scoobertdoo

He believes the issue may be related to the cob job I did in the trunk.
It did start the same time I did it, and the same time the pump quit running....
Any idea yet, or all just spectating on a wiring issue?
Seems when it is hooked up the coils get 6 volts, and when my cob is unhooked, they get 10 volts.

cmriv

cob? Try replacing all coils. There is another bulletin pertaining to issue that states to replace all coils. If coils don't fix issue you could always return them...

The affected coils might be in the production range with the date codes between 10T103 and 10T197.
The guided test will indicate the faulty ignition coil.

If the guided test does not produce any indication of a defective ignition coil (if a fault code is only stored), it may not be replaced and the real cause of misfire must be determined.

In a case of vehicle come back for failed coil(s), replace all coils.

Coils that failed and are outside of the production range indicated above failed for a different reason than that stated in the cause section.

scoobertdoo

Mechanic says that fuse 43 was popped, and its power on one side, ground on the other.
He will have to find where that wire is grounded.
Something to do with a fuel pump fan or something.

scoobertdoo

So he traced the wires, and found it goes to the radio diode under the hood.
He clipped that and the issue resolved.
Now the car will not start. He is thinking as he unplugged everything on the car he didnt plug something back in.
Poor guy has close to 30 hours into it. Told him I would give him 300, and I have not told him I will throw him another hundred when its done if it does not need an ECM.

He said it is not getting spark now.

VII

That is not a good mechanic, I mean he sounds like a standup guy but he is not good on diagnostics (On MBs anyway).
If you have 1 cylinder bank misfiring that usually means timing problems but its hard to say with the information given.
It sounds like you are determined to getting this back on the road and I'm sure you'll get there but this is not the most cost or time efficient path you are on...

VII

Btw please note there is no radio diode under the hood

scoobertdoo

He said thats what the wiring diagram called it.

scoobertdoo

Any idea why spark would be completely missing? I asked him to check the CPS to make sure it was plugged back in.

VII

At this point with the wiring having been edited that's probably it.
You might be missing a ground or voltage.
It could also be a timing sensor but I would not bet on it.
The ME can also have been damaged.
Buying a Star diagnostic is probably the best path forward. You can get one for 600 and easily re sell for 400 once you are done.

scoobertdoo

We are now in season two of the canonicals of the merc that don't chooch.
So three coils were burned up by low voltage, so they replaced them.
Then it went to mechanic two, he has a star scan.
He said the ECU has a high voltage alert.
He said the ECU is bad, and will send it to a guy to have it cloned onto a used ECU for 900-$1000
So right now the ECU is on its way to who knows where, in an attempt to clone it.

The new mechanic is a bit shady. He said the car needs new spark plugs because he tested the old ones and the resistance is infinite? Now, I have never put an ohm meter to a spark plug before, but with the plug having a gap, wouldn't a brand new one test as infinite? The kicker is he wants to replace them with Merc plugs for $29 each and 1 hour labor. I asked him why we cant use the same plugs from NAPA for $7 each, he said, "I dont use NAPA parts, they are junk"
I dont think this mechanic is very smart, I just think he is a scammer. We will see. As the bill is approaching $3000 and the car might not be repaired I am tempted to pay off the $7000 loan and walk away from the car, leaving it at the mechanics shop. If this magic ECU reprogramming does not work and the guy keeps upping the bill then it will happen.

VII

Spark plugs will measure infinite resistance from top (coil connect) to ground.
From top to electrode they should measure ~0 or 5k depending on whether they are resistor type.
In any case spark plugs don't go bad electrically...

cmriv

ill give you 1000 cash for the car. serious inquire as it doesn't run correctly and has an extensive list of repairs....

on another note, you should of priced a ecu at a dealership so it would have a 12 month unlimited mile warranty on it. Actually i think ECU's have 8 years 80k miles... or maybe that's for catalyst's... Either way i'm willing to bet the "clone" option isn't going to work as you'll need a D7 login to program it...


second mechanic sounds very suspect...

scoobertdoo

My feelings too on the number 2 mechanic. The first mechanic vouched for him. I started reading reviews of mechanic number two. Lot of reviewers that have only had one review ever and it was a 5 star for him. Then he has two that are 1 star, and they both say he overcharges, and gets angry if you call him on it. I have money for a lawyer if this sort of thing should crop up for me, but lets hope it does not.

He said he will have the ECU back in the next few days, and will install it and let me know.

My guess? He will say the car needs more work, and the problem is still there. At that point I will call him out on the ECU repair that was most likely not necessary.

No, not selling it for $1000, I am not on crack, and don't need crack money. Come talking with $5000 and you could very well own it, while I go buy a caddy.

cmriv

Well i guess you'll just have to sit and wait! Ask him where he sent ecu to... Like the name of the company.

Yeah, your ride does need more work. post #1....

and I'm not implying you are on crack by my low ball offer. But you did pay 6200 for that thing, and any one in the right state of mind wouldn't offer you anything more if they themselves could fix it. But i figured i'd try

on another note, you said the mechanic did a vacuum test and it showed a valve issue.... What vacuum test did he do? Is that also aka a compression test? And if your leak down readings still read in the "good" there still could be a valve train issue. IF remapped ecu doesn't fix issue i'm willing to bet you it's a bad valve seat or a burnt valve.



You had a no start issue at first
What is the spray pattern on the injectors?
When he did the leakdown did he for SURE make sure all four valves were closed? and or did he make sure piston rod was precisely straight up and down?
With doing the leakdown with out the valve covers on you completely remove piston rings from being the issue because you no longer have the crankcase sealed. With that said, faulty rings can as well cause a misfire...


to me, you got your 90$ worth of diag.... ya get what ya pay for!


bore scope the walls and head....

scoobertdoo

Waiting game now, Total from mechanic 1 is $600 including the coils he most likely blew up.
Mechanic number two is the wildcard.

scoobertdoo

Paid merc $200 and got bad information.....

cmriv

Nah you paid 6200$ for something you had no business buying. But you're stuck with it now so that is irrelevant. Your money woes all go back to you purchasing a high end German vehicle. couple that with fact you don't want to fork out coin to have it daiged by a Merk dealership.


Plenty have said run away while you can. But you can't go anywhere because you're paying for something you can't even drive. When will you get ecu back?

cmriv

you should have him bore scope which ever cylinder failed the so called vacuum test and see if there are any burnt valves....

scoobertdoo

It came back today, he will install it in the morning, and I am about 99.9999999% sure he will call me to tell me the problem remains. I will tell him I will come see him in person, and we will have a fight I am sure.

ml3504matic____

How's the condition of the car. Pics? That's quite a disaster. How many miles does it have?

Good Luck. Wish you and your car the best

scoobertdoo

Nearly flawless condition. 150,000 miles.

If it is not fixed today I may very well take the car home broken, and trade it in on something that is running. Not going to get much for it that way, but I am not going to give this guy any more money.

scoobertdoo

well... The news is goodish.
The ECM was replaced, and it idles normal, runs normal.
He said it still shows a missfire, but on 3 and 5 and not on 4.
He is having another ECM made, because he thinks the one they sent may be faulty.
He said on the old ECM, it does not run, on this ECM it runs.
So I will have a definitive answer next friday once he gets the new ECM from his guy in California.

cmriv

I'm confused. It idles and runs normal but shows a misfire? Elaborate.

scoobertdoo

Thats just what he says.
Could be like my motorcycle that needs plugs, it runs fine, but misses a bit at idle? Not going to quiz him, he calls me when I am working.
Should have the ultimate answer by Friday.

scoobertdoo

Will be nice to have it back, so I can start working on the small problems I knew about.
Air suspension is up first.