Please read my other post about the car not cranking, it just started this last thursday and drags to crank when warm. If it sits for 30 min to an hour it will be very hard to crank but if you crank it and shut it off, and crank it again it will cran fine. Cold starts from sitting overnight are fine. Indy mechanic said it was the injectors leaking down, and try to run cleaner in it for 3 or so tanks to set a pattern. Said that it would cost me 1600 bucks to replace them and so I should just live with it or replace them if its not bad gas. I asked them to check the CPS but they insist its my injectors. ARRRGH!!!!
New Problem is that when I got it back from them, now my tranny shifts a little weird when going in third gear, rpms go up a little and it shifts and they fall back down. This happens when the engine is cold. Otherwise it shifts smooth. WAS NOT doing it before I took it to this shop!!!! On the drive here to south Georgia it was doing fine. In fact, the car has a new transmission from a year ago!!!! COULD THIS SHOP JUST SCREWED OVER MY CAR? All they said they did was replace distributor caps, rotors, and plugs.

I am hoping that someone here can please respond to our plee. I got advice here from someone and took our car back to the shop this morning andtold him to check the crankshaft position sensor, itcould be bad, but this mercedes place says it is not and its the injectors. They kept it all day andsaid the ran it through diagnostics. I am not believing this. My car was runing fine until I drove it down 3 hours from Atlanta, where I live. Thursday, on the way down, I bought gas at a truck stop off the interstate and that is when the problem started....could I have bad gas???? I talked to my mechanic that has the total history on my car back in Atlanta and he said he has been working on Mercedes for 37 years and has never replaced an injector on a V8 420. He said he would bet his money on a fuel pressure regulator. When you crank the car warm you smell raw gas and it smells of it out the tailpipe with some smoke. He said that it is the problem and will check it out when I get home.
Can someone here give us advice??? We are here in south Ga. and won't be taking the car back to this local indy mechanic, only other option is the dealer which I won't go to. My mechanic said that it will be ok to run the gas out and fill it up with some injector cleaner for now. Says it will smell of raw fuel like that.

Could this really be my problem???? We are learning about this car and my husband is baffled. PLEASE SOMEONE ADVISE!!!
Thanks to anyone that reads this.

 

How many miles on the car?Wish I could see and here what the symptoms are that you are telling about,When it has ran for 20 minutes and you shut it off and go into a store and try to start it,does it crank over fast or is it cranking real slow like a run down battery?Try to describe it like that.If it cranks strong and then slows down cranking rather quickly,have someone check the battery charge.I told you about the cps,if it cranks fast and keeps cranking fast but did not start until you wait like 20 minutes to cool down,CPS...Could be the fuel regulator,and if it showed up at the gas stop it could be bad gas,run a can of seafoam additive into the tank and fill it full with high test to mix it up,run it for an hour at hway speed,that will remove any water that may have been in the bad fuel.They probably did not hurt the trans,the other issues may be affecting the driveability.If this car was maintained,you should not be having this sort of problem,I wish I could help you more it is hard to fix some of these things online,so I feel your pain.Try the above,tell us more of what it is doing,find another indy can't be the only shop in the area.
ohlord

 

Hi again. I appreciate your info. We are worried because we are out of town with thecar and our regular mechanic is back in Atlanta, where we live. He has the whole history on the car and it has had every maintenance that was required andwe have all the receipts from it. This indy mechanic seems to be taking us for a ride, knowing we are here visiting and therefore wanting us to replace things on the car so wecan drive it back to Atlanta. BULL is what we all said! Wanting to charge me for a new set of injectors at 1600 bucks? NO WAY! That transmission was shifting awesome until I picked it up from this indy after having the plugs, caps, and rotors done.

What the car does is this. Cranks fine cold from sitting overnight. When its driven around town and stops for a few mins. (like 5-10 mins.) it will crank right back up, no issues. If the car sits any longer, like for 30 min to an hour or two, it will drag to start. Starter turns over and it just won't catch. It acts like its just struggling to come to life. It will finally crank though after two tries usually and holding it for like 8 seconds. Once it has cranked though and ifshut it off again, it will crank right back up without any problem. We have smelled fueland the independant mechanic we took it to said that when he tried to crank it, he smelled fuel and it was because of the engine being flooded with leakdown injectors.
This morning, Icalled my regular mechanic back in Atlanta and he said to not let this indy guy touch my car anymore, he said to bring it back to him because he thinks its the fuel pressure regulator and that is raw fuel leaking into the engine causing the smell and the hard warm start. He said he had never had to replace injectors on a V8 engine like ours. He thinks the indy where we took it to was trying to snow job us. The car has had a new battery too I found out.

With the transmission, I did find out it is still under warranty!!! Thank GOD...my mechanic told me the previous owner had it replaced and he was the one that had donethe repair. He said that it might just need an adjustment orsome fluid or that this other mechaniccould have knocked a vacuum line. It smeems to shift good except sometimes, the over rev from 2nd to 3rd but it shifts and accelerates fine.

Today we ran theold gas out and bought the cleaner, and filled it up withpremium. Will see how that goes until we can get back to our mechanic in Atlanta.

Thanks to these boards all the Mercedes Newbies really can ease their minds and learn from reading the posts!!!

 

Your tech is probably right, fuel pressure regulator on the fuel rail is probably bleeding off into the intake, Have them pull the vac. line off of it and see if it's leaking. I really doubt that the injectors are leaking. I've never had to replace injectors on a420 either.