Author Topic: sickly e36 with phantom cel fault code (Read 4112 times)

fast_eddie · « **on:** December 10, 2008, 02:07:38 PM »

Hello, ive got a good question for all you die hard bimmer fans out there but first I would like to introduce myself for this is my first post to m42club. Ok, my name is Eddie, im 17yoa, and I just bought my first bmw in October. So far I love the car, besides the little technicalities that have come along with it. For one I paid 2200 for my 95 318is with 160000 miles on it, I thought it was a decent deal when I first got it. But then I started noticing faults�. It needs control arm bushings, balljoints, swaybar links, right engine mount, and some body work. All in all im still really into this car and plan to restore it to better than OEM condition. But ive kind of ran into a stump. My car suddenly lost its great perkiness and started hesitating, bogging, and acting like it wasn�t getting enough gas or maybe too much. It is getting horrible gas mileage (went from over 130 miles to 1/4tank to 75 miles to 1/4tank). A mechanic told me my fuel filter might be clogged up so I replaced that to no avail. So I got online researching and I found a thread about check engine light fault codes for the e30 and e36 models. Well I tried it and it worked great, I got my code and went back to the computer and I guess my code either doesn�t exist or just doesn�t appear on the code dictionary. The code is 1238. i called a couple shops asking them if they can diagnose my car. they tell me they have the right computer. then when i show up they dont have the right f'n connector. ive allready been to 3 shops.

ShabbaPlanks · « **Reply #1 on:** December 10, 2008, 04:20:06 PM »

Go and pull the code again, you might have taken it down wrong??
1237 is the closest I could find, no referance to 1238. With a bit of luck you might have taken the code down wrongly and with the right code we can help you to fault find.
I noticed your engine mount was worn, that can lead to unwanted movemant which in turn can cause leaks tears in the exhaust manifold. Quite a common problem, which would give similuar running faults to those you are having.

Check for intake leaks with smoke and check for exhaust leaks...its not much but its a starting point. Also pull your 02 sensor and visually inspect, if its looking sooty or you dont know if its been changed from new, replace it. If you have misfires dont drive the car untill you get it sorted as you may fry the cat converter.

fast_eddie · « **Reply #2 on:** December 11, 2008, 09:39:23 AM »

ya, i have checked and rechecked atleast 10 times seeing if thats the only one and its always the same. my abs light is on, could that pull that code? i had the sensor before the cats out b4 to change tranny fluid and it looked fine. how do you check for intake leaks? with smoke? and i hope i didnt fry em because sometimes it runs awesome then it starts missing and bogging. another symptom is the mpg meeter swaying at a steady speed. i have been lead to believe that it might be the throttle positioning sensor. what would that look like if it was faulty? when i got the car the vacume line was taped, it seems to still be taped fine, u think that could be the culprit?

nc_bboy · « **Reply #3 on:** December 11, 2008, 10:17:14 AM »

You know what I've had the same problem with my 92 318is. Its been sitting there for two years in my driveway because my coil pack died..but after I replaced them and finally got it running again. BTW i did the COP conversion that I bought from rob_e30. He sells them on this forum. well anyways the CEL was still on. I went for a really long drive to see if it would still hestiate or bog down but it didn't. But its making me angry that the CEL won't go away. Two years ago I didn't know how to pull the code. But I tried to after I got the car running, and it wouldn't pull up the code or flash. The light just stayed on. Well anyways, I think it might be your coils. If you change them out and it works let me know! I hope this helps lol even though I was rambling on for a while.

Edit: Also other shops usually don't have the right things to do a diagnostic test for the 318is for some reason. Or atleast thats what it seems like. You might want to try the dealership, even though they'll charge you a freaking arm and a leg lol.

fast_eddie · « **Reply #4 on:** December 11, 2008, 01:37:09 PM »

rambeling perfectly acceptable. i guess i can just grab one of the old plugs i pulled out of and test the coils. today im going to check for leaks as best i can, untill someone explains how to do it with smoke, pull the plugs, and test the coils. if i dont find anything ill pull the throttle positioning sensor and inspect that.

nc_bboy · « **Reply #5 on:** December 11, 2008, 03:24:06 PM »

yeah that was the next thing I was going to say to check. I didn't change mine or inspect it but that's because I changed the coils and the problem went away. But yeah the car was handed down to me after my older brother abused it lol. But he took it for granted..but hes changed his ways. I seen your other thread about a rebuild, your on the same path as me lol. Planning to rebuild but going the turbo route. Well again good luck with finding whats causing the problem.

fast_eddie · « **Reply #6 on:** December 12, 2008, 07:30:49 AM »

yesterday i found that the vacume line had a massive crack in it, i pulled it off and fixed it the best i could. i had to pull the throttle body off to put it back on. got it all back togeather and it didnt help a bit. so i started playing with sensors and they all seemed to be ok. the throttle position sensor was kindof sloppy. are they like that? well then i started testing spark with a little lighted link that i got from my frend, they all sparked fine. i pulled the brand new plugs (350 miles) and in cylinder 3 the plug was leaking around the ceramic. hope it works

roundel318 · « **Reply #7 on:** December 12, 2008, 08:15:01 AM »

Can you take a picture of your engine bay?
Your car could be so late in 95, it could be a OBD II car with a M44?
As for OBD 2 codes, lets take a look

P1238 Fuel Pump Secondary Circuit Malfunction
B1238 Over Temperature Fault
C1238 ABS Hydraulic Pressure Differential Switch Input Circuit Failure
U1238 SCP (J1850) Invalid or Missing Data for Experimental #4

Probably a good idea to run down a volt meter and get after your fuel system

As for cracked plugs, might make sure that isn't your problem, albiet I don't feel it would be.

fast_eddie · « **Reply #8 on:** December 16, 2008, 07:35:32 AM »

ya the code might be the abs because the light is on and it doesnt work. i fixed the vacume and put new plugs in it and ive been to 2 more shops. still no1 with a computer. my exhaust seemed like it was louder and somethiong in it would rattly when it was revved up. advanced auto in alpena told me it was probabally the cat's. looks like a good oppertunity to improve preformane and maby fix it at the same time. so yesterday i took the exhaust off, today im going and getting a pipe bent up for me. im not shure what i need for a muffler. do they require backpressure or is an open exhaust enough? you can get away with stuff like that whair i live

roundel318 · « **Reply #9 on:** December 16, 2008, 11:05:34 AM »

Find a BMW shop with a OBD II tool.
Tools are easy to find, just with the appropriate connector.
Also, try the Roundel magazine, someone might have a CCA chapter in your area that would have someone good to go to and not be a dealer.

fast_eddie · « **Reply #10 on:** December 19, 2008, 07:55:38 AM »

i went to advanced auto, they supposedly have obd computers for all cars, well not e36's. they siad that it is probabally my cats. so i choped off my exhaust and had a new exhaust from the hedder back profesionaly built and installed (122.69). sounds really good when it is hitting on all cylinders. still didnt fix it. i would like to rebuild the ecu with new sensors. does anyone know whair i can buy all of or most of the sensors at 1 time and get a pretty good deal?

roundel318 · « **Reply #11 on:** December 19, 2008, 09:07:38 AM »

Probably on Pelican?
Your crank position sensor should be the first one you change out.
If plugs / wires / coils don't address this, the ECU controls those with readings from the CPS.

fast_eddie · « **Reply #12 on:** December 19, 2008, 09:44:09 AM »

i havent replaced the wires or coils. they seem to work fine. i put spark testers between the plug and the wire on all cylinders and they were fireing fine. im thinking that if my cats were heating up too much or causeing too much backpressure that the o2 sensor on the pipe could have burnt up. and i need to change/clean the plugs again, one cylinder doesnt fire 75% of the time. can i just sprat the sensors down with electronic contact cleaner and maby revive them a bit?

fast_eddie · « **Reply #13 on:** December 19, 2008, 09:46:19 AM »

oh ya and now the 1238 code is gone and replaced by 1222. lambda? something about bad fuel ratio. could that be from that sensor?