[W126 Coupe] Hesitance on driving

[Iain Gunn]

Get a tester and check the fuel pressure, It pigtails into the fuel line and 
duct tape the gage to the windshield, If my memory is correct it is about 
180 psi and about 80-90 when engine is off.
----- Original Message ----- 
From: "Sharan Bains" <sharanbains at hotmail.com>
To: <mbcoupes at mbcoupes.com>
Sent: Tuesday, August 09, 2005 12:25 PM
Subject: Re: [W126 Coupe] Hesitance on driving


> Hi,
>
> Thanks for the suggestions. I've been suspicious on the fuel pumps - but 
> all of the potential causes you listed, I will be checking for. My friend 
> is coming round on Friday so will update then.
>
> One of those things which needs a step-by-step diagnosis.....
>
> talbir
>
>
>
>
>
>>From: "Dick Spellman" <spell.yy at verizon.net>
>>Reply-To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
>>To: "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
>>Subject: Re: [W126 Coupe] Hesitance on driving
>>Date: Tue, 09 Aug 2005 12:15:29 -0400
>>
>>Hi Talbir:
>>
>>Well that does point to fuel vs. electric then.  Any thoughts I have would
>>be purely guess-work.  I am not much help on this subject I am afraid.
>>
>>You might want to try a can of BG44K after replacing the fuel filters and
>>run it hard for a bit to see if it's just something fouled up on the fuel
>>distributor.  Or perhaps you aren't getting enough supply (accumulators) 
>>or
>>one or more of the pumps is weak.  Leaky or improper set up on the EHA 
>>which
>>regulates the low side of the fuel distributor.
>>
>>Have you got access to a fuel pressure gauge that will read both sides of
>>the fuel distributor?
>>
>>Chet Hwilka was the MBCoupes master of fuel issues as I recall.  You might
>>want to run the archives for "Hwilka and fuel" in your query.
>>
>>Regards,
>>
>>Dick
>>
>>
>>----- Original Message -----
>>From: "Sharan Bains" <sharanbains at hotmail.com>
>>To: <mbcoupes at mbcoupes.com>
>>Sent: Tuesday, August 09, 2005 11:41 AM
>>Subject: Re: [W126 Coupe] Hesitance on driving
>>
>>
>> > Hi,
>> >
>> > It was before the work.
>> >
>> > The car had done 140k miles and it was still on it's old leads and
>> > injectors. So these were the first things to address.
>> >
>> >
>> > talbir
>> >
>> >
>> > >From: "Dick Spellman" <spell.yy at verizon.net>
>> > >Reply-To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
>> > >To: "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
>> > >Subject: Re: [W126 Coupe] Hesitance on driving
>> > >Date: Tue, 09 Aug 2005 10:43:42 -0400
>> > >
>> > >Hi Talbir:
>> > >
>> > >You don't say if this problem existed before doing the work specified
>>or
>>if
>> > >it has appeared immediately after the work???
>> > >
>> > >Regards,
>> > >
>> > >Dick
>> > >----- Original Message -----
>> > >From: "Sharan Bains" <sharanbains at hotmail.com>
>> > >To: <mbcoupes at mbcoupes.com>
>> > >Sent: Tuesday, August 09, 2005 9:53 AM
>> > >Subject: [W126 Coupe] Hesitance on driving
>> > >
>> > >
>> > > > Been working on a friends car - 560SEC Euro.
>> > > >
>> > > > New HT leads, dizzy cap, rotor and new injectors.
>> > > >
>> > > > When driving along at 40mph+, constant speed of say 60mph, then
>>there
>>is
>> > >a
>> > > > hesitancy every 2 seconds....it's like someone's gently dabbing the
>> > >brake
>> > > > for a split second, as there is a deccelerating effect. This
>>hesitancy
>> > > > appears at any speed.
>> > > >
>> > > > I've swapped the coil for a known good one (from my own 560SEC) and
>> > >problem
>> > > > persists.
>> > > >
>> > > > It's almost like one of the cylinders is not getting enough 
>> > > > delivery
>>of
>> > >fuel
>> > > > (idle is slightly rough too), which suggests a bad fuel 
>> > > > distributor.
>> > > >
>> > > > Any ideas ?
>> > > >
>> > > >
>> > > > talbir
>> > > >
>> > > >
>> > > > The MB Coupes Website!
>> > > > W126 SEC Mailing List
>> > > > Postings remain property of MB Coupes, L.L.C.
>> > > >
>> > >
>> > >The MB Coupes Website!
>> > >W126 SEC Mailing List
>> > >Postings remain property of MB Coupes, L.L.C.
>> >
>> >
>> > The MB Coupes Website!
>> > W126 SEC Mailing List
>> > Postings remain property of MB Coupes, L.L.C.
>> >
>>
>>The MB Coupes Website!
>>W126 SEC Mailing List
>>Postings remain property of MB Coupes, L.L.C.
>
>
> The MB Coupes Website!
> W126 SEC Mailing List
> Postings remain property of MB Coupes, L.L.C.
>
>