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hard to start unless blip accelerator

664 views 6 replies 3 participants last post by  plinker17722 
#1 ·
hello everyone,

I recently changed my thermostat and the temp is at 82C or so. the old thermostat was 71C which is not expected. I had also just changed the air filter.

Anyway, right after changing the thermostat I find starting is so hard. Eventually, I found blipping the accelerator just as I turn the key will help start the engine. Prior to this, no problem. just turn the key and it will start.

I have researched the problem and some suggested the OVP relay is broken. So I have taken it out. I found the fuse is still good. I tested it by connecting 12V, ignition and ground and I could hear the click. also, I have recorded 12V or so on the other pins. I have also put the relay back and have some one turn the ignition. I could feel the relay click when the ignition is turned. So, I am confident the relay is good.

Some have suggested checking the Cold start valve but have not gotten to it. I might just check that the valve is getting 12V across the pins.

Although I might add that I don't drive it much like once a week for about 20 mins. My hunch is that maybe the injectors need cleaning.

The car would drive with no problems. It's only the starting which is annoying.

Any thoughts and suggestions are welcome.

cheers!
 
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#2 ·
Just a note.....I replaced my air cleaner element and the car took extra cranks to get started. What could replacing the air cleaner element cause the thing to crank more before it starts.
I then remembered that I pushed down on that balance plate, but everything seemed fine.
It did this for a week and I had to remove the entire air filter assy....to inspect a leak at the valve cover.
I then sprayed carb cleaner on a paper towel and carefully cleaned around the balance plate. After I put everything back together, it starts fine.
Over here, we have summer gas and winter gas. Sometimes my car doesn't start right, or stalls....and I wait it out with the idea that I got a bad tank of gas. I'm lucky that my car always gets back to running good.
I try to put a bottle of Chevron Techron in the gas tank every oil change. Just for good luck, but the stuff works.
 
#3 ·
hi,

Thanks for the tip. I bought a can of carb cleaner, sprayed quite a bit and it starts easier.

I will try starting in the mornings and see how it goes. It's getting colder now that winter is coming. So all that gunk in the manifold may have been the culprit and the carb cleaner the solution.

cheers
 
#4 ·
o yes, just a little update. I also checked to see if the OVP is installed correctly.

I made sure the relay was seated correctly on the connector. In order to do that I removed the flap and a nearby relay before doing so.

outcome? easy starting either hot or cold. so far so good.
 
#6 ·
hi Trevor,

Thanks for the tip. I will be on the look out for it here in Perth, WA. I usually see Penrite in the local shops.

Anyway, I'm on to my next project: transmission service ie drop the pan, drain the torque converter, replace the filter and gasket. I will probably send it to the shop to do it. I think it's too involved.

The fluid is more brown than it is red. I think it's about time. 250k km on the clock.
 
#7 ·
ewee You can use what ever is in a good supply in you location . Its only a carbon cleaner from years ago .And i have used it for over 50 years or more in all my cars . Good luck with you car .. Wth your gearbox oil change lots of MB owners are useing Penrite oils for auto transmission. But if i was to do mine it would be Mercedes filter and fluids only ..
 
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