Very rough start-up/idle in the mornings or when cold and CEL?
02-12-2009, 05:20 PM
#52
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02-12-2009, 08:53 PM
#54
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Thread Starter
02-13-2009, 03:04 PM
#55
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Thread Starter
I started it up cold this morning and it was not as rough as it used to be. However, it began to get rough and just like amaonfire's post below, it got better with a bit of gas ...
I think cleaning the throttle body might be a good thing for it...
yeah, I'm kind of worried that that's it as well... 
I think cleaning the throttle body might be a good thing for it...
I've been having the same problems on startup, a rough idle for a moment, yet if I give it a bit of gas it goes away.
No CEL, and no codes logged. Gas mileage is great, engine idles perfectly after, ... so I've ignored it for now.
If it is indeed the recirc valve getting stuck, oh well, pressing the gas seems to unstick it.
No CEL, and no codes logged. Gas mileage is great, engine idles perfectly after, ... so I've ignored it for now.
If it is indeed the recirc valve getting stuck, oh well, pressing the gas seems to unstick it.
02-13-2009, 04:09 PM
#56
Super Moderator
Phil, clean the throttle body, then put it on two consecutive full tanks of fuel with Techron concentrate.
02-13-2009, 05:26 PM
#57
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Thread Starter
Are their any gaskets or seals that I might as well replace while I'm in that area?
John, can you please help me do this one weekend?
Thanks again guys!
02-21-2009, 03:00 PM
#59
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Thread Starter
I took it to the dealer today to have them put in the engine cover... they gave me the updated engine cover at least:
the manager came out to see me and apologize. I showed him the engine and the transmission tab and they put in a new one for me for free.
John and I are going to do the throttle body cleaning in a few weeks or so
thanks John!
The car seems to be running better though... I put in some Techron Concentrate Plus in for good measure last weekend as well.
the manager came out to see me and apologize. I showed him the engine and the transmission tab and they put in a new one for me for free.
John and I are going to do the throttle body cleaning in a few weeks or so
thanks John!The car seems to be running better though... I put in some Techron Concentrate Plus in for good measure last weekend as well.
02-21-2009, 05:59 PM
#60
Super Moderator
Ah! - Good news - let us know how things go after you've put on some mileage.
02-21-2009, 08:50 PM
#61
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Thread Starter
AHHHHH!!!!!
Not good news anymore
I drove it on some errands for about 75 miles total today, I stopped and started it about 12 times. On the 9th start, the CEL came on. The only thing I did was get around 4 gallons of gas from Chevron (the car had 3 gallons left from the tank that I had put Techron in, so I didn't want to dilute it that much more). The 9th stop and start was about the 4th stop/start cycle or 15-20 miles after I got gas. When I've tightened the gas cap, it has felt like there has been more play of sorts on it lately...
So, I decided to just go to Harbor Freight and buy the CAN OBDII reader that johnand recommended. I got a slightly different model (it was the only one they had): http://www.harborfreight.com/cpi/cta...emnumber=98568. But it works and it was only $39.99...
It popped the same exact code again: P0456
The car is running perfectly fine, but the damn CEL is on. Should I just clear it and see if it comes back again? I checked the gas cap and it was on securely. Maybe I should buy a new gas cap...
Not good news anymore
I drove it on some errands for about 75 miles total today, I stopped and started it about 12 times. On the 9th start, the CEL came on. The only thing I did was get around 4 gallons of gas from Chevron (the car had 3 gallons left from the tank that I had put Techron in, so I didn't want to dilute it that much more). The 9th stop and start was about the 4th stop/start cycle or 15-20 miles after I got gas. When I've tightened the gas cap, it has felt like there has been more play of sorts on it lately...
So, I decided to just go to Harbor Freight and buy the CAN OBDII reader that johnand recommended. I got a slightly different model (it was the only one they had): http://www.harborfreight.com/cpi/cta...emnumber=98568. But it works and it was only $39.99...
It popped the same exact code again: P0456
The car is running perfectly fine, but the damn CEL is on. Should I just clear it and see if it comes back again? I checked the gas cap and it was on securely. Maybe I should buy a new gas cap...
02-22-2009, 11:48 AM
#62
Super Moderator
Phil - Darn thing. There is no doubt that you have a minor leak somewhere in the EECS. It's a minor thing but you don't want CELs on. Just cancel it & see if it returns which I suspect it will. When you do the throttle body with splinter you can check the piping that end. The dealer has smoke tested & found nothing. I hope they did it under slight pressure as required?? It could well be the gas cap seal or control valve playing up. Do you have a buddy with a similar car that would be prepared to swap gas caps for a day?. If he get's a code & you don't you have the answer. You can now cancel his code for him. The little scanner you bought is just fine. I hate throwing parts at things until I know what's wrong. I do suspect the cap but it might just be a loose or cracked hose - They have replaced the charcoal canister. I don't know what method they used to check the EECS - If they used a unit that smokes via the fuel fill pipe then they did not check the cap. The ones I'm familiar with tap into the EECS pipework so they do check the cap. It is significant that it happened after a refuel because that's when you give the evapourative control system a hard time. On no account use compressed air to check the system - it's dangerous! Is it more inclined to trigger a code with a full tank than an approaching empty one?
The good news is at least that the vehicle is running well - If the charcoal canister was saturated it would cause the vehicle to run a bit rich.
I would wait until you clean the throttle body with splinter. If the problem persists after that you need to either go back to the dealer & tell them they messed up with the EECS or throw a new fuel cap at the problem.
Good luck
The good news is at least that the vehicle is running well - If the charcoal canister was saturated it would cause the vehicle to run a bit rich.
I would wait until you clean the throttle body with splinter. If the problem persists after that you need to either go back to the dealer & tell them they messed up with the EECS or throw a new fuel cap at the problem.
Good luck
Last edited by Glyn M Ruck; 02-22-2009 at 11:52 AM.
02-22-2009, 05:16 PM
#63
Super Moderator
Thread Starter
thanks so much Glyn! I really appreciate all of your help. You are truly an asset to MBW.
I've noticed that the CEL has gone on when the tank was closer to empty.
I've noticed that the CEL has gone on when the tank was closer to empty.
02-23-2009, 03:22 AM
#64
Super Moderator
The times you will likely have the greatest vapour pressure in the system are when you are filling up but your fancy American fuel pumps have a vapour recovery system on them - recovery pipe over the main feed nozzle - and when the tank approaches empty where you have the greatest air/vapour space. The fuel can slosh around, effectively providing a larger fuel to air in the tank surface area.
Last edited by Glyn M Ruck; 02-23-2009 at 03:30 AM. Reason: typo
02-23-2009, 01:27 PM
#65
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2002 C230K, 2013 BMW 328, 2015 BMW X5
Phil - Darn thing. There is no doubt that you have a minor leak somewhere in the EECS. It's a minor thing but you don't want CELs on. Just cancel it & see if it returns which I suspect it will. When you do the throttle body with splinter you can check the piping that end. The dealer has smoke tested & found nothing. I hope they did it under slight pressure as required?? It could well be the gas cap seal or control valve playing up. Do you have a buddy with a similar car that would be prepared to swap gas caps for a day?. If he get's a code & you don't you have the answer. You can now cancel his code for him. The little scanner you bought is just fine. I hate throwing parts at things until I know what's wrong. I do suspect the cap but it might just be a loose or cracked hose - They have replaced the charcoal canister. I don't know what method they used to check the EECS - If they used a unit that smokes via the fuel fill pipe then they did not check the cap. The ones I'm familiar with tap into the EECS pipework so they do check the cap. It is significant that it happened after a refuel because that's when you give the evapourative control system a hard time. On no account use compressed air to check the system - it's dangerous! Is it more inclined to trigger a code with a full tank than an approaching empty one?
The good news is at least that the vehicle is running well - If the charcoal canister was saturated it would cause the vehicle to run a bit rich.
I would wait until you clean the throttle body with splinter. If the problem persists after that you need to either go back to the dealer & tell them they messed up with the EECS or throw a new fuel cap at the problem.
Good luck
The good news is at least that the vehicle is running well - If the charcoal canister was saturated it would cause the vehicle to run a bit rich.
I would wait until you clean the throttle body with splinter. If the problem persists after that you need to either go back to the dealer & tell them they messed up with the EECS or throw a new fuel cap at the problem.
Good luck
This goes back to something that my smog guy told me about MB gas caps...they suck. Plain and simple. The seal provided is poor at best. Even when new. I'd offer mine, but I know my is not 100% because to pass my car on the cap test, I had to put a bit of ahhhh sealant on the cap.
Maybe just buy a new one and if it doesn't work, take it back.
E
02-23-2009, 02:21 PM
#66
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2007 C230SS; 2014 ML350 BT
AHHHHH!!!!!
Not good news anymore
I drove it on some errands for about 75 miles total today, I stopped and started it about 12 times. On the 9th start, the CEL came on. The only thing I did was get around 4 gallons of gas from Chevron (the car had 3 gallons left from the tank that I had put Techron in, so I didn't want to dilute it that much more). The 9th stop and start was about the 4th stop/start cycle or 15-20 miles after I got gas. When I've tightened the gas cap, it has felt like there has been more play of sorts on it lately...
So, I decided to just go to Harbor Freight and buy the CAN OBDII reader that johnand recommended. I got a slightly different model (it was the only one they had): http://www.harborfreight.com/cpi/cta...emnumber=98568. But it works and it was only $39.99...
It popped the same exact code again: P0456
The car is running perfectly fine, but the damn CEL is on. Should I just clear it and see if it comes back again? I checked the gas cap and it was on securely. Maybe I should buy a new gas cap...
Not good news anymore
I drove it on some errands for about 75 miles total today, I stopped and started it about 12 times. On the 9th start, the CEL came on. The only thing I did was get around 4 gallons of gas from Chevron (the car had 3 gallons left from the tank that I had put Techron in, so I didn't want to dilute it that much more). The 9th stop and start was about the 4th stop/start cycle or 15-20 miles after I got gas. When I've tightened the gas cap, it has felt like there has been more play of sorts on it lately...
So, I decided to just go to Harbor Freight and buy the CAN OBDII reader that johnand recommended. I got a slightly different model (it was the only one they had): http://www.harborfreight.com/cpi/cta...emnumber=98568. But it works and it was only $39.99...
It popped the same exact code again: P0456
The car is running perfectly fine, but the damn CEL is on. Should I just clear it and see if it comes back again? I checked the gas cap and it was on securely. Maybe I should buy a new gas cap...
Glad the el cheapo Harbor Freight scanner worked for you. I typically recommend buying quality tools, but that thing can't be beat for the price for an occasional scan.
Sorry I don't have anything to add, but Glyn has got you more than covered. Those intermittent problems really can be frustrating to track down and fix. Good luck!
02-23-2009, 03:55 PM
#67
Super Moderator
This goes back to something that my smog guy told me about MB gas caps...they suck. Plain and simple. The seal provided is poor at best. Even when new. I'd offer mine, but I know my is not 100% because to pass my car on the cap test, I had to put a bit of ahhhh sealant on the cap.
Maybe just buy a new one and if it doesn't work, take it back.
E
Maybe just buy a new one and if it doesn't work, take it back.
E
America is so good about returns. Here they would not dream of taking it back & if by some miracle they did they would charge a 25% restocking fee
02-23-2009, 04:36 PM
#68
Super Moderator
Thread Starter
thanks so much guys!
well, I went to BH Benz today during lunch and picked up the gas cap. they wanted $23 something at first and I haggled down to $17
(I know it's cheaper online, but to have to wait and pay shipping, I figured it would be better to just buy it in person.)
I'll put it in tonight and clear the code.
in other news, I got the isolating wires and a filter from getmercedesparts.com on Friday. well, they sent me a filter, an oil filter! I ordered the air filter. so, I e-mailed them and they apologized and said that they would ship me out a new air filter today and that I should just keep the oil filter free of charge b/c I'll eventually need it and it was their mistake. great service.
well, I went to BH Benz today during lunch and picked up the gas cap. they wanted $23 something at first and I haggled down to $17
(I know it's cheaper online, but to have to wait and pay shipping, I figured it would be better to just buy it in person.)I'll put it in tonight and clear the code.
in other news, I got the isolating wires and a filter from getmercedesparts.com on Friday. well, they sent me a filter, an oil filter! I ordered the air filter. so, I e-mailed them and they apologized and said that they would ship me out a new air filter today and that I should just keep the oil filter free of charge b/c I'll eventually need it and it was their mistake. great service.
02-23-2009, 05:28 PM
#69
MBWorld Fanatic!
I think I already mentioned this, but my 05 C230 had an elusive small evap. leak last year. It took three or four trips to the dealer before it turned out to be a slight leak in the fuel filler neck. I also replaced the gas cap, but in my owner's manual it says the car will alert you to a gas cap problem by turning on the reserve fuel level light in the gas gauge. I dunno. Hope you get this worked out.
02-23-2009, 05:31 PM
#70
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Thread Starter
I think I already mentioned this, but my 05 C230 had an elusive small evap. leak last year. It took three or four trips to the dealer before it turned out to be a slight leak in the fuel filler neck. I also replaced the gas cap, but in my owner's manual it says the car will alert you to a gas cap problem by turning on the reserve fuel level light in the gas gauge. I dunno. Hope you get this worked out.
02-23-2009, 05:36 PM
#71
MBWorld Fanatic!
I was under warranty, so I don't know how much it would have cost me. It didn't seem to take very long, though. My work-up says they replaced the fuel filler neck. They threw several parts at it, including a charcoal canister and several purge valves in various places before they figured out the real issue. I had the same P0456 code. It also would go away sometimes when the fuel was low.
The only thing is that my car never ran rough because of it. That part doesn't make sense. Also, it was the smoke test that revealed the small leak. If they've already done this to your car and it turned up nothing, maybe it's not the same issue. But I do know the car can notify you about a loose or missing gas cap with the low fuel light. I've had that happen.
The only thing is that my car never ran rough because of it. That part doesn't make sense. Also, it was the smoke test that revealed the small leak. If they've already done this to your car and it turned up nothing, maybe it's not the same issue. But I do know the car can notify you about a loose or missing gas cap with the low fuel light. I've had that happen.
02-23-2009, 05:38 PM
#72
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Thread Starter
I was under warranty, so I don't know how much it would have cost me. It didn't seem to take very long, though. My work-up says they replaced the fuel filler neck. They threw several parts at it, including a charcoal canister and several purge valves in various places before they figured out the real issue. I had the same P0456 code. It also would go away sometimes when the fuel was low.
The only thing is that my car never ran rough because of it. That part doesn't make sense. Also, it was the smoke test that revealed the small leak. If they've already done this to your car and it turned up nothing, maybe it's not the same issue. But I do know the car can notify you about a loose or missing gas cap with the low fuel light. I've had that happen.
The only thing is that my car never ran rough because of it. That part doesn't make sense. Also, it was the smoke test that revealed the small leak. If they've already done this to your car and it turned up nothing, maybe it's not the same issue. But I do know the car can notify you about a loose or missing gas cap with the low fuel light. I've had that happen.
02-23-2009, 05:41 PM
#73
Super Moderator
New inlet pipe - I thought only Ford Pinto's did that after a bump! - the reserve fuel light comes on if you have not put the cap on properly - That is a major evapourative leak!
02-23-2009, 05:48 PM
#74
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