r129 sl 500.. engine cuts out when hot, starts when cold

[dellboy10]

Hi there Peeps,

Any top mechanic or a person who had the similar issue as my car!, its frustrating as i got a new engine put it.

one of the mercedes specialist has check it and said it the fuel distributor but that costs a bomb.

other forums say its a FUEL PRESSURE REGULATOR.
FYI i have changed the crank shaft sensor already but did fix the problem.



thanks

 

[ray_hennig]

What year is this car? Does it have a distributor?

If so, make sure the cap, rotor and leads are in 1st class condition and from MB, Beru or Bosch only. Also, make sure that plugs are exactly as recommended, not exotic platinum, iridium or other 'exotica'.

I had hot cut-out problems caused by cheap rotor arm.

Or maybe yours is a later car and I'm talking b0110cks.

Bonne chance.

RayH

 

[AMGeed]

Did you buy an OEM crank sensor or one of the eBay Chinese knockoffs?

 

[ray_hennig]

Did you buy an OEM crank sensor or one of the eBay Chinese knockoffs?

If it's a cheapo replacement, I'd put back the original, especially if it's an earlier car with KE Jetronic and distributors. The CPS on the earlier cars is pretty robust.

Also, start with the less expensive potential faults. The fact that your man said it might be the fuel distributor tells us it's a KE Jetronic with distributors.

Start with the HT. Rotor arm, plugs, cap, leads - probably in that order. And get the real stuff: MB, Beru, Bosch - in that order.

Good hunting.

RayH

 

[dellboy10]

Big thanks Pal,

the crack shaft sensor was from Bosch. i have replaced that.

Will work in that order... update you as each get replaced

cheers

 

[Vlad]

How old is the SL????

 

[dellboy10]

its a 1992 r129 SL500...

there is a cheap fuel injection distributor on Ebay, thinking of just replacing that. hopefully it will run normal. thats what the specialist advised me on.

 

[Bellow]

Has this symptom not occurred before and in that case been due to moisture in the (ignition) distributor cap that became mobile with heat?
A simple check (if it's not been done already).

 

[grober]

If it has the early EZL ignition system it may not be the engine that's "heating up" but the EZL unit itself-known to fail due to heat exchange paste between it and the wing drying out causing it to overheat- eventually it will fail completely- they can't be repaired- replacement is the answer IF this is the source of your fault.

 

[ray_hennig]

its a 1992 r129 SL500...

there is a cheap fuel injection distributor on Ebay, thinking of just replacing that. hopefully it will run normal. thats what the specialist advised me on.

I'm not convinced. Too drastic and doesn't square with my understanding.

Tell us again what you have done to resolve this and we'll start afresh.

RayH

 

[dellboy10]

Hi Peeps,

Anyone know a good R129 Specialist Mechanics near West Sussex?

cheers

 

[ray_hennig]

Hi Peeps,

Anyone know a good R129 Specialist Mechanics near West Sussex?

cheers

John Haynes in Worthing.

Have you had no luck in diagnosing the problem?

RayH