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Discussion Starter #21
I hate to say I told you so.... if the engine runs, it’s not the fuel pumps. Stop throwing parts at it.

X2 as above. Follow the source of the problem back. If you don’t know how to test it or use a meter, ask. No one here will flame you for asking a basic question, or wanting to trouble shoot properly.
OK Dude99 I am game:). I have a basic volt meter with continuity, voltage and OHM functions. I also have a Ancel PB100 that can provide power from the battery directly to a component and test the same things. The car car has an eight socket test connector. Where do i start etc? THANKS:)
 

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I think gozody already agreed back in post 11 that post 10 is where you want to start. It will not end there, that is just the beginning, perhaps it will lead us down the correct path.

- Sinan
 

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Listen to dolucasi, read his post #10
 

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Discussion Starter #24
I think gozody already agreed back in post 11 that post 10 is where you want to start. It will not end there, that is just the beginning, perhaps it will lead us down the correct path.

- Sinan
Car doesn't idle so can't do #10 post. I did measure the voltage at the IACV (two pin plug) with the ignition on and car not running and got 1.95 Volts. Post #16 seems promising but i don't know how to do any of what is described. I did get it started a few times but its tough and abusive on the starter so no longer an option. Thanks for the input:)
 

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Just out of curiosity, and this is outside of the next tests that I'm sure dolucasi will be along shortly with (the idle control system isn'y my strong suit so I'll let others try before I jump in), but if you start it, and keep it running using the accelerator, when it reaches operating temperature, ~80*C, will it idle then?
 

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Discussion Starter #26
Car doesn't idle so can't do #10 post. I did measure the voltage at the IACV (two pin plug) with the ignition on and car not running and got 1.95 Volts. Post #16 seems promising but i don't know how to do any of what is described. I did get it started a few times but its tough and abusive on the starter so no longer an option. Thanks for the input:)
I also tested for fault codes at the 8 socket diagnostic connector. Port 3 is for the CIS-E and got only one flash which indicates "No Fault Found". None of the other ports seems to have anything to do with areas that need to looked at. Where is the ECU located and can i test it with the stuff I have. A volt,continuity,ohm meter and a Ancel PB100 that does the same and can supply 12v dc power directly to a part.
 

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Discussion Starter #27
I also tested for fault codes at the 8 socket diagnostic connector. Port 3 is for the CIS-E and got only one flash which indicates "No Fault Found". None of the other ports seems to have anything to do with areas that need to looked at. Where is the ECU located and can i test it with the stuff I have. A volt,continuity,ohm meter and a Ancel PB100 that does the same and can supply 12v dc power directly to a part.
Dude99- No it wouldn't idle even after it got up to temp.
 

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If you unhook the house going to the engine from the ice, it should run up to 1500rpm and idle there. Does it do this?
 

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Discussion Starter #29
I tried to start with icav disconnected and it would not start. I couldn't pull icav even when it did stsrt as no one here to keep revs up while I tried to pull plug.
 

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Hmmm. It does not start with the IACV disconnected. With 0 voltage at that connector (disconnected) the car should idle at 1100rpm when warm. Have you tried this with a warm engine? I mean start it with it connected, keep it going till pressing the throttle. Then try the exteriments suggested.

If you have a remote starter (bosch ones at O'riely etc are only $12, you can start your car while under the hood and assist the throttle to keep it going and with your free hand and measure the IACV voltage. 1.25V or so is when the orifice in the IACV is actually nearly closed (anywhere from 1.5V - 2V really, depends on the unit). So I'm surprized it sits there before cranking.

I do not know what the voltage should be with the ignition on engine not running. I can measure mine to see.
 

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A momentary switch across the starter solenoid would also crank it while under the hood.
 

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The Bosch remote starter is pretty much that, a momentary switch that is connected between that battery plus terminal and that dongle that is next to the brake booster. Comes in handy with a lot of engine work, compression tests, etc. Worth all of that $12.
 

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Discussion Starter #33
Thanks for the remote starter info. When I was first dealing with this issue I could start it with the pedal to the floor after long cranking of starter. Yesterday when I tried this there was definitely smoke and the bad smell of an electrical failure. I am trying to be positive and hope it came from the starter but I doubt it. Car still cranks but can't start no matter what I do. Tried again this morning and it started with pedal to floor and careful feathering but still won't idle. Thanks for taking the time and effort to measure yours :). I'll wait to hear from you before trying anything else.
 

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Discussion Starter #34
Good Morning Dolucasi:)
Thanks to the east coast / west coast time difference I was able to go to Autozone and buy the remote starter this morning. Went to hook it up and of course ran into a problem. There is little access to the solenoid on a 4matic. I followed the wires and the larger one goes directly to the positive battery post. The smaller brown with stripe seems to go with some other wires to a junction box on the left side of the engine bay by the brake fluid reservoir. It is easily accessible and seems to provide for back probes while the plug is in the junction box. Below are pics as best I could get. I can't find a wiring diagram that shows this stuff. Is there a way to attach the remote starter using this junction box? Thanks again, G:)
2602177
2602178
 

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My dongle ('89) is somewhat different than yours. It is circular and only has one wire. That is the "hot" that is needed to power up the signal. Perhaps members that are familiar with your year model can help, however your last description of the state of the car changes things. You do not have an "idle" problem like you mentioned before. You have an out right car not "running" problem. Does not even want to start. So I would not diagnose things from the IACV point of view.

These cars are made to run even without an ECU. That is why Mercedes kept using them way past the time of electronic fuel injection systems dawning.

My advice now would be to stop chasing down lambda control part of the emissions system.
If you disconnect the EHA valve and the IACV valve, your car should start and run. Basically the emissions control is out of the picture now. If it does not easily start (well cold start maybe a little difficult if the cold start valve is not operating but after a few seconds of cranking that should be out of the way) and idle at 1100rpm then.....

So it is not starting then, I would start questioning ignition components. Starting from the EZL on down the line.
Did you say you already checked out ignition after the incident?

BTW if you disconnect EHA and IACV the ECU may throw a "check engine" light. Ignore that, that is just saying the ECU can not control the lambda any longer. Not your problem at the moment.
 

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Discussion Starter #36
Now I am confused as the car does run. Sorry if I misled you somehow. It was hard to start so I stopped trying. Then I said fuck it and cranked a little longer, pedal to the floor, and feathering once it caught I got it to start this morning with the same old idle issue. Help!
 

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OK. But after it starts, does it run normally? You said your are having to keep the throttle going. So did you disconnect the IACV connector and perhaps the EHA valve connector. If so did it keep running (idling) without these connected and you not pushing the throttle? Basically, at this point, emission control is doing nothing electronically. Everything is mechanically controlled. So if you have fuel pressure at the FD, car should idle by itself but on the high side (over 1000 rpm). If you have not tried this, try this first.

How do we know your ignition is in working order at this point? Have you put in a glow light that shows strong spark, have you put a timing strobe light to make sure timing is good (10 degree BTDC ~ 700 rpm, more like 30 degree btdc at high rpm, like 3000).

In any case, perhaps tell us what diagnostics you have done to prove the ignition is in order. BTW, I do not mean what components you have placed. That could help eliminate culprits but unless you replaced everything it is difficult to pinpoint.
 

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Discussion Starter #38
Won't start with iavc disconnectrd. Haven't disconnected eha. Ignition is fine. You can put this to bed. As I said to Kevin I am over it. Posted for sale this am. Thanks for all your time and effort. Good luck with your projects:).
 

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Well, sorry we could not help you. If you were confident with your ignition and we all know that the ECU is not even needed to start a car and keep it idling, your last issue was fuel related. Not sure if you had already checked out your system fuel pressure and make sure the specified pressure is applied to the system during cranking.

We tried .....
 

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Discussion Starter #40
Well, sorry we could not help you. If you were confident with your ignition and we all know that the ECU is not even needed to start a car and keep it idling, your last issue was fuel related. Not sure if you had already checked out your system fuel pressure and make sure the specified pressure is applied to the system during cranking.

We tried .....
Thanks. I haven't completely given up. Cold, I disconnected the IACV and EHA plugs and the car started right up but I could not get the rev above 1,000rpm. At the same time it would not idle either. I warmed it up and tried start with IACV unplugged. Wouldn't even crank properly, sounded like gasping for air or something. Did same with just EHA unplugged and same sick sound and no real cranking. A real brain teaser. When it started cold with both plugged in I could drive it using the brake while keeping revs above 1,000 rpm with gas pedal. Not safe or good for he car. Any new ideas? Thanks:).
 
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