1988 300TE - Misfires - Where to go now?
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Nope. You may be onto something. If it were me I'd start grabbing things and see what bites. Just make sure you don't stick you hand somewhere that when you jerk it back it cuts you or something. Usually an injury is caused by the reaction to the voltage, not the voltage itself. But you may not want to risk it.
Did you pull the plugs and see which one looks different? Also, if you idle it for 15 minutes and shut it off, one plug should feel a lot cooler than the rest.
Did you pull the plugs and see which one looks different? Also, if you idle it for 15 minutes and shut it off, one plug should feel a lot cooler than the rest.
That seems strange though because the plugs are brand new.
But again, it seems just as strange that when I changed the plugs, it shook less (the intensity)....that, to me is just really strange how it would make it "kinda" better.
I'll do some pulling and see what happens.
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1994 E320 Dragon Wagon
There is a diag. tool where you clip an inductive sensor over one plug wire at a time. It blips a lamp when fired. It's an in-line, screwdriver looking deal called a "spark tester" for under $10. With access to all plug wires, move it along at low idle and look for random fire patterns on troubled cylinder(s).
The indicator lamp may be too weak for viewing in bright daylight. Try it in a garage. Pulling individual plug wires off to test for misfire is often too drastic and the result will be all cylinders have the same effect.
The lamp tool will only verify pulses not the actual voltage hitting the plug. It would help spot a "no fire" condition not weak fire from, for example, a bad wire.
Another tool is an adjustable gap device with a ground clamp attached. It has a tang to snap the plug boot over. Set the gap out a bit from factory and test spark intensity. This may help spot a defect in the coil-plug path.
http://www.toolhawker.net/Ignition-S...tem_32487.aspx
The indicator lamp may be too weak for viewing in bright daylight. Try it in a garage. Pulling individual plug wires off to test for misfire is often too drastic and the result will be all cylinders have the same effect.
The lamp tool will only verify pulses not the actual voltage hitting the plug. It would help spot a "no fire" condition not weak fire from, for example, a bad wire.
Another tool is an adjustable gap device with a ground clamp attached. It has a tang to snap the plug boot over. Set the gap out a bit from factory and test spark intensity. This may help spot a defect in the coil-plug path.
http://www.toolhawker.net/Ignition-S...tem_32487.aspx
Last edited by White_Knuckles; Jan 20, 2008 at 02:58 PM.
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
I have a special spark plug pulling thing that my dad got me (as to not damage the spark plugs before when I had to clean off the oil consumption while I had the leaky stem seal valves)....
That seems strange though because the plugs are brand new.
But again, it seems just as strange that when I changed the plugs, it shook less (the intensity)....that, to me is just really strange how it would make it "kinda" better.
I'll do some pulling and see what happens.
That seems strange though because the plugs are brand new.
But again, it seems just as strange that when I changed the plugs, it shook less (the intensity)....that, to me is just really strange how it would make it "kinda" better.
I'll do some pulling and see what happens.
I would pull them all, line them up in order, and compare. If you can, take a pic and post it.
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I did take some pictures though so you can see how a plug looks (I just pulled #5).
There seems to be weeping around the plug areas, but I don't know if thats anything....Reason I pulled #5 is that the weeping seems to originate from that socket while the other sockets are not covered in the oil.
The clicking is for sure coming from 4,5, or 6, and I used an old plug I had. 4+5 didn't make a difference, and for some reason, I couldn't fit the plug in hole #6 at the distributor cap. It just didn't want to go in and I don't have another plug long enough to reach it. It just wouldn't "pop" into the hole.
How does the plug look though?
Would a good way to test the plugs to test voltage tp each end? What type of voltage should I be seeing?
Last edited by ps2cho; Jan 20, 2008 at 06:37 PM.
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
The plug in the pic looks fine. What do you mean about trying plugs 4 and 5 and #6 not fitting into the hole? I don't understand.
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
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I'll go ahead and run the multimeter through all the wires and I should get the same voltage from all of them. I am pretty sure they will be fine as they are brand new ignition wires.
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From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
No this was using the "test" wire that was previously using. The new ignition wire goes in fine. It just meant I couldn't test #6 cylinder using the old wire.
I'll go ahead and run the multimeter through all the wires and I should get the same voltage from all of them. I am pretty sure they will be fine as they are brand new ignition wires.
I'll go ahead and run the multimeter through all the wires and I should get the same voltage from all of them. I am pretty sure they will be fine as they are brand new ignition wires.
Most multimeters are rated for 600 volts max regarding arching. I write this for the benefit of all.Resistance from end to end of each wire should be about the same on all wires. I don't remember what it should be. You've got to find where that ticking noise is coming from. Did you save all the old wires? If so, I would try swapping out #6 with an old one and test run it. Then move the old wire to #5, etc. There's a remote chance you got a damaged wire in the new set. I have also seen a dead plug come right out of the box and never fire once with no visible defects.
An infrared thermo scanner could also help to see which pipe of the exhaust manifold is cooler. Raytek makes them, but they are usually around $100 or so.
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You mean resistance. If you start the car and try to check voltage (or anything) with the multimeter you are going to get shocked, and probably need a new meter. Also, I've never seen a meter that goes up to 15,000 volts. Most multimeters are rated for 600 volts max regarding arching. I write this for the benefit of all.
Resistance from end to end of each wire should be about the same on all wires. I don't remember what it should be. You've got to find where that ticking noise is coming from. Did you save all the old wires? If so, I would try swapping out #6 with an old one and test run it. Then move the old wire to #5, etc. There's a remote chance you got a damaged wire in the new set. I have also seen a dead plug come right out of the box and never fire once with no visible defects.
An infrared thermo scanner could also help to see which pipe of the exhaust manifold is cooler. Raytek makes them, but they are usually around $100 or so.
Most multimeters are rated for 600 volts max regarding arching. I write this for the benefit of all.Resistance from end to end of each wire should be about the same on all wires. I don't remember what it should be. You've got to find where that ticking noise is coming from. Did you save all the old wires? If so, I would try swapping out #6 with an old one and test run it. Then move the old wire to #5, etc. There's a remote chance you got a damaged wire in the new set. I have also seen a dead plug come right out of the box and never fire once with no visible defects.
An infrared thermo scanner could also help to see which pipe of the exhaust manifold is cooler. Raytek makes them, but they are usually around $100 or so.
And yes that's what I was doing: Using an old wire, BUT that #6 wire from the old set wouldn't clip correctly into the cap.
With each plug removed individually, it misfired alot harder.
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
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This seems to indicate that all 6 plugs are firing at idle, would you agree? As far as ignition is concerned, the cylinder either fires or it doesn't; a weak spark can make a cylinder fire one time around and miss the next time but this would cause a kind of spluttering, just generally crappy sound coming from the exhaust. Does your exhaust sound rough and uneven, or a regular misfire on one cylinder? Going back to the beginning of this thread I was thinking it was uneven, but that's been a while. How about uploading a video to Youtube so we can hear it? That would help a lot!
I'll get a video up as soon as I can find my dads camera.
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http://www.youtube.com/watch?v=vOZQJYyldjA
Well I figured I might as well show you it has no problems accelerating and is smooth. Everything is at idle. Typical that it is not misfiring as hard as other days right now.
Car is very slow though, when I make a right half way through, thats as far as it will go to the floor before the button.....You can see its slow.
Also the economy gauge doesn't seem right either...like how its not on full when I park near the end.
And also you will hear a squeak near the beginning....it just started a few days ago but I think a bushing is worn in the rod. Maybe you can make another suggestion as to what that squeak noise could be? Its for sure coming from the gearbox
Well I figured I might as well show you it has no problems accelerating and is smooth. Everything is at idle. Typical that it is not misfiring as hard as other days right now.
Car is very slow though, when I make a right half way through, thats as far as it will go to the floor before the button.....You can see its slow.
Also the economy gauge doesn't seem right either...like how its not on full when I park near the end.
And also you will hear a squeak near the beginning....it just started a few days ago but I think a bushing is worn in the rod. Maybe you can make another suggestion as to what that squeak noise could be? Its for sure coming from the gearbox
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
http://www.youtube.com/watch?v=vOZQJYyldjA
Well I figured I might as well show you it has no problems accelerating and is smooth. Everything is at idle. Typical that it is not misfiring as hard as other days right now.
Car is very slow though, when I make a right half way through, thats as far as it will go to the floor before the button.....You can see its slow.
Also the economy gauge doesn't seem right either...like how its not on full when I park near the end.
And also you will hear a squeak near the beginning....it just started a few days ago but I think a bushing is worn in the rod. Maybe you can make another suggestion as to what that squeak noise could be? Its for sure coming from the gearbox
Well I figured I might as well show you it has no problems accelerating and is smooth. Everything is at idle. Typical that it is not misfiring as hard as other days right now.
Car is very slow though, when I make a right half way through, thats as far as it will go to the floor before the button.....You can see its slow.
Also the economy gauge doesn't seem right either...like how its not on full when I park near the end.
And also you will hear a squeak near the beginning....it just started a few days ago but I think a bushing is worn in the rod. Maybe you can make another suggestion as to what that squeak noise could be? Its for sure coming from the gearbox
The slightly uneven idle and the fact that the misfire is only present at idle points to an intake leak affecting only one cylinder. You have replaced all 6 injectors? I remember you said all 6 injector seals were replaced but has that been verified? Could one still be leaking? Is the intake manifold gasket damaged or a bolt/nut missing anywhere on the manifold? This is very tricky.
What controls the ignition timing on the M103? If is is not advanced enough it could cause the economy gauge to read low. Also a vacuum leak.
I have no idea about that squeaking. Maybe a warped brake rotor causing a cyclic vibration? But coming from the gearbox?
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Never done it, but I understand you can check for injector seal leaks at idle speed by selectively releasing a little bit of propane gas near each seal while monitoring the voltage of the oxygen sensor and the RPMs. If you notice any changes while applying the propane, that would mean some of the propane is being sucked into the cylinder, presumably through a defective seal, and cause a change in the sensor voltage and/or RPMs.
Some people just use a can of WD40 with the fine applicator tube instead of propane, but I think that way one might create future problems as the rubber of the seals doesn't like the WD40, which may cause it to slowly deteriorate over time.
Regarding the squeak, since it can be heard quite clearly inside the cabin, it sounds to me as it might be related to the steering wheel shaft being turned?
Last edited by azurite300e; Jan 21, 2008 at 08:43 PM.
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Its difficult to show the idle like I said, but its worse than the video shows. Best way I can describe it is the car is shivering because its cold or something. Its a fast paced rumble.
And Injectors+Seals were replaced by the previous owners as they were trying to fix the problem (I believe I have the receipt somewhere too).
And Injectors+Seals were replaced by the previous owners as they were trying to fix the problem (I believe I have the receipt somewhere too).
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
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I gave Bob a call who's in Long Beach and after speaking to him, I was already impressed by his knowledge of the W124. I will have my fuel pressure regulator with me in the next few days and if that does not fix it, then the car will be with Bob friday morning.
I have not even spent $400 total so far on this misfire, so I don't feel bad throwing parts at it right now. I will have a great base for a long lasting car once this is over with.
I really need to do a leakdown test though. I wonder how much it would cost to just get someone to do it for me?
I have not even spent $400 total so far on this misfire, so I don't feel bad throwing parts at it right now. I will have a great base for a long lasting car once this is over with.
I really need to do a leakdown test though. I wonder how much it would cost to just get someone to do it for me?
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From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
You have a great car. I can't wait to see what Bob has to say. I had a problem just like this with my Volvo turbo years ago but I gave up before throwing much money into it. I took it in to this guy who had his own shop and was known as Omaha's Volvo Guru. He figured it out right away as being a blown intake manifold gasket. I guess that was somewhat common on turbos. He didn't charge very much and it ran perfect after that. I hope yours goes something like that.
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1989300CE(sold),1996Accord,02CBR954
I remember saying something like that....I didnt see any ecessive shaking or misfire.thing sounded pretty smooth to me.
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Ok Fuel pressure regulator in!
After sweating and cursing at a bolt that refused to come undone(in the end I got mad as hell and just kicked the mother...on the ground with a wrench on the bolt and it came undone) and drenched in rain, got the new fuel pressure regulator in and the car seems to be running nicer (can't say 100% because of the non-consistancy of the misfire). The misfire IS still there, I can feel it, but right now it seems smoother. By the end of the day I will be able to confirm if its made any difference.
I am still taking the car to Bob tomorrow for sure. I wanted to get this in before I handed it over to him so its one less thing to think about (I actually got this for free because the guy sent me the wrong part!!)
After sweating and cursing at a bolt that refused to come undone(in the end I got mad as hell and just kicked the mother...on the ground with a wrench on the bolt and it came undone) and drenched in rain, got the new fuel pressure regulator in and the car seems to be running nicer (can't say 100% because of the non-consistancy of the misfire). The misfire IS still there, I can feel it, but right now it seems smoother. By the end of the day I will be able to confirm if its made any difference.
I am still taking the car to Bob tomorrow for sure. I wanted to get this in before I handed it over to him so its one less thing to think about (I actually got this for free because the guy sent me the wrong part!!)
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
Ok Fuel pressure regulator in!
After sweating and cursing at a bolt that refused to come undone(in the end I got mad as hell and just kicked the mother...on the ground with a wrench on the bolt and it came undone) and drenched in rain, got the new fuel pressure regulator in and the car seems to be running nicer (can't say 100% because of the non-consistancy of the misfire). The misfire IS still there, I can feel it, but right now it seems smoother. By the end of the day I will be able to confirm if its made any difference.
I am still taking the car to Bob tomorrow for sure. I wanted to get this in before I handed it over to him so its one less thing to think about (I actually got this for free because the guy sent me the wrong part!!)
After sweating and cursing at a bolt that refused to come undone(in the end I got mad as hell and just kicked the mother...on the ground with a wrench on the bolt and it came undone) and drenched in rain, got the new fuel pressure regulator in and the car seems to be running nicer (can't say 100% because of the non-consistancy of the misfire). The misfire IS still there, I can feel it, but right now it seems smoother. By the end of the day I will be able to confirm if its made any difference.
I am still taking the car to Bob tomorrow for sure. I wanted to get this in before I handed it over to him so its one less thing to think about (I actually got this for free because the guy sent me the wrong part!!)
Your video made me jealous to live in Cali. Looking forward to the update after Bob. Is he a member here?
Last edited by shdoug; Jan 24, 2008 at 09:54 PM.
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There can't be much left now! ECU or fuel pressure problem I guess.
Is the fuel pressure regulated by anything else? Basically what I am saying is, if I replaced the FPR and it made no difference (I can confirm now I have driven it 30miles today so far)....that the fuel pressure is fine? Or are there other problematic places that the fuel pressure can be leaking?
I'll let him do whatever he thinks he should test....This car's constant horrible idle just makes me want a new car....but I know if this can be fixed this car will last a million miles! I take good care of her.
