Does a Cold start valve go bad?

[dangol'benzo]

how do you check it?

190e 2.6 is a very very hard start when cold. sometimes it will crank after 10 mins of cranking, and when it finally starts, it idles perfectly. I can also shut it off immediately after it starts(engine still cold), and start it right back up, idling perfectly.

Ive been working on this car for awhile now...replaced OVP, MAS, plugs/wires, cap/rotor.

Ive tested crank sensor, temp sensor.

I can hear the cold start unit click when it has power...

I'd appreciate any help with this, thanks guys.

[Kyle Blackmore]

I had a similar problem with my 380SE, I replaced the check valve at the fuel pump, but it didn't make a difference. I finally replaced the fuel reservoir (accumulator) and this cured it. It began with hard hot starts, and eventually got to the point you're at. Do a search, there's a test to check it.
Hope this helps.

[dangol'benzo]

thanks for the reply kyle, I'll look into that.

My car actually starts just fine when warm, and actually starts fine every time after the first initial start. it just seems to be a problem with cold start.

[Cal Learner]

I agree that the accumulator is a likely place to begin, particularly b/c you say that it's only the first start that has hard cranking. A properly-functioning accumulator keeps the fuel system pressurized enough to open the injectors without a lot of cranking. If pressure bleeds off due to a poor accumulator, the fuel pumps have to run a while in order to re-pressurize the system, hence, long cranking times (altho 10 minutes I've never heard of). The quick test is to cycle the ignition key 3-4 times before you attempt to start the cold motor so that the pump runs each of those times and is allowed to build up some fuel pressure before the engine is started. If that test helps, you've identified a fuel pressure problem, almost certainly the accumulator.

To answer your original question, yes cold start valves can go bad like anything else mechanical (I've replaced one on my M103), but I don't think it's a very common failure.

[dangol'benzo]

very interesting you say that, Cal. because when I do get it started it is after I cycle the key on/off to get the pump pressure up. I'll test it today, thanks for all the help so quick guys!

[dangol'benzo]

Well, tested the accumulator. its good.

Just so im understanding, the CSV is very similar in looks to an injector correct?

Ive searched the hell out of this forum to find how to test it. lots of stuff for older cars, but nothing for this model.

they say that there is a hex plug to remove and see if fuel is coming out when running.

on mine, there is no hex head. nor can I get it running to see if it leaks.

I should mention also that this thing wont start AT ALL by spraying ether down the intake.

[pawoSD]

Remove it, aim it into a jar, and crank the car cold....it should fire some fuel. If not, its probably bad.

Usually the issue is the fuel pressure regulator, accumulator, or check valves.....

[dangol'benzo]

I read that on the old ones, there was a way to test if it was leaking. is there a way on this one?

[pmckechnie]

With a NO START, we start out with a can of CARB cleaner as a fuel (it's safer), spray it in the intake and if it starts, we have a fuel problem. If it doesn't start, we may have an IGNITION problem. We then check for fire with a test plug. No fire = NOT START. Next comes a compression test on at least 1 cyl. If good, then the only thing left is exhaust restriction. What it takes for a four stroke engine to run is FUEL, FIRE, COMPRESSION, and EXHAUST.
Think in terms of these 4 words and it will all fall into place and the engine will run. If this helps maybe we can help with the system that is failing.
Good luck
Paul

[azurite300E]

Not exactly related to this topic, but since fuel system pressure leaks has been mentioned, I wanted to share some knowledge.

On the M103 engine (and others) worn mechanical fuel injectors are also a common cause of system pressure dropping off fast after pump shutoff. Not saying this is the problem in this case, but rather then to also look elsewhere besides the fuel accumulator when there is an issue that prevents the fuel system from remaining pressurized on spec for at least 30 minutes afterwards. Basically worn injectors might start to "weep" fuel into the affected cylinders while the engine is off. To find the bad injectors they would have to be tested individually to determine which ones are leaking. This weeping sometimes manifests itself as hard hot starts, because besides of the pressure drop itself, on a hot engine there might also be pockets of air forming inside the fuel lines if the fuel is unpressurized, which contributes to the hard starting problem. Engine fuel flooding can also happen and make the engine very hard to start because excess fuel inside the cylinder(s).

Under the same condition cold starts would usually still be ok, but sometimes the engine just catches and then shuts off unless you "catch it" with the accelerator. What happens is that a bit of fuel puddles inside the leaking cylinder(s) and the engine first starts off with this fuel, but it's not enough to maintain combustion afterwards, so it stumbles and dies, or if there is excess fuel the engine just "bubbles" a bit after startup and then catches on and idles perfectly afterwards. After it initially dies, it usually is a bit harder to start the engine because it has to be cranked for a few seconds and wont start until fuel pressure has once again build up. Remember the fuel pump only runs for a second when you first turn the ignition key, and then only runs continuously on cranking or with a running engine, so it needs those additional seconds of cranking to be able to build up the pressure before the engine fires up once again.

The remedy of course in this case is to change all 6 injectors and seals, and if that was the problem your engine should once again start right off the bat every time and under any conditions with no more then one or maybe two seconds of cranking required.

Hope this info might be useful to someone. Corrections and/or additions are of course welcomed.

[dangol'benzo]

Originally Posted by pmckechnie

With a NO START, we start out with a can of CARB cleaner as a fuel (it's safer), spray it in the intake and if it starts, we have a fuel problem. If it doesn't start, we may have an IGNITION problem. We then check for fire with a test plug. No fire = NOT START. Next comes a compression test on at least 1 cyl. If good, then the only thing left is exhaust restriction. What it takes for a four stroke engine to run is FUEL, FIRE, COMPRESSION, and EXHAUST.
Think in terms of these 4 words and it will all fall into place and the engine will run. If this helps maybe we can help with the system that is failing.
Good luck
Paul

thanks paul. I actually had started a different thread, when I first bought the car 1 month ago. I bought it non running... Here is a link.

http://www.peachparts.com/shopforum/showthread.php?t=264898&highlight=190e+start


compression is 145 in all holes, Im getting great spark. the plugs are wet, so its geting fuel. When I first got it running, I drained the oil and put new plugs in. the oil had a alot of fuel in it, so my assumption was that it washed the cylinder.

My thinking is that the cold start injector/valve is leaking, and thus flooding the engine and leaking fuel into the oil.

[lkchris]

This isn't going to be an ignition problem.

Sounds mostly like your start mixture isn't rich enough.

"Cold start valve" is confusing terminology because you have to have two things happen

-an air bypass to create a faster idle (better term is idle control valve)
-a richer mixture

These are accomplished by two different processes, and if the richer mixture isn't happening, the air bypass makes it worse. You can't do without, of course, when the mixture is right, so don't spend much time analyzing the "cold start valve."

Besides of course looking for not-supposed-to-happen vacuum leaks, investigate if cold start *injector* is working. This is not the same component as the air bypass. IIRC the L-jetronic systems mostly just increase injection pulse time to create the richer mixture, but on this K-jetronic system there's a 7th injector to do this. It can go bad and so can the components that make it work, i.e. temp sensors, wiring harness, cpu, etc.

Clearly foot is off throttle during start attempts. No more air needed. But, if you really think it's flooding, then give it some throttle opening while cranking. It's a great test.

Normal fuel injectors should be in good shape in any event, but any "weeping" from them may actually prove helpful toward creating the required richer mixture. This weeping is usually only problematical for hot starts. The loss of retained fuel pressure caused by this is quickly corrected when fuel pumps work properly.

May also want to read: http://www.peachparts.com/shopforum/showthread.php?t=215486

[dangol'benzo]

THanks Kent, We are on the very same page. Im goning to pull that "7th injector" and see if it is getting fuel through it. should be a fine mist right?