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My 92 CE300 has had hard starting issues... seems like forever.
I bought the car from my father-in-law who chased the same issue for years with Mercedes mechanics, to the tune of $1,000's.
Car kicks over immediately and dies, sometimes 2 or 3 times, then will finally catch if I hold the starter for 5-10 seconds.
Then the car runs poorly for 15-20 seconds and then settles down and runs completely normally.
Was researching the issue and found a number of sources pointing to the cold start injector. It's a fairly expensive part... over $300.
Looked though all the paperwork from my father-in-law and it seems to be the ONE thing Mercedes didn't replace.
So today, I went to a junk yard and found a couple of cars with the injector and got them both.
Came home, cleaned them up and was going to install, but I can't get the one off my car.
Has anyone replaced this part? The blue one?
It appears it needs a 5mm allen tool, but can't get anything in there except a long allen wrench which just bends when I try to turn it.
Has anyone replaced this, and if so, what tool was used to remove the original?
As you can probably see, I've made a mess of this bolt now. No idea how I'm going to get it off.
Last edited by Boise300CE; Feb 27, 2021 at 08:56 PM.
My 92 CE300 has had hard starting issues... seems like forever.
I bought the car from my father-in-law who chased the same issue for years with Mercedes mechanics, to the tune of $1,000's.
Car kicks over immediately and dies, sometimes 2 or 3 times, then will finally catch if I hold the starter for 5-10 seconds.
Then the car runs poorly for 15-20 seconds and then settles down and runs completely normally.
Was researching the issue and found a number of sources pointing to the cold start injector. It's a fairly expensive part... over $300.
Looked though all the paperwork from my father-in-law and it seems to be the ONE thing Mercedes didn't replace.
So today, I went to a junk yard and found a couple of cars with the injector and got them both.
Came home, cleaned them up and was going to install, but I can't get the one off my car.
Has anyone replaced this part? The blue one?
It appears it needs a 5mm allen tool, but can't get anything in there except a long allen wrench which just bends when I try to turn it.
Has anyone replaced this, and if so, what tool was used to remove the original?
As you can probably see, I've made a mess of this bolt now. No idea how I'm going to get it off.
Are you sure it was a Allen head. Might be a torx head.
I would clean out the throttle control valve its the part in the picture with the arrow on it . Pull it out clean inside with carb cleaner or whitespirits.Make sure hoses are back in place after also look for split in the hoses at the same time.
I would clean out the throttle control valve its the part in the picture with the arrow on it . Pull it out clean inside with carb cleaner or whitespirits.Make sure hoses are back in place after also look for split in the hoses at the same time.
Thanks Trevor,
I actually replaced that unit, thinking it may have been the cause of my issues. No help.
Right so were loking at something else . Now cold start only operates for 4 seconds at start ,,so if this is not working right i wont make that much difference to start up cycle .What as been done in the way of engine temprature sensors . If thats toast it might be stuck and sending a message to the compuiter saying that your engine is hot,,, but in fact its cold ,,,.So as the computer sends the message that its cold the cold start cycle is no working as it should .. And all engine is getting is a weak mixture to start up on ...And another thing is the engine must be working at peek condition When was this ht system last tuned up --ie plugs ht leads etc . .. .Do you have the M104 lump in your car? Check you have a good seal on fuel tank cap . And no vacuum leaks .in the engine .
Last edited by Trevor Hadley; Mar 1, 2021 at 10:25 AM.
Right so were loking at something else . Now cold start only operates for 4 seconds at start ,,so if this is not working right i wont make that much difference to start up cycle .What as been done in the way of engine temprature sensors . If thats toast it might be stuck and sending a message to the compuiter saying that your engine is hot,,, but in fact its cold ,,,.So as the computer sends the message that its cold the cold start cycle is no working as it should .. And all engine is getting is a weak mixture to start up on ...And another thing is the engine must be working at peek condition When was this ht system last tuned up --ie plugs ht leads etc . .. .Do you have the M104 lump in your car? Check you have a good seal on fuel tank cap . And no vacuum leaks .in the engine .
Mercedes mechanics thought same as you and replaced the temp sensors and the computer. No help.
I put in new plugs, wires, distributor/rotor ~ December, so that shouldn't be an issue.
And yes, it's the M104 with the dreaded biodegradable wiring harness. That's my next project - starting to try to figure out how to source the correct harness.
Gas cap seal is good, it hisses when I remove the cap to add fuel.
Vacuum leaks are the devil.
Last edited by Boise300CE; Mar 1, 2021 at 04:38 PM.
I replaced my injectors and all parts involved .And like you with that bolt in the picture i damaged the one holding in the third injector and had to bend the injector holder to get the holding bolt out . You can spray the seals on the injectors to see if they are leaking ,i used carb cleaner to check the leak and if it is leaking then the engine will rev up a little .
Also on other models they have a WUR or - warm up regulator that helps at cold starts but i dont think you have one on your set up do you ?.
I replaced my injectors and all parts involved .And like you with that bolt in the picture i damaged the one holding in the third injector and had to bend the injector holder to get the holding bolt out . You can spray the seals on the injectors to see if they are leaking ,i used carb cleaner to check the leak and if it is leaking then the engine will rev up a little .
Also on other models they have a WUR or - warm up regulator that helps at cold starts but i dont think you have one on your set up do you ?.
No, there is no warm up regulator (that I'm aware of).
The car run perfectly, idles like a rock ~700rpm, accelerates and decelerates perfectly and doesn't hesitate on acceleration.
I'm pretty sure my problem is that cold start injector, but I still can't figure out how to get it out.
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