misfire
#1
MBWorld Fanatic!
Thread Starter
misfire
I started my car last night and it turned of after maybe 1 or two seconds
I tried to start it again and it didn't work, third time, it started fine
next time I tried it also started fine
could this be my valve cover gasket? I replaced it maybe 2 months ago but I noticed it was still leaking, my friend did it for me
also my engine temperature goes up to 95 and a bit over sometimes, I know this is a bit higher than normal, what could be causing this? I changed my oil yesterday hoping that was it but it wasnt
I tried to start it again and it didn't work, third time, it started fine
next time I tried it also started fine
could this be my valve cover gasket? I replaced it maybe 2 months ago but I noticed it was still leaking, my friend did it for me
also my engine temperature goes up to 95 and a bit over sometimes, I know this is a bit higher than normal, what could be causing this? I changed my oil yesterday hoping that was it but it wasnt
#3
MBWorld Fanatic!
I believe it's highly unlikely that your valve cover gasket could cause a misfire. It would have to dump enough oil to short the plug wires. What you described doesn't sound like a single misfire. The car turned off. A misfire is usually one or two cylinders. A misfire causes the engine to shake, but it still runs. I'd buy a CPS. That will cause the car to turn off and hesitate at turning back on. A CPS is about $55 @ Autohaus AZ, $85 @ a dealer with the MBCA discount, and $120 for people who insist on paying retail.
Oil won't cause a car to run warm. If it does, the car is seriously low on oil. It's 80 degrees today in SoCal, but the rest of the country is in winter. Your car shouldn't run warm if you're a "rest of the country" guy. If it's original, I'd look at replacing the thermostat. Other things to check:
Oil won't cause a car to run warm. If it does, the car is seriously low on oil. It's 80 degrees today in SoCal, but the rest of the country is in winter. Your car shouldn't run warm if you're a "rest of the country" guy. If it's original, I'd look at replacing the thermostat. Other things to check:
- Is the coolant level normal?
- Is the coolant due to be changed?
- If the car runs warm while on the freeway, the radiator may be obstructed.
- If the car runs warm in bumper to bumper the fan clutch may be bad.
- If you have original hoses, when the go bad, they collapse under vacuum and don't supply adequate flow.
#5
MBWorld Fanatic!
Thread Starter
sry was gonna reply to this but I forgot
no starting problems since then
its been cold lately and the temperature has been sitting at maybe 85
when the sun is out, it goes up to 95 after a long drive in traffic, its fine on the freeway
haven't done anything to the car since I bought it, you think a new water pump would reduce the temperature? I think they have an updated version of it for our cars
coolant is topped of btw
no starting problems since then
its been cold lately and the temperature has been sitting at maybe 85
when the sun is out, it goes up to 95 after a long drive in traffic, its fine on the freeway
haven't done anything to the car since I bought it, you think a new water pump would reduce the temperature? I think they have an updated version of it for our cars
coolant is topped of btw
#6
Super Member
sry was gonna reply to this but I forgot
no starting problems since then
its been cold lately and the temperature has been sitting at maybe 85
when the sun is out, it goes up to 95 after a long drive in traffic, its fine on the freeway
haven't done anything to the car since I bought it, you think a new water pump would reduce the temperature? I think they have an updated version of it for our cars
coolant is topped of btw
no starting problems since then
its been cold lately and the temperature has been sitting at maybe 85
when the sun is out, it goes up to 95 after a long drive in traffic, its fine on the freeway
haven't done anything to the car since I bought it, you think a new water pump would reduce the temperature? I think they have an updated version of it for our cars
coolant is topped of btw
#7
MBWorld Fanatic!
Thread Starter
Ive only had the car for maybe 3 months
I think ill flush the coolant first and see how that goes
I wouldnt know about the thermostat
I think ill flush the coolant first and see how that goes
I wouldnt know about the thermostat
Last edited by PJmak; 03-04-2009 at 12:03 AM.
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#8
Super Member
#9
MBWorld Fanatic!
I wouldn't change the pump. When water pumps go out, it's usually the shaft bearing seal. When it's the seal, they're wet around the weep hole. That doesn't impact the pump's ability to move coolant, so it doesn’t affect temperatures until the coolant level is low. I've heard of the impeller corroding away to nothing, but never personally seen it. An impeller that's sufficiently corroded could cause a car to run warm, but I doubt that's it.
This is how I'd diagnose it. After the car is completely warmed up but not running, I'd grab the fan and see how much effort is required to move it. If it freewheels, the fan clutch is toast. Some people will say to try and stop the fan while the engine is moving. They're either joking or don't value their fingers as much as I do mine. Next, I'd take my infrared pyrometer and use it to see if the radiator has a cold spot. If it does, it's clogged. The solutions are to rod it out or replace it. I'd replace it. A new one at a dealer is about $210 (w/MBCA discount). If the radiator is good, the IR pyrometer can be used to tell of the thermostat is any good. The OEM thermostat is an 87C unit. 87C is when it starts to open, so 95 isn't that high. If everything checks out, I'd also use the HVAC controller to check the temperature – just in case the gauge is a little off. That, and I'm easily bored in bumper to bumper.
I hope that helps.
This is how I'd diagnose it. After the car is completely warmed up but not running, I'd grab the fan and see how much effort is required to move it. If it freewheels, the fan clutch is toast. Some people will say to try and stop the fan while the engine is moving. They're either joking or don't value their fingers as much as I do mine. Next, I'd take my infrared pyrometer and use it to see if the radiator has a cold spot. If it does, it's clogged. The solutions are to rod it out or replace it. I'd replace it. A new one at a dealer is about $210 (w/MBCA discount). If the radiator is good, the IR pyrometer can be used to tell of the thermostat is any good. The OEM thermostat is an 87C unit. 87C is when it starts to open, so 95 isn't that high. If everything checks out, I'd also use the HVAC controller to check the temperature – just in case the gauge is a little off. That, and I'm easily bored in bumper to bumper.
I hope that helps.
#10
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Join Date: Mar 2006
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1997 C36AMG
dude, ur car is running hot? 85 is a bit high man, mine sits below 80 like 75 at times 70, but damn you gota flush your reservoir and radiator i did that to mine when i got it, and it ran soo much cooler also use the coolant from mercedes (TRUST ME IT'S SOME STRONG *****) it really keeps the car cooler... and make sure your usin 0W40 mobile one...
then again i'm running a cold air intake behind my front bumper most likely why its' running that cold...
#11
MBWorld Fanatic!
Thread Starter
I wouldn't change the pump. When water pumps go out, it's usually the shaft bearing seal. When it's the seal, they're wet around the weep hole. That doesn't impact the pump's ability to move coolant, so it doesn’t affect temperatures until the coolant level is low. I've heard of the impeller corroding away to nothing, but never personally seen it. An impeller that's sufficiently corroded could cause a car to run warm, but I doubt that's it.
This is how I'd diagnose it. After the car is completely warmed up but not running, I'd grab the fan and see how much effort is required to move it. If it freewheels, the fan clutch is toast. Some people will say to try and stop the fan while the engine is moving. They're either joking or don't value their fingers as much as I do mine. Next, I'd take my infrared pyrometer and use it to see if the radiator has a cold spot. If it does, it's clogged. The solutions are to rod it out or replace it. I'd replace it. A new one at a dealer is about $210 (w/MBCA discount). If the radiator is good, the IR pyrometer can be used to tell of the thermostat is any good. The OEM thermostat is an 87C unit. 87C is when it starts to open, so 95 isn't that high. If everything checks out, I'd also use the HVAC controller to check the temperature – just in case the gauge is a little off. That, and I'm easily bored in bumper to bumper.
I hope that helps.
This is how I'd diagnose it. After the car is completely warmed up but not running, I'd grab the fan and see how much effort is required to move it. If it freewheels, the fan clutch is toast. Some people will say to try and stop the fan while the engine is moving. They're either joking or don't value their fingers as much as I do mine. Next, I'd take my infrared pyrometer and use it to see if the radiator has a cold spot. If it does, it's clogged. The solutions are to rod it out or replace it. I'd replace it. A new one at a dealer is about $210 (w/MBCA discount). If the radiator is good, the IR pyrometer can be used to tell of the thermostat is any good. The OEM thermostat is an 87C unit. 87C is when it starts to open, so 95 isn't that high. If everything checks out, I'd also use the HVAC controller to check the temperature – just in case the gauge is a little off. That, and I'm easily bored in bumper to bumper.
I hope that helps.
fan spins slowly when the engine runs so I don't wanna try grabbing it lol
flushed the coolant and replaced the thermostat today
car sits at low 80s when Im driving but If i sit at a light longer than you normally would, the temperature raises up a bit
it went as high as 95, if not even a bit higher today at the light(after I replaced the tstat and did the flush)
#12
Super Member
fan spins slowly when the engine runs so I don't wanna try grabbing it lol
flushed the coolant and replaced the thermostat today
car sits at low 80s when Im driving but If i sit at a light longer than you normally would, the temperature raises up a bit
it went as high as 95, if not even a bit higher today at the light(after I replaced the tstat and did the flush)
flushed the coolant and replaced the thermostat today
car sits at low 80s when Im driving but If i sit at a light longer than you normally would, the temperature raises up a bit
it went as high as 95, if not even a bit higher today at the light(after I replaced the tstat and did the flush)
#13
fan spins slowly when the engine runs so I don't wanna try grabbing it lol
flushed the coolant and replaced the thermostat today
car sits at low 80s when Im driving but If i sit at a light longer than you normally would, the temperature raises up a bit
it went as high as 95, if not even a bit higher today at the light(after I replaced the tstat and did the flush)
flushed the coolant and replaced the thermostat today
car sits at low 80s when Im driving but If i sit at a light longer than you normally would, the temperature raises up a bit
it went as high as 95, if not even a bit higher today at the light(after I replaced the tstat and did the flush)