[SeanPlunk]

I have a friend that has a 1993 Mercedes 190e. He has replaced the battery and starter. When he starts the car he has to give it gas or it won't start. Once it finally starts, he needs to continue giving it some gas or it'll stall. The idle is very rough after that until it warms up. When he's driving it has no issues and he says it doesn't stutter or anything when he gives it gas. I'm thinking maybe the fuel pump is going. What say you motorgen mechanics?

[mustangray]

If I remember when I had my 2.3 16 cold rough Idle could be a couple of things one could be fuel pressure at the fuel distributor or a bad overvoltage relay one of the fuses might have blown

[Vettezuki]

I'd start with plugs and wires if they haven't been done in a while.

Then maybe a Seafoam treatment both through the intake and in the tank. If everything is all carbon'd to hell, the engine won't work so well thermodynamically. But that's probably not the cause of a hard start rough idle. Through the tank will help clean the injectors.

This is cheap easy stuff that can only help the car overall anyway.

I'm sure kdracer73 and others will have better input than this though.

[injdinjn]

If this was a carburated car I would check the choke, etc. Same thing on a computer car, I would check the cold start system.
I would also check around the starter area for a disconnected wire or damaged oxygen sensor.

[94cobra69ss396]

I had the same issue with the Suburban. It eventually got to a point where it would start. I replaced the plugs, wires, cap and rotor and that took care of the issue.

[kdracer73]

Originally Posted by mustangray

If I remember when I had my 2.3 16 cold rough Idle could be a couple of things one could be fuel pressure at the fuel distributor or a bad overvoltage relay one of the fuses might have blown

This is the most common failure for that issue...

Overvoltage Protection Relay
Overvoltage Protection Relay Fuse - Fuel Mixture,