Author Topic: Stupid question of the day ... I can't start my car  (Read 211 times)

col320ce

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Stupid question of the day ... I can't start my car
« on: September 15, 2025, 09:48:25 »
250 auto. Last time I worked on it was a few months ago, and I had adjusted the accelerator pedal as I wasn't getting the venturi fully open.  After that and adjusting the linkages the tuning was out, but not terrible (it was stalling when warm) but it was startin,g and I was working my way through it.  The car has been idle for several months, and now when I try to start it it won't start.  The starter turns over and it sounds like it wants to start but just doesn't get there. I pulled one of the fuel lines off at the injector and looks like fuel is there.  I'm assuming it's an air-fuel mixture issue.  I used a battery booster and this helped a little.  I tried priming the fuel for some time.  I tried splitting the linkages to see if I could find a sweet spot whilst someone else cranked it.  I'm fairly confident I have air, fuel and a spark. Any thoughts?? 
Thanks
Col
Col

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Cees Klumper

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Re: Stupid question of the day ... I can't start my car
« Reply #1 on: September 15, 2025, 11:10:52 »
Maybe pull each spark plug to make sure fuel is getting to each cylinder. If yes, try a fresh set of plugs, but check each one to make sure each cylinder is also getting spark before fitting them (ideally without more fuel being injected into the combustion chambers, i.e. pull the fuel pump fuse) and take it from there.
Cees Klumper
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Raymond

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Re: Stupid question of the day ... I can't start my car
« Reply #2 on: September 15, 2025, 14:48:59 »
I agree with Cees except I'd start with checking for spark first.  I'm assuming you don't have an electronic distributor.  If the car is not attempting to fire, pull the Distributor cap and check the points for corrosion and dwell.  The ones supplied the past few years are terrible.  A 1-2-3 Ignition distributor is a valuable upgrade anytime. 

There is no such thing as a stupid question here.  It's how we all learn.
Ray
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rwmastel

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Re: Stupid question of the day ... I can't start my car
« Reply #3 on: September 15, 2025, 17:25:13 »
250 auto. Last time I worked on it was a few months ago, and I had adjusted the accelerator pedal as I wasn't getting the venturi fully open.  After that and adjusting the linkages the tuning was out, but not terrible (it was stalling when warm) but it was startin,g and I was working my way through it.

Col,
Let's start with what has changed. First, did you literally adjust the pedal?  How?  Second, you adjusted the linkages.  Were you trying to compensate for a problem, or trying to set them to factory spec?

I'd recommend following the Linkage Tour to set things to factory spec.  Measure the linkages, check for bent rods and loose sockets, etc.  Then diagnose problems from a known good state.

Checking for fuel and spark is obviously great advice.  Don't forget to check for fuel at the cold start valve.

Using the fuel, spark, and air appropriately is where having proper linkage setup comes in.
Rodd

Did you search the forum before asking?
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stickandrudderman

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Re: Stupid question of the day ... I can't start my car
« Reply #4 on: Today at 11:35:15 »
1st thing to do is get your helper to supply 12v to the cold start injector solenoid and see if there's any improvement.

col320ce

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Re: Stupid question of the day ... I can't start my car
« Reply #5 on: Today at 12:20:35 »
Got it started. The spark was there but it wasn't very consistent so I pulled the HT lead from the coil to the distributor and I think this was the issue. It was oxidised and a suspect the connection was poor. I also had to pull the spark plugs to clean them as they fat all gunked up in the process. Started easily after this!
Thanks for the help and encouragement!
Col

1964 230SL
1965 250SE coupe
1993 320CE Sportline
And George, the infamous 1992 Ford Laser

rwmastel

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Re: Stupid question of the day ... I can't start my car
« Reply #6 on: Today at 14:17:32 »
Col,

Great to hear! 

I'm still concerned about your gas pedal, venturi flap action, and general state of your linkage.  You might want to start a new thread regarding that.
Rodd

Did you search the forum before asking?
2017 C43 AMG
2006 Wrangler Rubicon
1966 230SL auto "Italian"

 

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