starting issues
02-10-2010, 01:17 PM
#1
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starting issues
I've been having an intermittent starting problem, but it's been happening more often lately.
On starting, engine cranks without a problem, but it sometimes (and now more frequently) takes longer to fire. Used to be I would just turn the key and it would start on its own, right away. Now, sometimes it takes a few seconds before it fires up, and I've taken to holding the key in the starting position.
The issue is not consistent. Sometimes I can leave it overnight and it will fire up no problem, but sometimes not. Sometimes I leave it for an hour and it has the issue, sometimes not. It will not have the issue if I just leave the car off for a few minutes (ie, run into the store, come out 10 minutes later).
Swapped out the CPS, same deal. Previous owner gave me an extra MAF sensor, swapped that in and no change. Put in a fuel filter the other night, problem seems to persist.
Fuel pump? Fuel pressure regulator? Can get a fuel pump locally for about C$310, but I see them on eBay from US$70. Don't want to go splashing out $300 if I don't need to, as I think I will have to do my brakes soon too, and everyone knows how pricey those parts are.
Any suggestions appreciated! AUSMBTECH recommended that I check fuel pressure, but I still need to figure out precisely how to do it, as I don't have a gauge handy that isn't a permanent type. I suspect one can screw on a gauge with an appropriate adaptor to the pressure relief valve on the rail?
AUSMBTECH also told me that it was likely not the ring gear lube issue, as that is supposed to be only for certain circumstances, ie. car tries to start, but then fails, and the tach jumps to 2000rpm, etc. The local dealer has the lube in stock, but it's like $150. They were deaf to my pleas to 'borrow' a palmful from any open tin they may have.
As an aside, when I swapped in the unused, but sitting in a box for a while MAF, after 15 minutes of driving, the car was very unhappy and didn't want to rev. Opened the hood and pushed things around a bit, and the driveability problem disappeared. But a few days later I got the P0170 and P0173 codes. And I noticed the gear shifts were sometimes more abrupt. Cleared the codes, swapped in the old MAF, which has Bosch part number and Benz star logo on it, and the codes haven't come up again, and the shifts are silky smooth again. Weirdness. My mechanic friend did tell me that wonky MAFs could affect shift quality, but didn't elaborate. Have to pick is brain again. Haven't tried cleaning the MAF, as the original one is good for now, but I'll try that in the future.
On starting, engine cranks without a problem, but it sometimes (and now more frequently) takes longer to fire. Used to be I would just turn the key and it would start on its own, right away. Now, sometimes it takes a few seconds before it fires up, and I've taken to holding the key in the starting position.
The issue is not consistent. Sometimes I can leave it overnight and it will fire up no problem, but sometimes not. Sometimes I leave it for an hour and it has the issue, sometimes not. It will not have the issue if I just leave the car off for a few minutes (ie, run into the store, come out 10 minutes later).
Swapped out the CPS, same deal. Previous owner gave me an extra MAF sensor, swapped that in and no change. Put in a fuel filter the other night, problem seems to persist.
Fuel pump? Fuel pressure regulator? Can get a fuel pump locally for about C$310, but I see them on eBay from US$70. Don't want to go splashing out $300 if I don't need to, as I think I will have to do my brakes soon too, and everyone knows how pricey those parts are.
Any suggestions appreciated! AUSMBTECH recommended that I check fuel pressure, but I still need to figure out precisely how to do it, as I don't have a gauge handy that isn't a permanent type. I suspect one can screw on a gauge with an appropriate adaptor to the pressure relief valve on the rail?
AUSMBTECH also told me that it was likely not the ring gear lube issue, as that is supposed to be only for certain circumstances, ie. car tries to start, but then fails, and the tach jumps to 2000rpm, etc. The local dealer has the lube in stock, but it's like $150. They were deaf to my pleas to 'borrow' a palmful from any open tin they may have.
As an aside, when I swapped in the unused, but sitting in a box for a while MAF, after 15 minutes of driving, the car was very unhappy and didn't want to rev. Opened the hood and pushed things around a bit, and the driveability problem disappeared. But a few days later I got the P0170 and P0173 codes. And I noticed the gear shifts were sometimes more abrupt. Cleared the codes, swapped in the old MAF, which has Bosch part number and Benz star logo on it, and the codes haven't come up again, and the shifts are silky smooth again. Weirdness. My mechanic friend did tell me that wonky MAFs could affect shift quality, but didn't elaborate. Have to pick is brain again. Haven't tried cleaning the MAF, as the original one is good for now, but I'll try that in the future.
02-10-2010, 01:40 PM
#2
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83 500SEC, 87 300D, 02 C32(x2), 02 C320T (x2), 03 C320T4, 03 C320T, 03 E55, 05 E320CDI, 06 E320CDI
Mine has been intermittently starting and dying out immediatly, sometimes 2x before finally staying running, always usually with an extended cranking time, I know I need a cam pos sensor still and am hoping that will take care of it.
02-11-2010, 05:08 PM
#3
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Borrowed a pressure gauge with a proper R12 connector (same as on some AC components) and screwed it onto the fuel rail. Found pressure when running was about 55 psi, but once engine off, pressure dropped almost immediately to 10 psi (within about 10-20 seconds). A few more minutes after that, pressure down to 5 psi, and a few more minutes and it was barely registering.
Ausmbtech has been helpful and suggested the fuel pump as the likely problem. Have thus bit the bullet and ordered an OE replacement by Meyle. Should have it tomorrow, into the car over the weekend.
The problem isn't really intermittent anymore, but more of a frequent occurrence.
Joy of joys...full brake job is likely next....should be able to get front rotors for C$300 each, this is the price my mechanic friend would get, so it's a cash price for me. Dealer price is $405 each! Zimmerman rears are more reasonable, $62 each. But going to double check rotor life, see if they are within tolerances. If so, then will just do pads I think.
Ausmbtech has been helpful and suggested the fuel pump as the likely problem. Have thus bit the bullet and ordered an OE replacement by Meyle. Should have it tomorrow, into the car over the weekend.
The problem isn't really intermittent anymore, but more of a frequent occurrence.
Joy of joys...full brake job is likely next....should be able to get front rotors for C$300 each, this is the price my mechanic friend would get, so it's a cash price for me. Dealer price is $405 each! Zimmerman rears are more reasonable, $62 each. But going to double check rotor life, see if they are within tolerances. If so, then will just do pads I think.
02-11-2010, 05:57 PM
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83 500SEC, 87 300D, 02 C32(x2), 02 C320T (x2), 03 C320T4, 03 C320T, 03 E55, 05 E320CDI, 06 E320CDI
Let us know how that pump holds up. I try to avoid Meyle parts whenever I can, just have had too many failures with their junk.
02-17-2010, 10:47 PM
#5
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Thread Starter
Finally got time to sort out the fuel pump yesterday. Was hoping to do it over the weekend, but got stuck with the flu!
Pressure on starting is good 55 psi, takes about 5 minutes to drop to 30ish psi, and after 20 minutes, down to 10 psi. But holds at 10 psi.
Driving around today, more stopping and starting than my usual commute, and no worries.
Problem seems to be solved! Thanks to Ausmbtech for the assistance!
Pressure on starting is good 55 psi, takes about 5 minutes to drop to 30ish psi, and after 20 minutes, down to 10 psi. But holds at 10 psi.
Driving around today, more stopping and starting than my usual commute, and no worries.
Problem seems to be solved! Thanks to Ausmbtech for the assistance!
