[MBZ] '88 126 Hesitation Problems and Intermittent Hard Start

[Kaleb C. Striplin]

Sounds like the throttle position sensor to me on the hesitation.  As 
for the idle deal, sounds like you are talking about the idle air valve 
that you had replaced.

Mark E. Peneguy wrote:

> Friends:
> 
> Recently, I started having a problem with hesitation when I accelerate 
> from a dead stop.  Once the car is in motion, everything is smooth, as 
> it should be.
> 
> I don't have a clue as to what may be causing the problem.  I have had a 
> few things worked on lately, including a tune-up, with new spark plug 
> wires and distributor, cap and rotor, etc., which seems to rule out 
> those things as the issues.
> 
> The only thing that I know made a difference in the idle, and I assumed 
> might be part of the hesitation problem, as the hesitation showed up not 
> too long afterwards, was a part (wish I could identify it for you) that 
> reduced the idle from 1,000 to 1,100 rpm at idle in park, to 550-600 rpm 
> at idle in park.  This part plugs in just under the air cleaner housing 
> in the front, top part of the engine, if that helps identify what it 
> might be.  The engine idles smoothly when in park, neutral or in gear 
> (runs about 450 rpm in gear at a stop and there is no "tremble").
> 
> My second problem is an intermittent hard starting problem (the starter 
> was replaced not too long ago and the problem just manifested itself). 
> Sometimes, I turn the key and it starts right up, like it always used 
> to.  Now, though, if it doesn't start immediately, I turn the key and it 
> cranks for a few seconds before it finally starts.  The last time that 
> happened, I saw smoke come out from the rear of the car (couldn't tell 
> what color, due to the ambient light).  That was the first time I've 
> ever noticed smoke come from the tailpipe in the 13 years I've owned the 
> car.
> 
> My trusted mechanic closed shop and is leaving the N.O. area since 
> Katrina.  So, I will be trying out a new mechanic to have this resolved 
> (wish I was mechanically inclined!).  I would like to have an idea of 
> what I may be looking at before I go to a new guy.
> 
> Any thoughts any of you may have shall be greatly appreciated.
> 
> Thanks in advance.
> 
> Mark

-- 
Kaleb C. Striplin/Claremore, OK
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