Hello,

What are the symptoms of a bad fuel pressure regulator?

My car, 92 W201 2.3L has a weird issue.

When engine fairly cold, upon cranking the engine, the rpm needle will bounce from 0 - 4500rpm and engine will develop a "choke like" sound and then it will fire up.

If shut down right away and restarted, this does not happen.

What could this be?

I think it could do something with fuel. It gets in in bursts now continous? Hence I ask about fuel pressure regulator.

Idle control valve opens ok
All new breather hoses installed.
?

Fuel pressure can't cause those symptons.

Sounds more like an air flow position problem.

__________________
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Retired Moderator

As far as I know, the Fuel Pressure Regulator smooths out the flow of fuel from the fuel pump and also assists in maintaining fuel system pressure after the car has been shut off.

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Sounds ignition related. I would suspect an ignition coil based on what you describe.

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87 TDT 286k
87 SDL 195k
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00 122HP FLSTF
07 KTM 250SX

"Danger takes many forms"

You're hinking of the accumulator back at the fuel pump/filter package. The FPR restricts the free flow of fuel to create a predetermined pressure. The excess goes back to the tank.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.

MB DOC,

I used some carb cleaner on the throttle plate, but when I open it I can still see gunk underneath.

Do you think the dirt is blocking air flow sensor

Im pre-occupied with exams now, but whenever it is cold, close to the freezing mark, the car starts really funny

like I desribed, during cranking rpm needle will bounce up to 4 - 5 k rpm and engine seems like it is choking and then it starts.

Does this sound like something any of you encountered before?

Thanks for everyones input

Thanks for the reminder. I forget that this is a CIS system which necessitates a return flow feature.

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280