Cold start issues, and rough running when idling on warm engine.

Hello All,

I'm looking for some advice please, I have three issues with my 300GE, issue 1 & 2 may or may not be related. I have a 1995 300GE (463.228 variant) with the M103.987 engine (6cyl petrol).

Issue 1:

Cold Starting, the engine takes a little longer to start than expected, when it’s cold, a couple of seconds of turning maybe 3-5 secs sometimes. When it’s warm its starts absolutely fine. I suspect it may be the cold start value, or the electrics/relays to the cold start value? Could be the OVP relay?

Check that the one-way valve on the fuel-pump (the one under the rear nearside wheel-arch) is OK, The longer starting may be as a result of fuel draining back to the tank, requiring longer priming. But as mentioned by Rakesh, a good starting point would be to replace distributor cap, rotor, spark-plugs and possibly the ignition leads, if you don't know when they were last changed. The cap and rotor tend to last about 15k miles on these engines. Whilst under there, change the fuel filter.

Issue 2:

A bit more worrying, this has only happened about 3 times since I bought the car 12 months ago. Plus this ONLY happens when the car is warm.

When I come to a stop (i.e. idling) after I have been driving normally for some time, the engine idle drops very low, and the engine almost seems to ‘splutter’ and want to stall, in fact it has stalled once. Also when trying to pull away after this happens, it runs a little rough then settles into smooth running again (when it gains revs).

Sounds like the Idle Control Valve is dirty and sticking. Remove it, Clean it out with some petrol or alcohol and lubricate the internal rotor slightly with a few drops of clean engine oil and replace
.

I've googled the symptoms and it almost like a got sticky EGR valve, but funnily enough, it appears as if this engine doesn’t have an Exhaust Gas Re-circulation (EGR) valve! I could be wrong, but I’ve looked for an EGR value on the M103.987 and i can’t find one. Appreciate if someone confirm this please?

No EGR valve. thank god ! (unless you have a California engine)

It could be a number of things, perhaps the Idle Control value (ICR)? Bad Fuel pump relay (but why would it happen only when idling or coming to a stop from normal driving)? Poor fuel pressure? My suspicion is a faulty sensor or value somewhere. Or another bad OVP issue perhaps?

Issue 3:

Rear Wiper, the intermittent action does not seems to be working, when I turn the rear wiper on intermittent, it is constantly in action, and when I turn it off, it does not retreat back to correct upper position, it just stays where it was when I turn the switch off. Again I suspect it is probably a relay problem?

There is a wiper timer relay. this may be the problem

I did open the fuse box to see the relays, and I have seen a diagram of the relays on paper, but I have no idea which relay is which, apart from the OVP which is obvious to spot. Any help via pictures on identifying the relays (Rear intermittent relay and the fuel pump relay) would be a great help !

Any advice on these issues from all those experienced G owners out there and tech wizards, will be very much appreciated.

Many thanks

Athar