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Just finished repairs that included a new CKP and MAF sensor. When it up and died at a busy intersection, the codes showed CKP and MAF. It would'nt idle and would stall out. If I kept my foot on the gas it would stay running and that's how I limped it home. I replaced the CKP sensor first and things got better. Still wouldn't idle nice but didn't stall out. Then I put in the MAF and everything was fine again. Then 2 week later I got stranded at the SuperMarket cause it won't start. Cranked but no start. 45 minutes later it started fine with no rough engine behavior at all. A few days later I took it out for a long test drive and returned home. I waited 10 minutes. Then it wouldn't start. No Check Engine Light, no codes thrown, fuel pumps are running, fuel pressure in the supply rail is 50 psi. Waited about 45 minutes and it started fine. Any ideas?
 

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Just finished repairs that included a new CKP and MAF sensor. When it up and died at a busy intersection, the codes showed CKP and MAF. It would'nt idle and would stall out. If I kept my foot on the gas it would stay running and that's how I limped it home. I replaced the CKP sensor first and things got better. Still wouldn't idle nice but didn't stall out. Then I put in the MAF and everything was fine again. Then 2 week later I got stranded at the SuperMarket cause it won't start. Cranked but no start. 45 minutes later it started fine with no rough engine behavior at all. A few days later I took it out for a long test drive and returned home. I waited 10 minutes. Then it wouldn't start. No Check Engine Light, no codes thrown, fuel pumps are running, fuel pressure in the supply rail is 50 psi. Waited about 45 minutes and it started fine. Any ideas?
What a lonely thread. This problem went away suddenly. I'm not planning any long drives that's for sure.
 

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Fuel pressure regulator? Pretty easy to swap out.
Ya ...at this point throwing parts at these old cars is just shooting in the dark. Since it's a heat related issue, it has been suggested that when this "hot no start" occurs, take a gallon of cold water and carefully pour it on the bell housing around the CKP sensor(rather harmless). From there, fast cool the area around the engine heat sensor. After that try a can of "cold spray" on the CMP sensor, Diagnostic Module, and ECU. Go slow and don't do all this at once without trying to start the engine each time.
I've read other car threads that suggests this technique with good results. So I got my cold spray ready and a gallon of water in the trunk. Gotta wait now and see if I can catch this rotten fish.
 

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Intrigued...sounds plausible. Let us know if this works. Did you take CPS resistance values at various temperatures?
 

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It would help if you mentioned the state of the engine wiring harness and the throttle harness.
Hopefully both are replaced with non-eco junk already.

Otherwise you will be chasing ghosts.....

- Cheers
 

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It would help if you mentioned the state of the engine wiring harness and the throttle harness.
Hopefully both are replaced with non-eco junk already.

Otherwise you will be chasing ghosts.....

- Cheers
CKP is new. Taking CKP resistance readings at different temperatures is tough because it's so hard to get at. The Engine harness was changed out at the Dealership along with the throttle body a few years ago by the previous owner. It cost him thousands. That throttle body failed last year. It went into limp mode and the cruise control stopped working. Got a replacement that had a new wire harness. Turns out the internal electromagnetic coil burns open eventually. Then the ECU can't grab control of the butterfly valve.
 

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CKP is new. Taking CKP resistance readings at different temperatures is tough because it's so hard to get at....
Hard to get at??? Come on now, you take the Ohms readings at the plug end of the crank sensor located inside the fake firewall next to the diagnostic socket.
 

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Hard to get at??? Come on now, you take the Ohms readings at the plug end of the crank sensor located inside the fake firewall next to the diagnostic socket.
Right. Forgot about that. Pin 29 and 30 at the ECU plug goes to the CKP sensor. I'll do a cold/hot comparison. This is like when you go to the Doctor and now all your symptoms are gone. Haaaaa.
 

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Right. Forgot about that. Pin 29 and 30 at the ECU plug goes to the CKP sensor. I'll do a cold/hot comparison. This is like when you go to the Doctor and now all your symptoms are gone. Haaaaa.
Update. My "hot engine no start" problem occurred again today. Got home, shut the car off, set a timer for 10 minutes and then tried to start the engine again. It was all crank no start!!! I moved quickly and poured cold water over the bell housing in the area of the CKP sensor(nice and slow and about 1 gallon). The engine started!!! As mentioned at the top of this thread, I replaced the CKP and MAF last summer when the engine died. The codes pointed at these components. I guess I bought a bad CKP sensor. Stay tuned everyone and thanks for all the input so far.
 

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Update. My "hot engine no start" problem occurred again today. Got home, shut the car off, set a timer for 10 minutes and then tried to start the engine again. It was all crank no start!!! I moved quickly and poured cold water over the bell housing in the area of the CKP sensor(nice and slow and about 1 gallon). The engine started!!! As mentioned at the top of this thread, I replaced the CKP and MAF last summer when the engine died. The codes pointed at these components. I guess I bought a bad CKP sensor. Stay tuned everyone and thanks for all the input so far.
Jeebus, what absolute madness. I hope this isn't the handwriting on the wall; new parts failing with regularity. :(

Maybe we should start a list of new raditors, new clutch fans, new dist caps, new water pumps and new CKP sensors etc known to fail by BRAND designation.

It sure sounded to me like it was the CKP sensor all along, but replacing it should have ruled that one out.

Kevin
 

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Jeebus, what absolute madness. I hope this isn't the handwriting on the wall; new parts failing with regularity. :(

Maybe we should start a list of new raditors, new clutch fans, new dist caps, new water pumps and new CKP sensors etc known to fail by BRAND designation.

It sure sounded to me like it was the CKP sensor all along, but replacing it should have ruled that one out.

Kevin
I bought the CKP sensor in August from Amazon.com. Seller name is "OEM Parts 4 Export". It's made by a company called FAE. I just got an email today stating that the seller refuses to send a warranty replacement stating the "return item" time period has expired. Should have just bought a good old BOSCH Brand.
And yes there needs to be a "don't buy" list by Brand name.
 

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I bought the CKP sensor in August from Amazon.com. Seller name is "OEM Parts 4 Export". It's made by a company called FAE. I just got an email today stating that the seller refuses to send a warranty replacement stating the "return item" time period has expired. Should have just bought a good old BOSCH Brand.
And yes there needs to be a "don't buy" list by Brand name.
Yeah, we should probably have some stickies on this. OEM does not equate to OE. Yeah, it might be the same manufacturer as originally made parts for MB. But there is no assurance today that they fit and/or are of the same quality. And if you're relying on 'vendors' to be honest, I have some interesting swamp land in Florida to sell........

Yrs ago I went the eBay OEM route and also ordered that way from a jobber online. 95% of those parts failed prematurely....and I was paying almost the same as OE. Big lesson learned there and switched to parts.com when they were using MB dealer networks to sell parts. Then, that went to hell. So....long story short is that word of mouth is about all we've got....short of OE parts and even MB dealer networks are straying from German made parts.

Let's all face the fact that MB Germany is long past the point of supporting our cars and they actually did so long after their legal obligation. It's up to us now to sort out the fakers, shakers and liars.

Kevin
 
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