Author Topic: My 91 BMW 318is repair log (Read 10395 times)

keflaman · « **Reply #15 on:** March 07, 2012, 10:34:48 AM »

Think it might be temperature related?

I had a problem with a '96 Chrysler LHS that wouldn't shift out of first gear. I tore that car apart and reassembled several times. I couldn't figure out what I was doing right to get the car running properly at the end of the day, only to run into the same problem the next morning.

The mystery solved itself one morning after coming back from a test drive and it wouldn't up-shift. I left it sitting in my driveway with the hood up while I rummaged through the factory manual for the hundredth time. Frustrated, I went back out and took it for another test drive and it shifted fine although I hadn't done anything to it.

I mulled it over in my mind trying to figure out what I had done differently and all I could come up with was leaving the hood open...which placed the transmission control module in direct line with the sun.:confused:

I pulled the TCM real quick and threw it in the fridge. When re-installed the car wouldn't shift. Put a heat gun on the TCM for a minute or two and it shifted. Ordered and installed a good used TCM and never had another problem with it.

keflaman · « **Reply #16 on:** March 07, 2012, 10:40:19 AM »

Quote from: DesktopDave;110851

It's more of a hot start problem...but it's worth checking out. Thread is here.

There's a CO potentiometer in the AFM that's enabled in non-cat Euro models (it's a lot like the old LH-Jet setup). Accidentally connecting that wire on "green" O2/catalyzed cars makes them run poorly.

Yup. More than one person has bought a non/poor running car and found this to be the solution.

Wrench · « **Reply #17 on:** March 07, 2012, 11:19:03 AM »

Thanks guys I'll check that out.
After about an hour and a half of idling, it died. It restarts and revs, but it misses a little and it won't idle, I checked the ECU and it was hot enough to fry an egg! Well, not THAT hot but REALLY hot! It's in the freezer cooling down while I eat lunch. I'll install it later and see what happens.
My coils measure 0.3 ohms primary.
I have coils on the way...

jrobie79 · « **Reply #18 on:** March 09, 2012, 09:24:39 AM »

I think I have the same problem, I can drive it though, but once it warms up I can't get on the gas....to pass on the highway, entry ramps, etc.... I replaced TPS with known working one, unplugged o2 sensor, no dice....

I'm going to measure the resistance on my crank and cam sensors, then the coolant temp sensor and see what i get from there. maybe I will replace the DME too, my sister has the same car and hers runs fine

longms · « **Reply #19 on:** March 09, 2012, 01:10:54 PM »

I hope the above mentioned fixes your issue but I had an issue like this a few years back and I ended up replacing the Crank Position Sensor and this fixed my issue. I had a bit of an oil leak that, over time, found a way to ruin the sensor. Might be worth checking out. Mine would rev to about 2,500 - 3,000 rpm and would feel like it hit a wall.

Good luck

Wrench · « **Reply #20 on:** March 09, 2012, 01:58:10 PM »

I'll have to replace the crank position sensor then... what the hec... I've replaced nearly everything.

Thanks!

jrobie79 · « **Reply #21 on:** March 09, 2012, 02:23:38 PM »

on my old m42 my crank sensor went and it wouldnt even start....I'm starting to think thats the culprit.

Wrench I've heard you should probably go with OEM as the other aftermarket ones might not have the correct resistance spec.

Wrench · « **Reply #22 on:** March 10, 2012, 08:28:56 AM »

Crank sensor ordered, due to arrive on Monday.

jrobie79 · « **Reply #23 on:** March 10, 2012, 04:16:34 PM »

where'd you get it?

Wrench · « **Reply #24 on:** March 10, 2012, 04:22:13 PM »

At work trough WorldPac, with a price break.

Wrenchin has it fringe benefits.

longms · « **Reply #25 on:** March 11, 2012, 08:37:37 PM »

Quote from: Wrench;110953

Crank sensor ordered, due to arrive on Monday.

Hope this fixes your problem.

Mine wasn't completely gone and would cut out at around 3,000 rpm but once it died completely the car was dead in the water.

Good luck

Wrench · « **Reply #26 on:** March 12, 2012, 04:03:24 PM »

Zoom zoom... fixed! The new crank position sensor did the trick. I ended up replacing some things I didn't really need to, but with my discount I didn't hesitate to just replace things. It's good to have it back to a baseline of everything new and or tested.

New coils should be here tomorrow and that's the last of it for the engine management portion.

Now to get at that loose suspension. Needs lower control arms and bushings.

Thanks for the feedback everyone.

DesktopDave · « **Reply #27 on:** March 12, 2012, 05:05:23 PM »

Sweet!

Thanks for posting the fix...once you get the suspension set up right that car will run like she's brand new!

Wrench · « **Reply #28 on:** March 12, 2012, 06:29:17 PM »

Yep... not much left to replace.

The new sensor was a better fit. The other one was NOT the right part! The wire exited the sensor directly towards the v-belt. It had been pulled back towards the sensor and wire tied there, very close to the v-belt. The sharp bend, lots of heat and seven years of wear (I have records of the repair by a local shop) and I'm guessing that it's intermittently shorting out at the bend in the wires. It measured 530 ohms. The new one also has the correct right angle plug at the junction box end.
She (Rosie) fired right up and ran, test drove great! Lots of pull left in this engine, even with diluted crappy gas it showed plenty of guts up above 4K. It should get better after a can of Seafoam and a couple tanks of high octane fuel have been run through it, at which point, I'll swap out the fuel filter.

Just to recap what's been replaced with a new part. What a journey...

Fuel Pump
Air flow meter
Main Relay
ECU
Breather hoses
Plastic water pipe and hoses
TPS
Cam Sensor
O2 sensor
Temp sensor
Fuel injectors (Bosch 4 hole)
Crank Sensor
Replace Coils (pending)
Lower left control arm (right one gets done soon)
Both control arm bushings

Oil looks good/fresh for now. I'll change it soon.

Saturday it gets four new tires and a state inspection. Then a trip to DMV for new plates then...
DRIVE IT!:D

Wrench · « **Reply #29 on:** March 13, 2012, 06:32:29 PM »

Suspension is all well now. No big surprises under neath. Brakes are OK, exhaust is in great shape. Minor oil leaks to track down. Gotta do that oil pan drop and search for bolts.

Can't believe how alive this engine is. It pulls well into 7K with ease. I ran it up through three gears but at 70 the front left wheel was shaking servery. It's BADLY worn and WAY out of balance.

Can't wait to get this thing shoed, plated and take a shake down cruise in it.