new to this forum so hello everyone and hope you're all having a good day. so i picked up 2 e320's this weekend, a 94 and 95 one with a fuel pump issue which i'm in the process of handling, and another with a weird problem. i am more familiar with bmw's than mercs so bear with me.

it's a 94 so it's got the m104. the problem i'm having is she starts up, then dies literally a few seconds later. sounds good when it's on, but don't know why it just turns off? thanks an advance, and any info would be greatly appreciated.

since i have 2 of the same car, i plan to interchange any suspicious parts between the 2 hopefully helping me solve or pinpoint any other issues at hand; granted that the other part isn't faulty either

since i believe this car has a cold start injector, i do think that is why it starts up for 2 seconds then shuts down. i have swapped the ovp, klima and fuel pump relays and nothing. i've only ordered a ovp so far

hello and welcome,

recently another forum member had a similar problem, turns out his no-start problem was caused by a combination of cold temperatures and water in the fuel tank. here's the link:
M104 will not start you may want to rule that out first.

i believe that the M104's from 1993 on, with HFM engine management, do not have a cold start fuel injector.

The majority of M104's had 2 major problems: 1) head gasket(poorly designed) 2) wiring harness(biodegradable wire insulation).

If both have already been replaced then you're in luck, the no-start problem is probably something simple like : 1)faulty ECT sensor(important for cold starts), 2) old/wrong spark plugs, 3) faulty under coil connectors, 4) fuel pump relay, or 5)major vacuum leak(s).


you should also build a code reader which will allow you to pull the Diagnostic Trouble Codes from the engine's computer. Check out the following thread which explains how to build it, specifically post#11: Reading Codes

PS i believe that the numbers in the diagram are Radio Shack part numbers, should make obtaining the proper parts easy.


good luck

thank you for the response. you're right about them being part numbers and thank you for referencing that to me. as we speak i'm at radio shack with soldering iron, wires, & everything i think i need for the led test kit.

as far as weather being an issue, i live in south west florida so it's fairly hot/warm throughout the day. & maybe you misread because the car does start just dies right after even if i get on the gas.

i could've sworn i replied? must've not went through. i don't think the cold weather is the issue because of the fact that i live in southwest florida. thank you for the response and referencing the home made code scanner. i made mine last night. you're correct about them being part #s at RadioShack but not everything on the list was found & i used a few different pieces. no resistor (12v LED), different SPST switch, no fuse, but it'll work all the same. I'm going to check the crank position sensor and replace that if it's faulty. ill be back later with results

another thing i forgot to mention was that the car does start, just doesn't want to stay on.

An engine needs spark, compression and fuel to run.

Assuming that your compression is good, then it's either spark or fuel that is missing.

Next time you start the car, watch the tach as the engine shuts off.

If the tach is running at x rpm, then suddenly drops to zero, it's likely the ignition is tripping out.

If the tach slowly drops as the engine winds down, then no fuel is the likely culprit.

Jim

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14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles

might be your coolant sensor

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

thank you everyone for the input. very appreciated and i got some good news i pulled some codes:

pin 6 - 4, 5, 6, 8
pin 8 - 4, 11, 24
pin 14 - 2, 5, 11

&

i got the car started, running and i even drove it a little without it dying on me at all. as of now it starts right up but the idle is a little shaky but i believe that is the blame of the loud & leaky fuel pumps.

tomorrow i'm gonna start it up again and this time let it warm up to see if it has any warm start problems or anything else for that matter.

one weird thing that happenes is that the wipers operate even if i haven't switched them on when i was cranking it and fuse #7 went out after the short drive. i replaced it and it fired right up again.
also the parking & cluster lights don't work anymore but both the headlights still do?

any ideas as to why that might happen? thanks again in advance!

update @ 10.50am: started her up again, checked for some more codes:
new - pin 3: 3, 12
additional - pin 8: 46, 49
i have also checked my wiring harness and the harness to the ETA. the main is fine, but the ETA will need to be rewired. the idle isn't too crazy but it's not smooth either.

UPDATE: rewired the eta and although i'm a noob, i will leave my 2 cents to anyone looking to do this

i would recommend going with a dremel type tool for best results. if done correctly you can even remove the pin holder and solder the new wires directly to the pins instead of soldering new wires to the old ones attached to the pins. i will also post a picture of the map of the circuit board in the actuator so if anyone is confused or mixes up a wire or 3 like i did, you can easily get around it. also using a dremel will cut the time to take the connector apart in half, literally.

another tip is to use 18, 20, & 22 gauge wire. if i remember well there are: 2x 18g, 3x 20g, & 4x 22g wire. and length would be to play it safe a 18in each wire. the wire inlet on the actuator really doesn't stretch so using one gauge of wire unless it's 22 just won't happen.

after installing the rewired eta, my car idled at 1500 and when i went on the gas it would sputter and almost die, so i knew the eta had to have been the problem since prior to, i was able to drive it, rev it, and the only issue was the shaky idle.

what happened was that got wires 8, 6 & 14 mixed with each other (long story) but it is sorted now, i even got the DTC 6(idle control inoperative) on pin 3 using the cars check light. tomorrow i will reinstall it and see how it goes & keep you guys posted. thanks everyone for the advice. it has really helped! good day and god bless, jean.

UPDATE: swapped eta from other car to this one since after rewiring my eta the car ran worse than before. with new pumps in, new ovp, battery fully charged, and 2 gallons of 93, it was ready to go and to my surprise after only cranking it a few times, it started up with NO issues at all. a few days into driving the check engine light came on, i ran the code and it came up with the o2 sensor having an issue (code 12 i think?) fast forward to a few days, check engine light still on but no drivability issues, not even overheating. the idle would sometimes go up and down in gear but it hasn't done it at all since the first day i got it running.

fast forward to a few days after that, i had disconnected the battery because the car wouldn't start due to the fuel/ignition cut out that didn't disengage after unlocking the car from the driver door. i guess there's a problem with the driver lock or maybe a sensor is trippin cause it has to be unlocked from the passenger side for it to disengage.

anyways, the check engine light has disappeared since then and hasn't come back on at ALL. with only 60 miles so far on it since the replacement, everything looks good.

i would have put more miles on it, but i'm selling the car so i can crawl get back into a bmw.