1988 300TE - Misfires - Where to go now?
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Did you get 9 volts out of the O2 sensor?
You have ruled out vacuum leaks in the past, but you need to revisit that and make sure the leak is not at the end user ( brake booster-vacuum reservoir, Air conditioning controls, fuel tank evaporative system)
From what you have stated it sounds like text book vacuum leak.
You have ruled out vacuum leaks in the past, but you need to revisit that and make sure the leak is not at the end user ( brake booster-vacuum reservoir, Air conditioning controls, fuel tank evaporative system)
From what you have stated it sounds like text book vacuum leak.
I just won a used fuel distributor off a working 1987 300E for $40 and the accompanying eha valve for $20. I think I got that for a hell of a deal! For $60 together, I couldn't pass up the chance so I just bid on them and won.
I have been reading about this Mercedes guy named "Enrique" in South Fernando Valley just north of LA and he has been highly recommended(I read people from texas drive all the way to see him!). I am thinking I might hand the car over to him for a few hours and get him to check things out. I was unhappy with the previous shop I took it to, but apparently this guy is very honest, cheap and has a very good track record. (he also used to drive a 300TE). I think if I give it to him, I will have him run a vacuum test on it because I would trust any person better than myself...I mean with the 0 previous car experience I have, I could make mistakes and missing a vacuum leak would be a pretty large mistake. I am heading up to northern california this weekend, so maybe I can stop by on the way and see what he can do.
I'll give him a call tomorrow, get an estimate and see what he says.
Last edited by ps2cho; Nov 26, 2007 at 02:31 AM.
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Have you personally used this Coastline Auto? If so, how was your experience?
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lots of cars
Well, I haven't used them because i've never really had to. I was quoted reasonable rates for some work i needed but I ended up doing it myself. I've been to the shop and i've seen the work they've done. This guy is even on the forums and goes by E4///Turbo. He has a e220 grey market convertible with a turbo. He knows a lot about the w124.
You can also call BOB @
(562) 432-7379
Werkstat West. 1430 West Pacific Coast Highway, Long Beach, CA 90810
This was my mechanic for years but we had a little disagreement. He's a good mechanic with good rates so i'll still recommend him.
You can also call BOB @
(562) 432-7379
Werkstat West. 1430 West Pacific Coast Highway, Long Beach, CA 90810
This was my mechanic for years but we had a little disagreement. He's a good mechanic with good rates so i'll still recommend him.
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Here's an interesting link that might be useful:
http://www.landiss.com/mixture.htm
I'm also in the process of tuning up my car, recently replaced a missing O2 sensor, and yesterday finally got the system into closed loop mode by adjusting the idle fuel mixture ratio. Problem is the "Check Engine" lamp is still on all the time, even after trying to reset the CIS-E by disconnecting the battery for 30 minutes.
Hope you can fix the misfiring problem of your engine.
-Alex
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O2 sensor voltage output (black lead to ground) range should be between 0.1 and 0.9VDC. The richer the mixture, the higher the output voltage. You probably where reading voltage on the wrong scale, so those 9V you reported where actually 0.9V. That BTW confirms an overly rich mixture condition, or a badly clogged sensor. Normally the voltage should be jumping around a bit between 0.4 to 0.7V (average of ~0.5V) that indicates that the system is under closed loop control, which basically means the CIS-E controller is continuously compensating the fuel mixture ratio between slightly rich and slightly lean.
Here's an interesting link that might be useful:
http://www.landiss.com/mixture.htm
I'm also in the process of tuning up my car, recently replaced a missing O2 sensor, and yesterday finally got the system into closed loop mode by adjusting the idle fuel mixture ratio. Problem is the "Check Engine" lamp is still on all the time, even after trying to reset the CIS-E by disconnecting the battery for 30 minutes.
Hope you can fix the misfiring problem of your engine.
-Alex
Here's an interesting link that might be useful:
http://www.landiss.com/mixture.htm
I'm also in the process of tuning up my car, recently replaced a missing O2 sensor, and yesterday finally got the system into closed loop mode by adjusting the idle fuel mixture ratio. Problem is the "Check Engine" lamp is still on all the time, even after trying to reset the CIS-E by disconnecting the battery for 30 minutes.
Hope you can fix the misfiring problem of your engine.
-Alex
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Temperature sensor or O2 sensor? If you meant temperature sensor, neither I, nor the previous owners to my knowledge have touched it.
When you say "limp home mode" do you mean like, working but not working correctly?
And man I really appreciate your help with everything. It means a lot to me...and hopefully I will get this fixed soon. I will for sure post back with when I get it fixed.
Oh and as for the Rotor and Cap....the previous owners said they replaced it (no receipt though)...but is there anyways to actually test that it is ok, or do you just clean it/replace? It looks like new its $70 for both together.
When you say "limp home mode" do you mean like, working but not working correctly?
And man I really appreciate your help with everything. It means a lot to me...and hopefully I will get this fixed soon. I will for sure post back with when I get it fixed.
Oh and as for the Rotor and Cap....the previous owners said they replaced it (no receipt though)...but is there anyways to actually test that it is ok, or do you just clean it/replace? It looks like new its $70 for both together.
Last edited by ps2cho; Nov 26, 2007 at 04:45 PM.
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From: Long Beach, Ca
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Yes, working but only on the mechanical side and the electronics not working. The temp sensor tells the computer weather your car is hot or cold and will adjust the mixture on start up and control the EHA valve.
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I was just taking a look at my ICV and the hoses don't look as good as I think they should be. I can see the signs of the plastic cracking. They are not hard, but they have sort of small "slashes/cuts" where they join the ICV. No noticable holes, but some wear. Do these hoses need to be a vacuum? What do you think?
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The 300E does not really use a "limp home" condition, as this refers to a mode of operation with drastically reduced power output from the engine (hence the "limp" part of the name), and on some models the transmission stays on 2nd gear to limit speed. This mode enables you to get home or to the dealer, while limiting possible additional damage to the car and/or unsafe driving conditions, and has mainly been implemented in newer models then our 300E's. It kicks in when certain faults are detected, and is not limited in response just to the fuel delivery system faults. When this condition happens, the faults need to be cleared with a special fixture, and the cause for them corrected before the car is once again drivable in a normal way.
Hope this is helpful.
-Alex
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1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
I was just taking a look at my ICV and the hoses don't look as good as I think they should be. I can see the signs of the plastic cracking. They are not hard, but they have sort of small "slashes/cuts" where they join the ICV. No noticable holes, but some wear. Do these hoses need to be a vacuum? What do you think?
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It means the fuel management system is operating on "open loop" mode, possibly because one or more input signals from sensors or otherwise are missing or out of range. Fortunately the mechanical part of the fuel distribution system is accurate enough to function properly without the intervention of the electronic controller. This enables you to continue to use the car in a almost normal way, but only at somewhat lower then optimum settings that will make your mixture rich, and mainly hurt your fuel economy, higher emissions, and will also somewhat affect the power output of the engine. Idle smoothness may also be affected.
The 300E does not really use a "limp home" condition, as this refers to a mode of operation with drastically reduced power output from the engine (hence the "limp" part of the name), and on some models the transmission stays on 2nd gear to limit speed. This mode enables you to get home or to the dealer, while limiting possible additional damage to the car and/or unsafe driving conditions, and has mainly been implemented in newer models then our 300E's. It kicks in when certain faults are detected, and is not limited in response just to the fuel delivery system faults. When this condition happens, the faults need to be cleared with a special fixture, and the cause for them corrected before the car is once again drivable in a normal way.
Hope this is helpful.
-Alex
The 300E does not really use a "limp home" condition, as this refers to a mode of operation with drastically reduced power output from the engine (hence the "limp" part of the name), and on some models the transmission stays on 2nd gear to limit speed. This mode enables you to get home or to the dealer, while limiting possible additional damage to the car and/or unsafe driving conditions, and has mainly been implemented in newer models then our 300E's. It kicks in when certain faults are detected, and is not limited in response just to the fuel delivery system faults. When this condition happens, the faults need to be cleared with a special fixture, and the cause for them corrected before the car is once again drivable in a normal way.
Hope this is helpful.
-Alex
Ok. I will get these hoses replaced.
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I hope people will start to listen to me now lol....Glad you figured it out...
Once you get the ebay fuel distributor and the EHA valve keep us updated..
** make sure you don't damage the O-Ring on the old fuel distributor when you remove it because you will probably need it for the new one**
Also, go back to the list of things we said you need to do...
Once you get the ebay fuel distributor and the EHA valve keep us updated..
** make sure you don't damage the O-Ring on the old fuel distributor when you remove it because you will probably need it for the new one**
Also, go back to the list of things we said you need to do...
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I hope people will start to listen to me now lol....Glad you figured it out...
Once you get the ebay fuel distributor and the EHA valve keep us updated..
** make sure you don't damage the O-Ring on the old fuel distributor when you remove it because you will probably need it for the new one**
Also, go back to the list of things we said you need to do...
Once you get the ebay fuel distributor and the EHA valve keep us updated..
** make sure you don't damage the O-Ring on the old fuel distributor when you remove it because you will probably need it for the new one**
Also, go back to the list of things we said you need to do...
The only thing that I haven't done from that list is the fuel pressure, but when I put the fuel distributor in, if the misfire is still there, next thing will be the fuel pressure. But for a $30 used fuel distributor....its worth a try
Thanks for the information about the O-Ring, I will make sure I am careful.
Fingers crossed that my problem will be solved!
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
Just got back from my 1000 mile round trip this weekend. The car was absolutely amazing the whole drive once Enrique adjusted the mixture correctly. As smooth(acceleration and ride!) as its ever been. The car is a dream to drive when its not at a stop light
The only thing that I haven't done from that list is the fuel pressure, but when I put the fuel distributor in, if the misfire is still there, next thing will be the fuel pressure. But for a $30 used fuel distributor....its worth a try
Thanks for the information about the O-Ring, I will make sure I am careful.
Fingers crossed that my problem will be solved!
The only thing that I haven't done from that list is the fuel pressure, but when I put the fuel distributor in, if the misfire is still there, next thing will be the fuel pressure. But for a $30 used fuel distributor....its worth a try
Thanks for the information about the O-Ring, I will make sure I am careful.
Fingers crossed that my problem will be solved!
Keep us posted
MBWorld Fanatic!
Joined: Oct 2006
Posts: 3,642
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
O2 sensor voltage output (black lead to ground) range should be between 0.1 and 0.9VDC. The richer the mixture, the higher the output voltage. You probably where reading voltage on the wrong scale, so those 9V you reported where actually 0.9V. That BTW confirms an overly rich mixture condition, or a badly clogged sensor. Normally the voltage should be jumping around a bit between 0.4 to 0.7V (average of ~0.5V) that indicates that the system is under closed loop control, which basically means the CIS-E controller is continuously compensating the fuel mixture ratio between slightly rich and slightly lean.
Here's an interesting link that might be useful:
http://www.landiss.com/mixture.htm
I'm also in the process of tuning up my car, recently replaced a missing O2 sensor, and yesterday finally got the system into closed loop mode by adjusting the idle fuel mixture ratio. Problem is the "Check Engine" lamp is still on all the time, even after trying to reset the CIS-E by disconnecting the battery for 30 minutes.
Hope you can fix the misfiring problem of your engine.
-Alex
Here's an interesting link that might be useful:
http://www.landiss.com/mixture.htm
I'm also in the process of tuning up my car, recently replaced a missing O2 sensor, and yesterday finally got the system into closed loop mode by adjusting the idle fuel mixture ratio. Problem is the "Check Engine" lamp is still on all the time, even after trying to reset the CIS-E by disconnecting the battery for 30 minutes.
Hope you can fix the misfiring problem of your engine.
-Alex
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Hmmm... I just realized that I might have the wrong bulb in the Check Engine indicator position. I now remember there was another empty bulb holder, the SRS indicator, which I recall used to stay on all the time too (that's another fault I need to track down). Will have to double check the color of the wires on the bulb holder I'm currently using to make sure I have the right one. According to the wiring schematic the O2 indicator should be the one with the grey/green and black/violet wires, while the SRS uses brown/red and brown wires.
BTW, does anybody know where to find the schematic of the CIS-E module, I mean of the internal circuit board with all the electronics, not the external connections to it. Those I have on the service CD.
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Today I checked the wire color of the O2 light bulb and indeed I was using the wrong socket. Now the bulb comes on when the key is turned to the RUN position, along with all others, but extinguishes as soon as the engine is started.
Problem solved!
Problem solved!
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Wow fast shipping! Got the whole unit today! It's pretty dirty and coated in oil (pictures did show that) so I need to clean it up first. I have the whole unit which the fuel distributor attaches too...but I only need the FD.
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Ok guys I'm back!
Been really busy with finals at school and was waiting for my dad to help me put in this fuel distributor.
We put it in successfully, but problem is not solved
At first it was starting really horrible. Idling at 500 caused it to really shudder....but then we adjusted the fuel mixture and it feels about the same now.
Now, just to keep you up to date, this was a used fuel distributor, but the likelihood that I obtained one that feels exactly the same must be pretty small...There's no difference at all. (Oh forgot to mention, this actually solved my premature shifting in 1st gear! YES! Wasn't expecting that to happen, but it seems to be going all the way to the redline now instead of shifting prematurely at 3-4k rpm)
So back to the game plan now then. Next would be the Fuel Pressure Regulator correct?
Oh another question I need to ask: When the multimeter is connected using the ground wire, is the % it reads rich or lean? When it shows 45%, is that 45% rich or 45% lean?
Thanks guys!
Been really busy with finals at school and was waiting for my dad to help me put in this fuel distributor.
We put it in successfully, but problem is not solved
At first it was starting really horrible. Idling at 500 caused it to really shudder....but then we adjusted the fuel mixture and it feels about the same now.
Now, just to keep you up to date, this was a used fuel distributor, but the likelihood that I obtained one that feels exactly the same must be pretty small...There's no difference at all. (Oh forgot to mention, this actually solved my premature shifting in 1st gear! YES! Wasn't expecting that to happen, but it seems to be going all the way to the redline now instead of shifting prematurely at 3-4k rpm)
So back to the game plan now then. Next would be the Fuel Pressure Regulator correct?
Oh another question I need to ask: When the multimeter is connected using the ground wire, is the % it reads rich or lean? When it shows 45%, is that 45% rich or 45% lean?
Thanks guys!
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Bumping the thread with some new information I just learned...
I always believed that the previous owners replaced the Distributor+Cap, but apparantly they did not, only cleaned it!
This is what I am thinking:
When I very first replaced the ignition leads, the intensity of the misfire was dramatically reduced which seems very strange to have something like that "kinda" change it, but not fix it.
Does it seem logical that the distributor+cap could the culprit behind the whole thing with this in mind?
Obviously I'm not an expert at cars, but to me, it seems very strange that the ignition leads were contributing to, but were not the problem itself...
What do you guys think?
PS: The car's been awful sluggish in the last few months, 0-60 is around the 12 second mark (I believe it should be closer to 9 seconds).
I always believed that the previous owners replaced the Distributor+Cap, but apparantly they did not, only cleaned it!
This is what I am thinking:
When I very first replaced the ignition leads, the intensity of the misfire was dramatically reduced which seems very strange to have something like that "kinda" change it, but not fix it.
Does it seem logical that the distributor+cap could the culprit behind the whole thing with this in mind?
Obviously I'm not an expert at cars, but to me, it seems very strange that the ignition leads were contributing to, but were not the problem itself...
What do you guys think?
PS: The car's been awful sluggish in the last few months, 0-60 is around the 12 second mark (I believe it should be closer to 9 seconds).
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From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
I would think that a bad distributor cap would look pretty bad. If you have any doubts, replace it. New cap, non-platinum plugs, and wires if you haven't already would be a good idea. How's the coil?
