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liljos
11-21-2011, 12:36 AM
so today I changed my stock fuel pump for a tre performance 340 one. my car has been having idling problems for sometime now and hasn't wanted to start when it's a bit warmed up. today I started the car after having the pump replaced and it seemed to run better than before. but as soon as I got excited about it running it dies down. what I'm wondering is that maybe my ignition coil gets too hot and can't give a signal when warmed up? the car will crank but it won't start. possible air leak? what I've replaced: spark plug wires, fuel pump(seemed to cure idle), fuel hoses under hood. what i think needs to be changed: spark plugs, ignition coil, ignition rotor, distributor cap. any thought on if this will fix my problem? any advice? thank you and good day.

shogun
11-21-2011, 02:12 AM
crankshaft position sensor? read this how to test
How To Test CPS? (http://www.bimmerboard.com/forums/posts/645000)

liljos
11-21-2011, 10:42 AM
crankshaft position sensor? read this how to test
How To Test CPS? (http://www.bimmerboard.com/forums/posts/645000)

i'm gonna run a test on that using the Bentley manual. but yesterday i decided to check my cars codes and it's been giving my 1223 - coolant temperature sensor

liljos
11-22-2011, 08:04 PM
shogun after looking up prices for the cps, i noticed a problem. there seems to be 2? one on the coil wire(1) and the other seems to be located on the block(2)

Crankshaft Position Sensor | AutoZone.com (http://www.autozone.com/autozone/parts/_/N-9gslr;jsessionid=6C0645DE0E6D41C2DC10ACAF1705EC44. diyprod2-b2c4?filterByKeyWord=crackshaft)

if that doesn't work go to AutoZone Auto Parts Stores | Motor Oil, Exhaust Systems, Suspension Parts, Car Starters, Car Stereo, Radiator Hoses, Headlights, Car Accessories, and More - AutoZone.com (http://www.autozone.com) and the part #'s are 1. SU8198 and 2. SU5139

if you were referring to the first one, then mines is brand new as it came with the brand new set of spark plug wires i purchased.
do e34's with the m20 have one or 2?

genphreak
11-23-2011, 06:48 AM
The sensor on No.1 spark plug wire is an inducer that helps the ECU know when the spark is actually happening. The crank position sensor is on the timing wheel, that little fella is what normally fails. Check also that your plgs are properly gapped, The coil can be tested, and for M20 u can get a 2nd hand replacement for cheap. Have you checked all your intake pipes and connections are achieving a strong vacuum in the head (hard to do if its running but always deserves a good check)

liljos
11-23-2011, 09:20 PM
The sensor on No.1 spark plug wire is an inducer that helps the ECU know when the spark is actually happening. The crank position sensor is on the timing wheel, that little fella is what normally fails. Check also that your plgs are properly gapped, The coil can be tested, and for M20 u can get a 2nd hand replacement for cheap. Have you checked all your intake pipes and connections are achieving a strong vacuum in the head (hard to do if its running but always deserves a good check)

alright all tests completed. i got the fuel pump to run(blown fuse), tested the resistors(normal range), tested the CPS and got a solid reading of 533 so thats normal(bentley manual says 540 +/- 10% is normal). after all that the car started. it stayed on and the idle kind of smoothend out. I took it for a drive about 0.4 miles then parked it.

as soon as I did that and opened the hood, opened the throttle a bit, the car died. now according to the code test I ran yesterday, there's something wrong with my coolant temperature sensor (1223). on top of that my sendor isn't working as I noticed my temperature reading on my cluster didn't increase after the short run. both the coolant temp sensor and sendor are new but don't seem to be working. does anyone know what a faulty sensor would do to an m20? i've heard it does quite a deal. and in my theory the car shuts down after it warms up due to the faulty sensor. comments? thank you.

update: i've allowed the car to cool down. went to start it and it fired right up! -_____- i'm really putting my money on a faulty sensor.

genphreak
11-26-2011, 07:21 AM
Just measure the sensor outputs with a multimeter and check the Bently.

If you got a code for the ECU one, change it.

The sensor that runs the gauge doesn't matter much, only affects the gauge needle reading- not engine management. A faulty sensor will cause incorrect timing and fuel ratios- and confuse the ECU. Dep. on how the sensor is failing, it could flood the engine at start or cause a lean condition- or both in different ways at different times.

genphreak
12-06-2011, 06:00 AM
PLs don't make me try to work out what you mean by sendor and sensor. Your car has 2 different coolant temperature sensors installed, one for the dash gauge, one foe the ECU. Don't mix up the wires between them, and if the plugs on them are the same, test to make sure no-one else has before you (common problem). If you make sure the engine one is right, the car will run ok as the ECU can work out how much fuel and air and spark it needs. Assuming your fuel pump is working (and it sounds to me like it is a possibility that it could be on the way out) you'll be ok.

No biggie if it is, TRE Performance Inc. - SPEC AFR Canton Corbeau RC Walbro 255LPH Fuel Pumps (http://www.treperformance.com) have awesome pump replacements cheap. If the gauge sensor is bad, it will run fine anyhow.

liljos
12-06-2011, 07:23 AM
PLs don't make me try to work out what you mean by sendor and sensor. Your car has 2 different coolant temperature sensors installed, one for the dash gauge, one foe the ECU. Don't mix up the wires between them, and if the plugs on them are the same, test to make sure no-one else has before you (common problem). If you make sure the engine one is right, the car will run ok as the ECU can work out how much fuel and air and spark it needs. Assuming your fuel pump is working (and it sounds to me like it is a possibility that it could be on the way out) you'll be ok. No biggie if it is, TRE Performance Inc. - SPEC AFR Canton Corbeau RC Walbro 255LPH Fuel Pumps (http://www.treperformance.com) have awesome pump replacements cheap. If the gauge sensor is bad, it will run fine anyhow.my fuel pump currently is the tre performance 340 255. and it's actually working fine. i found a vacuum leak which i strongly believe is the cause of my idle problems and i am getting new sensers, ICV, and O2 sensor from a member from bimmer forums. in addition to that i'm also changing my spark plugs. the vacuum leak is part #6 which is the fuel hose for the fuel tank breather valve that connects right unber the TBhttp://static.bmwfans.info/images/epc/MTg3NF9w.png