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79 Case 406
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Discussion Starter #1
Not unimog but maybe you can help.

My old 87 e150 with a 5 liter fuel injected engine, automatic tranny 145K miles is acting up. It has been problem free for years and still runs good until recently.

The symptoms:

Engine briefly cutting out causing van to lurch, happens at low and high speeds. Originally felt like maybe the tranny was right at the shift point and jerking as she auto shifted.
Got worse to the point where now she will stall at inopportune moments like crossing intersections. Up to now she's always started back up but maybe soon she will leave me stranded somewhere.

Could this be a FI problem, fuel filter problem, FI pump problem ?

I know this is not a lot of info to go on but thought I would post it here anyway since there is quite a bit of knowledge on this board.

Thanks, Steve
 

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'78 Mog 416.141 DoKa
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Low and high *speeds* or low and high RPM ?? How much electronics is on a 87 motor ?

Do you have throttle position sensors, road speed sensors, temp sensors all feeding the ECU ?

Is there some sort of pre-OBDII check engine light somewhere ?

Are there failure codes that can be read by a scanner ?

Something tells me 87 is pre-all-that-crap and it's probably something relatively simple that's worn out. Fueling system problems are possible but that would normally manifest itself more at wide open throttle or idle - not steady state partial throttle...
 

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4Sale: 230G, U1200 Ag, 1017A, lots of MB cars, Volvo c303, 416 raildoka, LR D110 TDi
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Steve,

It sounds like you may have a failing ignition control module, they are nortorious on the older fords. The up side to this is that it should be fairly simple to replace (at least on the pickups), and I think they usually run like $30, so it is probably worth a shot if you can't get a better diagnosis. It really doesn't sound like a fuel problem unless there is a short in the injector wiring or a fuel pump relay going bad intermittantly, usually the fuel stuff causes them to run like crap all of the time.

Cheers,
Ben
 

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79 Case 406
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Discussion Starter #4
Keith,

It does not have a tach but it will cut out at freeway cruising speeds and at slow around town speeds. I would guess the rpm at freeway speeds to be about 2500 / 65 mph with an overdrive.

I have no idea if it has the other things you asked about.

It seems to happen more when the engine is lazily humming along than when under big load or accelerating but that could change as it seems to be getting worse. Thanks.

SG

Low and high *speeds* or low and high RPM ?? How much electronics is on a 87 motor ?

Do you have throttle position sensors, road speed sensors, temp sensors all feeding the ECU ?

Is there some sort of pre-OBDII check engine light somewhere ?

Are there failure codes that can be read by a scanner ?

Something tells me 87 is pre-all-that-crap and it's probably something relatively simple that's worn out. Fueling system problems are possible but that would normally manifest itself more at wide open throttle or idle - not steady state partial throttle...
 

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79 Case 406
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Discussion Starter #5
Ben,

Ooooh a notoriously bad part for around $30 !!!
That sounds like a good place to start that is in my budget. I will google it to see what else I find.

thanks,

Steve



Steve,

It sounds like you may have a failing ignition control module, they are nortorious on the older fords. The up side to this is that it should be fairly simple to replace (at least on the pickups), and I think they usually run like $30, so it is probably worth a shot if you can't get a better diagnosis. It really doesn't sound like a fuel problem unless there is a short in the injector wiring or a fuel pump relay going bad intermittantly, usually the fuel stuff causes them to run like crap all of the time.

Cheers,
Ben
 

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mogless, except for my friends MB4-94. And a bunch of other diesel junk.
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That ignition module is a POS, they go bad with no warning at all. Even new they are less than $75US. Should prob have this in PM so as not to anger the Mercedes Moderator. Your thoughts are spot on though, lots of smart people here to ask.. good luck
 

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79 Case 406
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Discussion Starter #8 (Edited)
I put OT (off topic) in hopes of appeasing the Mercedes Gods. I will do a high altitude Colorado 4wd mog trip report later this summer to make up for it.

Anyway, drove it to Advance Auto Parts yesterday after they told me they could hook it up to a computer and test the module. Barely made it as it was cutting out often. Turned out that 87s can't be hooked to the computer so I had to take the distributor out in their parking lot to get to the module. Their module test apparatus said it was good. By the time I got it all back together it was 8PM and I had to get on home with a rattling pinging engine due to not timing it. Maybe, possibly the connections were the problem as it seemed not to be cutting out on the way home. I will work on it more later this week. Thanks for all your help.

SG





That ignition module is a POS, they go bad with no warning at all. Even new they are less than $75US. Should prob have this in PM so as not to anger the Mercedes Moderator. Your thoughts are spot on though, lots of smart people here to ask.. good luck
 

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Unimog 421
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I have friends that luckily survived an accident when one failed at an inopportune time, and have experienced the problem myself. With that said, as previously mentioned it sounds like the TFI "Thick Film Ignition" module on the distributor, they go bad, and it's a heat problem. While failing they work fine when cold, but when hot the problems you'll see are ignition cutting out and a sputtering/stalling engine at idle or cruising speed - pretty much anytime really, which is exactly what you are having happen as I understand it. The link describes it in much more detail, but in essence testing it on the bench won't reveal the problem - the unit has to be heated to operating temperature for the failure to show up, adjusting the timing on the can bring it back to working for short periods. I did this on the one that was failing on me with some success, but ultimately the tfi module had to be replaced.
Stalling Car - Defective Ignition,TFI Modules,Sensors, Sudden Engine Failure Causing Stall - Recall & Injury Lawsuit
Replacing the unit will most likely fix the problem, but the best fix is to install an aftermarket distributor from mallory, msd or other manufacturer and get rid of the module altogether.
 

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Discussion Starter #10
I yanked the distributor out and replaced the Ignition Control Module, rotor and distributor cap. The problems all seem to be gone. Not a hiccup since.

Thanks to all for the help, you steered me right.

Steve
 
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