at idle, but goes away with throttle. I dont have a code reader.

I always put premium in it because it has a chip.

[ThoreauHD]

http://www.peachtreebmwcca.org/ptLocalShops.asp

Take it to a local shop and have it read. Or join your bmw cca chapter and borrow the tool.

[genphreak]

So.. I had a TCD intake on my car for about 4 days. It was nice, sounded good, ran great, but it had a cheap autozone filter on it, which was pretty dirty now that I look at it. Well, night before last, I turned on my car and it was having trouble starting. It finally started and ran extremely rough (sounded like a tractor), and it was running extremely rich. I let it run for about 20 minutes and the idle smoothed out, although still surging a little. After letting it warm up I tried to drive it around a little bit and it was misfiring pretty badly. I took off the intake, put the stock air box back on, checked all of the intake boots and everything looks fine. It seems to run worse now though, it misfires like until it warms up for about 20 minutes, and then it still does not run right (runs rich and is down on power). Im thinking something got into the intake, Im about to go check the current on the air flow sensor right now.. Any other suggestions?

I doubt it is the intake itself. More likely that you have upset one of the wires on the AFM harness or now have an air-intake leak- unmetered air will upset your motor (and ECU) a lot. Be careful of overtightening your AFM and Throttle Body boot faces- as well as not sealing them right- they should be perfectly round (too much pressure will crush them or oval them- eiother is hardly good and will cause a leak). Perhaps the TB boot is broken or cracked after the messing around. A test might be necessary. I'd check those connections, and check your plugs are ok. Ethanol (at up to 10%) doesn't affect my car at all. It might be your O2 sensor, or temp sensors. Check them, and your coolant level. Nick

[jbraswell]

Took it to my indy to get the code read.. coolant temp sensor and o2 sensor were both bad. Replaced those and it was still backfiring through the intake and running very rich. Finally, my mechanic pulled the vacuum line off the fpr and it was full of fuel, which means the intake was pulling fuel. The diaphragm inside the fpr was cracked. So, new coolant sensor, new o2 sensor and new fuel pressure regulator and Im back on the road.

p.s while all this was going on I decided to smoke my tail lights. I work at a dealership/bodyshop, so I paid my buddy the painter $20 and we just mixed a little black in with some 3M speed clear, reduced it and they turned out GREAT. I was very suprised with the result, I'll post some pics tomorrow