Hi,
I have a 1988 735i with an automatic transmission. I love the car and would be very sad to part with it. I have the following strange problem.

From a fresh start with the car in "E" (economy) mode, I shift to drive and being to accelerate. At this point, everything is normal. The dash indicates E D (so it's not a selector/neutral safety switch problem) and the car definitely feels like it's in first. However, after going up through about 2500rpm it's clear the car is not going to shift normally to 2nd. At about 3500rpm, the car realizes something is wrong and immediately goes into limp mode by shifting into 3rd where it stays until I turn off the car to clear limp mode.

I can drive the car in "M" (manual) mode using the shift selector for 1st, 2nd, and 3rd gear so the mechanics of the transmission appear to be fine. I just wish the car would shift into 4th when I put it in M D (I burn quite a bit of fuel in 3rd on the hiway).

I did a search on these forums for a similar problem and found the 750i EML light issue (more here: http://bmwe32.masscom.net/johan/eml_bulb/eml_bulb.html). This is very intersting to me as I noticed my EML light does not flash on when I turn the car on even though I can see where the light should be. As far as I can tell, my 735i should have an EML. Is there a solid way to determine this?

I also tried pulling the stomp codes from the car but it doesn't seem to respond. It's unclear to me if the 88s have this ability (Bently says yes, other places say no).

I took the car to the best ZF shop in the Bay Area (Peter Schmidt) and had them take a quick look at it. The first thing we did was hook it up to the computer (I can't remember which one). Just about every fault code popped up which we agreed didn't make much sense. They cleared the fault codes and the car shuttered a bit (strange...). After this we went for a test drive and the behavior was even more erratic. The car would go to 4000+rpm in 1st and then shift to 2nd. After this test run, we read the codes again and there were none. At this point Wolfgang and Dave were stumped. They suggested two things. First, the selector switch might need to be cleaned, as shogun suggested here: http://forums.bimmerforums.com/forum/showthread.php?p=13874159. Second, the voltage regulators and hence the power to the TCM might be flaky. Since it appeared to be an electrical problem, they were unfortunately, unable to help me. Is there a good way to check the voltage regulators? I'll clean the switch if it really seems to be the problem.

Thanks so much for your help.

Cheers,
-Jason

'88 E32 735i

• 88 735i Transmission problem (won't shift out of 1st) - abyss 2008-08-17 22:18:56 (140 views)
  • FIXED! - abyss 2008-08-31 15:04:25 (100 views)
  • Check all the wires. The S/E/M tarnny switch swap it - alv12 2008-08-18 00:07:54 (69 views)
  • Re: 88 735i Transmission problem (won't shift out of 1st) - az735i 2008-08-17 22:39:28 (65 views)
    • it could a broken wire - shogun 2008-08-17 23:18:22 (71 views)
      • Re: it could a broken wire - abyss 2008-08-18 01:45:20 (62 views)
        • the blower fan problem might be a bad sword (url) - shogun 2008-08-18 03:06:15 (93 views)
          • How to check engine electrics - abyss 2008-08-18 13:28:12 (56 views)
            • that is a good basis for checking - shogun 2008-08-19 01:23:48 (55 views)