Author Topic: Did we ever figure out the "Hot Start Problem" (Read 89216 times)

gearheadE30 · « **Reply #45 on:** February 16, 2009, 08:12:07 AM »

just an interesting note: my car doesn't even have the mystery plug, and the harness is original so it wasn't removed. Build date 3/90 fwiw

AcSchnitzer318is · « **Reply #46 on:** February 16, 2009, 12:02:32 PM »

I'm also in for a sticky... this problem plagued TONS of ppl and it should be easily found by any new sufferers who just bought their 318is and are wondering why it does this.

Burnall4 · « **Reply #47 on:** February 16, 2009, 03:21:10 PM »

This thing hasn't been stickied yet?!? Hmmm maybe I should just delete my original post

Anyway, I have been driving my car for a while now and everything is great, except I figured out my AFM is crapping out. So, I guess I got to replace that. On another positive note, my gas mileage has increased, not leaps and bounds but it has. I was getting 290 to a full tank in the city, now I am getting 310-320. Anway. Now I just have to do some routine maintanence and out this car to work, ehehehe!

Birdman16 · « **Reply #48 on:** February 16, 2009, 07:54:57 PM »

To answer the question, I have acttually gotten about the same gas mileage... No problems or decreases whatsoever... Also, does thisbplig have to do something with the air fuel mixture on startup?? Because I had a fuel problem with the plug connected and now there is no black smoke on startup!!!

Secondly, I have found that with this disconnected wire... The car absolutely kicks the ass of modern bmw's with a bottle of Lucas oil octane booster and sunoco 93 pump gas!!! It's a little too fast... Secondly it pulls really good at low rpms... An yes I know it is bad for the clutch... There is no need to downshift as the car pulls like otbis a gear lower than what it really is!!!

Whooo!!!

e30nub · « **Reply #49 on:** February 16, 2009, 09:02:06 PM »

Still going smooth. This thread is the best thread evar.

waclawb · « **Reply #50 on:** February 21, 2009, 08:23:57 AM »

Wow, my problem is finally solved.

sports.racer · « **Reply #51 on:** February 24, 2009, 09:38:46 AM »

Quote from: keflaman;66549

Tthe other wiring manual (e30_91_modified_re_(2)) and see it on page 1360-4 as well.

Never mind, found the manual...

Nice stuff on that site you posted, thanks.

sports.racer · « **Reply #52 on:** February 24, 2009, 09:41:15 AM »

Quote from: Burnall4;66648

I was getting 290 to a full tank in the city, now I am getting 310-320. Anway.

Really? I'm lucky to get 250, I don't think my right foot is that heavy. What kind of range are others getting?

AcSchnitzer318is · « **Reply #53 on:** February 26, 2009, 01:40:23 AM »

I just got 330 with mixed city driving... worked out to just over 27mpg. This is after the "fix." Before disconnecting that wire I was getting 24-25mpg mixed city.

Meister · « **Reply #54 on:** February 26, 2009, 01:43:05 AM »

I think this has improved my gas milage also. Before i was getting around 290 mixed city/hwy. But my last full tank i got 315mi on mostly city.

sports.racer · « **Reply #55 on:** February 26, 2009, 10:24:48 AM »

Wow, my mileage is pretty low compared to yours. Maybe I need a new o2 sensor to start with, I'm sure it's never been replaced.

gearheadE30 · « **Reply #56 on:** February 26, 2009, 01:37:18 PM »

I get an average of 27 according to both my calculations and the OBC, and I don't have a plug. Were you guys' plugs just hanging out of the harness or did you have to unwrap it?

sports.racer · « **Reply #57 on:** February 26, 2009, 10:54:38 PM »

I got 21.5 on my last tank - going to have to fix this.

The evil wire in my car was fully exposed on top of the bundle. It looked like I had accidently pulled them which is why reconnectd them.

Meister · « **Reply #58 on:** March 05, 2009, 11:12:26 AM »

Quote from: gearheadE30;67280

I get an average of 27 according to both my calculations and the OBC, and I don't have a plug. Were you guys' plugs just hanging out of the harness or did you have to unwrap it?

Yea, mine was just right there out in the open.

odbod · « **Reply #59 on:** March 10, 2009, 02:35:26 AM »

I get upto 330 from a tank, mostly motorway miles, 2 runs a day to and from work ~18miles each way, so 2 cold starts a day, cruising at an indicated 85mph, but actually at 3800-3900rpm, so ~78-80mph in reality.
In US gallons (3.78litres) that's 27-28mpg (I think), in UK gallons (4.54litres) that's 33mpg.

I didn't have a lambda sensor as euro cars are non-cat versions, but I am converting to run on lpg so I've had 2 lambda bosses welded in, since then I've hooked up a new factory sensor and un-plugged the cable, it took about 3-4days to settle down (lumpy idle) with the sensor connected but now it pulls much better on part throttle, particularly at motorway speeds.

Also we run on minimum 95ron fuel in the UK and can get 97-98ron at every filling station so the tuning on the original ECU is setup for this which may help economy. The ECU is tuned for 95ron, so running 98 makes little difference to a car this age.

I haven't used a whole tank of fuel yet so I don't know if the fuel economy has increased, it looks like it may have done as the tank doesn't seem to be emptying itself as fast, but that may be wishful thinking...