MAF = limp mode ?

Blownglass

New member
Rough idle

So my 2006 just recently started to run rough this last 2 days . Just got back from the snow park this weekend. It took over an hour for it to warm up to temp. First of all. Then yesterday it started to take a bit longer to start. A couple cranks vs just instantly
I thought it may be the fuel filter. Changed it but no real difference. Got some sea foam in it today not sure if it will fix it . . Just had to replace the intake air temperature sensor. Last week it ran great .
Rough idle at stop light now .
And odd starting behavior.

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Brokecanadian

2005 Cargo 2500 SHC NA
Re: Rough idle

So my 2006 just recently started to run rough this last 2 days . Just got back from the snow park this weekend. It took over an hour for it to warm up to temp. First of all. Then yesterday it started to take a bit longer to start. A couple cranks vs just instantly
I thought it may be the fuel filter. Changed it but no real difference. Got some sea foam in it today not sure if it will fix it . . Just had to replace the intake air temperature sensor. Last week it ran great .
Rough idle at stop light now .
And odd starting behavior.

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Does it lose power driving?

Extreme shot in the dark, I think this is pretty rare...had a rough idle and lost power on hills...traced it to the #1 cylinder injector wiring by manipulating the harness with the engine cover off

If you've got unexplained engine codes as well as shorted injector codes, that might be it...hard to tell unless you've got another clue, mine drove me crazy and I was convinced an injector was failing

Probably something else, but that was my experience

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talkinghorse43

Active member
Re: Rough idle

So my 2006 just recently started to run rough this last 2 days . Just got back from the snow park this weekend. It took over an hour for it to warm up to temp. First of all. Then yesterday it started to take a bit longer to start. A couple cranks vs just instantly
I thought it may be the fuel filter. Changed it but no real difference. Got some sea foam in it today not sure if it will fix it . . Just had to replace the intake air temperature sensor. Last week it ran great .
Rough idle at stop light now .
And odd starting behavior.

Sent from my Nexus 6 using Tapatalk
Sounds like an injector might be bad. First sign for me for all 4 that have been replaced to-date was surging forward at idle in gear. Also, puffing at the end of the tailpipe at idle (a hand near the end will feel for that). Run the injector leakoff test to pinpoint the probable bad injector. Also, I'd look at the clarity of fuel by draining a little from the water in fuel drain - you might have picked up some cloudy (wet) fuel that's causing problems.
 

Blownglass

New member
Re: Rough idle

Sounds like an injector might be bad. First sign for me for all 4 that have been replaced to-date was surging forward at idle in gear. Also, puffing at the end of the tailpipe at idle (a hand near the end will feel for that). Run the injector leakoff test to pinpoint the probable bad injector. Also, I'd look at the clarity of fuel by draining a little from the water in fuel drain - you might have picked up some cloudy (wet) fuel that's causing problems.
It does kind of surge at a stop .. doesn't lose power no codes praying for bad fuel.

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Seber

Member
Re: Rough idle

Mine had the same problem when I bought it. I dropped in half a bottle of injector cleaner additive and it smoothed right out. Cheap easy fix if it works.
 

Aqua Puttana

Poly - Thread Finder
Re: Rough idle

Mine had the same problem when I bought it. I dropped in half a bottle of injector cleaner additive and it smoothed right out. Cheap easy fix if it works.
I'll say it so others don't need to.

MERCEDES RECOMMENDS AGAINST SECONDARY FUEL ADDITIVES.

I added the BG 244 when my fuel gauge was a bit above 1/2 tank. I figure that to be roughly 13 - 15 gallons of fuel.

After 150 miles of running with the BG 244 it seems like my 2004 is now idling and running a bit smoother. That could be a placebo effect. What is not a placebo effect is that my latest cold weather starts no longer have the initial rough running and smoking. The engine starts normally.





So far it seems that the BG 244 diesel fuel additive has not destroyed my engine and may have actually helped some.

FWIW.

vic

Added: Reading some of the DPF discussions that mentioned high(er) RPM operation reminded me.

After adding the BG 244 to my 2004 I have been doing a bit of higher RPM driving by using lower gears. My thought was to keep the BG 244 conditioned (contaminated?) fuel flow through the injectors at a higher rate. Did it help? Would just driving and giving it the "thrash out" without the BG 244 have produced similar results? :idunno:
Well I suppose I have to confess I am sceptical of "snake oil" fixes!
But in this case the BG line of "fix in a can remedies", seems to work and add up to their claims.

So far as the 244 product is concerned I first used it as an experiement on my Missus' car a 2001 VW Jetta diesel. Now these beast are notorious for plugging up the EGR valve and inlet manifold.

A few 10,000 mile doses of it have kept the inlet tract clear and @ 200,000 Mls recorded of usual urban suburban driving the thing runs very clean and the E test center mentioned it had run very clean when it was last tested.

I was convinced to recommend it which I don't usually do that prefering to take Sailquick's position.

Cheers Dennis
...

Also once you are done add a can of BG's ATC plus transmission additive. Any abnormal burnishing of the lock up internal clutch will be smoothed out by this stuff.
All the best
Dennis
As always clicking on the blue arrow icon within any quote box will take you to the original post/thread.

:cheers: vic
 
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Blownglass

New member
Re: Rough idle

I have tried additives no help . Thought maybe it was choking for air. Put new air filter no change . Drives ok until I stop at light . Then is starts the UK and down idle and sometimes it knocks it is intermittent at times and other times it's every start and every stop light. I'm super confused

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Blownglass

New member
Re: Rough idle

If I give it a little press on the accelerator just the slightest bit at a stop light it seems to smooth out

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Brokecanadian

2005 Cargo 2500 SHC NA
Re: Rough idle

As was mentioned...if you're going to try and diagnose it yourself...try and borrow or buy a suitable Sprinter code reader...IMHO the sprinter is far too complex to guess

Did you perform the injector test?

While my MIL was not on, there were 42 trouble codes throughout my modules, helped me diagnose a bad engine harness
 
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Blownglass

New member
Re: Rough idle

I have the icar soft Mercedes code reader .. there are no current codes

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Blownglass

New member
Re: Rough idle

Didn't do injectors test.. any link to that procedure would be appreciated.im a few days into a road trip

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surlyoldbill

New member
Re: Rough idle

Doesn't a failing or bad IAT cause this symptom? Or disconnected ambient air temp sensor (behind front license plate)?
 

talkinghorse43

Active member
Re: Rough idle

Doesn't a failing or bad IAT cause this symptom? Or disconnected ambient air temp sensor (behind front license plate)?
The OP reports no codes.
 

Blownglass

New member
Re: Rough idle

Did the injectors leak down test. And all the injectors only put out about a 1/4 inch of fuel . 2 of them seemed to have no leak .

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NelsonSprinter

Former Nelson BC Sprinter
Yes, cleaning the inside with MAF spray cleaner can end LHM, or cleaning connection can end LHM too.
 

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