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Here it is…I have a 98 Merc C280 that I have a love/hate relationship with.
Monday morning got in it and it started fine despite being below freezing that night. I drove it to an appointment. Came out about a half hour later and went back to the vehicle…key in the ignition…started normally, but stalled 1 second later. Did this at least 10 times. Gave it a little throttle once or twice on start up, but changed nothing.
Only stored code was a pending evap code P0455, which was probably from the morning before. Sometimes registers a pending code on extra cold mornings.
Car ignition is Mercedes infrared EIS system which will not even turn the key if there is a security issue. Tried two keys anyway to rule that out.
Had an extra camshaft and crankshaft sensor laying around as backups, so I changed those out quickly…no fix.
Had the car towed to a garage thinking it was probably fuel pressure related. They tested and said fuel pressure was fine. They googled and said it was probably the key, but they were basing that on older Mercedes DAS ignition system.
I’ve got my battery out currently giving it a full charge to try that, but it is turning the car over so i’m skeptical that will do anything.
I’ve had a slight rattle, which is probably one of the cats, but car has been driving pretty normal, no power loss issues while accelerating.What do you think?
I’m entertaining:
-clogged cat
-fuel pressure regulator
-short somewhere…fuel injectors, plug wires, bad coil pack
-maf sensor (but I would have thought that a failed maf would store a code)
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I would start by diagnosing the P0455 error, and fixing that before anything else.
Your vehicle may have many issues, but you’ll get nowhere through guessing and parts changing. Diagnose and fix one issue at a time.
I know what you are saying, but I don’t think it has anything to do with it in this case. The rubber seal on my gas tank cover is starting to crack and when it gets really cold I get the odd pending P0455 code on a morning start up. Never hangs around long enough to actually set the check engine light. I’m just hoping to find someone that has run into a similar issue before who could point me in the right direction of what to check first, etc.
Missing or loose fuel cap – Incorrect fuel filler cap used – Fuel filler cap remains open or fails to close – Foreign matter caught in fuel filler cap – EVAP canister or fuel tank leaks – EVAP system hose leaking – Fuel tank leaking
Watch this video for your car will explain your code and help u fix it.The evap systems is fuel vapors that drawn into the engine for combustion. There is a vapor hose that runs from the gas tank to a canister and to purge solenoid Watch the video you will learn something .
The stall might be vacuum issue.I’m pretty familiar with the evap system as the other car at home is a Nissan and evap issues are annual for that car. 😛
I guess I just never entertained it for the Merc because the Nissan always started and seemed to run ‘ok’, but it was always the vent valve.
I’ll test the purge valve to see if it is holding vacuum.SOLVED…JUST IN TIME FOR A MERRY CHRISTMAS!
It was electrical….EIS CAN wires
-I had tried crankshaft/camshaft sensor replacement as I had spares in my dash and they are related inputs to starting sequence…No change
-There was fuel pressure
-Changed an engine coolant temp because when I had brought up climate control diagnostics menu…was showing “LO” for sensor reading instead of numeric value, which I thought might had meant an open/faulty circuit. ($20)…no change…and still measured “LO” on the new sensor so must only show a numeric value above a certain temperature…FYI
-Checked all fuses and relays and overvoltage K40 module….no change
-Removed MAF connector…no change
-Pulled ECU and TCM to examine for oil/moisture damage…cleaned small moisture corrosion on bottom of ecu board with MAF cleaner…no change
-Changed the battery because although my other battery was only 2 years old was dropping from 12.4 to 11.9-12.2 V range after just a few attempted starts….no change. (Got refund on old battery…upgraded to AGM )It turned out to be the EIS CAN HIGH/LOW connection(Tiny Green & Green/White wires…smallest connection on EIS)
About a year and a half ago I had removed the EIS to have a key made out of province. That small green connector had broken at the time of removal as it is EXTREMELY delicate, but I had done a quick repair and never had any issues with it since. I had pulled down the EIS after having the fuel pressure checked and changing the crankshaft and camshaft sensor with no luck. When I pulled it down from the dash…the wires for the CAN HIGH/LOW were out of the connector but I thought I must have pulled them apart in the process as it was dark and there is lots of stuff for them to get hung up on when you are trying to pull it down out of the dash. I had quickly tried to hold the wires in the connector port in both configurations to rule this out, but It made no change at that time(could not have been making good enough connection).
A couple days after…I pulled the EIS from the car and fixed the connection at the EIS and made it a little longer to make it easier to reassemble and to rule this out. At that time…I had emailed the guy who did work on my EIS to ask him which side was which(there is one green wire and the other green/white). He sent me a diagram…which i’m pretty sure I followed, but turned out to be wrong. I had ruled out the CAN wiring at this point.Changed the battery today and it didn’t change anything and then decided to switch the wires for the CAN high and low as I had put quick disconnects on each wire where the wire extension met the originals. I was just desperate at this point as I really thought that I had them in the correct spot from the diagram I got.
The only thing that made me go back to the EIS was a code that I wasn’t able to pull from my scanner, but came up on my friends snap-on solus reader. P1570…which is connection between DAS and ECU. My internet search had led me to all kinds of different causes for this code…including shorted wiring, fuses, and bad connectors, faulty ECU, sensors inputs, etc.ANYWAY>>>>>
Bingo…fired up smooth first time. No more stall and the starter was engaging whether I turned key immediately or waited a long time. I did switch the wires again back and forth to confirm that this was the fix.The problem all started because the tiny, tiny green plastic connector for those wires had cracked when I took it out about a year and a half ago. I had put a little super glue on the cracked connector when I put it back in and it never gave me any problems since, but the freezing cold -25’C temperatures must have made the wiring more rigid and torqued it free while it was sitting.
Hope this helps someone at some point. This could happen to anyone with EIS ignition switch…1998 to present. That dam connector is extremely delicate. If you have similar symptoms with similar P1570 and especially if you have done anything to EIS…check your CAN wiring from EIS to ECU.
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