GEDaggett

hate to tell you this at this point but I could have saved you the money on the OVP. I just replaced mine to find out that it was not the problem and since you can't return electrical components I have one I could send you that is good. If you can send the new one back let me know and I can send this one out to you. As far as the engine mounts there is one under the exhaust manifold that seems to get cooked and goes bad before the other one. The mounts run for between $30 ad $60 depending on where you find them. They are a bit more invasive to replace as you have to raise the engine to takes the load off of them to replace them. Let me know about the OVP.

ZorroAMG

The thing about the OVP is that I most likely killed mine by jump starting it 5 or 6 times in the past few months.

Thanks for all the help guys....will update you as soon as the parts come in.

Bigpete123

Yo dude, to answer an earlier question of yours.

I think I might've been wrong about your car not having an MAS Control Unit. I looked through an online parts site and there is one listed for your car.

But you can answer the question very easily- it's located right by your battery. It has a dial on the top with an "I" and "O" imprinted on it. Obviously it looks just like the pic you posted.

Sorry for the potentially bad advice!!! Good luck to you.

appatula

I have had this issue plaguing me for over a year, erratic idle, and also hesitation under high acceleration. Spent a lot of time playing with the mixture screw and duty cycles to no avail. The EHA turned out to me my culprit, its located toward the back of the intake plenum, held by two Flathead screws. Make sure to shield your eyes as the residual fuel pressure will send fuel right into your eyeballs Once you have it out be sure not to lose the o-rings. There is a small copper/brass screw that you need to remove (Flathead) to get to the Allen adjustment screw, which if memory serves me correct is a tiny 1.5 or 2.5mm Allen key. At this point make sure you record how far you adjust this Allen screw so you can return to your original adjustment. In my case I turned the screw clockwise, thus giving a bit more fuel. The results? Along with no more sputtering idle and hesitation, my cold start dying is gone the car starts the very first time I turn the key without giving her gas

This is just a suggestion Z, however, many of us have been where you are now, and some still are but this is what fixed it for me. I'm also planning to give my injectors a bath in my ultrasonic cleaner and see if that smooths things out even more as injectors have been another culprit of idle issues.

RBYCC

Don't forget to check for vacuum leaks...
They are common on 124's as they age and create erratic problems.

Do you use an injector cleaner like Techron on a regular basis ?

Everything else just paint black....

ZorroAMG

Update:

I will be buying a new K&N (or cleaning kit) today along with a new fuel filter - Neither of which have been changed for at least 6 years lol. Once those are installed, if they don't fix my issues, I will do the ICV first, then the OVP. After that the fuel pump relay, then O2 Sensor, then hopefully all will be solved. If not, next after that would be Appatula's advice on the EHA valve. App, do you have a source?

Ed, I always laugh at your witty posts! Just call me Monochromatic Man!!!

I don't use injector cleaner...is that a good idea? I assume I can get it anywhere and do I simply follow the bottle's instructions or would you recommend some other way to proceed?

Checking for vacuum leaks by smoke test?

appatula

Source: http://www.mercedesshop.com/shopforu...&highlight=EHA

If you read through the whole thread you shall learn quite a bit about the EHA and how many W124 drivers have reported successful results.

I personally would not bother using any product claiming to clean injectors. The only route to go for injectors is to remove them yourself, and buy a nice 70USD harbor freight ultrasonic cleaner and try your best with that. A proper R&R includes new nozzles (non India/Thailand nozzles if you can find Bosch german ones) and flow tested to pop within 5-10% of each other. The Bosch nozzles made in Thailand and India are so inferior that the original German ones that have 100K+ milers on them usually flow, pop, and produce better spray patterns so I'd go the ultrasonic cleaning route.

RBYCC

Chevron Techron is a very effective injector cleaner and if I recall has been recommended by Merc and BMW for years.

Tier 1 gasoline usually contains the chemical component to keep injectors clean.

I've used Techron in my 300CE at every oil change for the past twenty years and the injectors have never been out for cleaning.

RBYCC

Monochromatic or not, you're still the man !!!

I use Techron at every oil change along with always using a Tier one gasoline.
Injectors will stay clean as well as the valves and cylinder head.

Smoke testing is the only way to find any and all vacuum leaks.
Smoke is injected into the vacuum system under pressure and wherever there is a leak you will see the escaping wisp of smoke.
Merc used some vacuum lines that become very brittle and crack with age.
Vacuum leaks are like gremlins, sometimes they leak and sometimes they don't unless they are major.
Always best to make sure you have no leaks before you start swapping out expensive components.

ZorroAMG

Thanks for the tips good sir!

appatula

I guess I can't argue first hand experience! I just remember reading some tid-bits in Graham Bell's "Modern Engine Tuning" that oil company's have been adding injector cleaning detergent to their fuel for years to reduce long term buildup. However in your case doing it over an extended period of time has benefited you. I do still believe that f the injectors are already plugged and or varnished, no injector cleaner is going to dislodge anything from those micro orifices.

RBYCC

Most first tier gasoline uses a PEA additive.
The gas tank treatment is a concentrate and will after a few uses clean injectors.

My first knowledge was in 1983 with a new BMW 318I.
Something about the head design which caused a lot of carbon buildup.
A factory bulletin was issued for dealers to remove and clean the combustion chambers and injectors.
Service department then gave me a case of Techron free of charge to prevent future problems.
BMW eventually made a design change that resolved the problem.


http://www.chevron.com/products/ourf...tives/tcp.aspx

Bigpete123

In my area, it's Shell and Chevron only for me. Chevron has the techron solution in all grades of its gas, whereas Shell has its detergent only in its highest octane gas (which I use anyway).

I too run a bottle of Techron through every 3,000 to 5,000 miles. As I posted earlier, I'm still having lots of idle problems, but for whatever reason whenever I'm running with a bottle of techron in the tank, the car runs significantly smoother (obviously this doesn't completely resolve the issues).

I've also had two independent vacuum tests done and no leaks have been found. So frustrating!!!

appatula

Interesting, I'll start using Techron on a normal basis

starcar

Me too!

YNVDIZW124

On my mustangs when i have carburator problems I go down the line. I would start with the fuel filter, fuel accumulator, eha valve, fuel pressure valve, fuel distributor, and fuel injectors.

I just readjusted my fuel distributor and throttle cables for more performance because gas prices went down so my car is running like a bat out of hell. I still have a little shaking but that's because i need new engine mounts. You're best source for parts is probably ebay and it won't help spending $3000 on dealer parts because it could be something as small as a O-ring under the fuel distributor.

Go to a shop and check for vacuum leaks and replace any hard rubber. Some things that can make your car run like this is the ignition module and coil.

ZorroAMG

Ok all,

Boooooourns. Yesterday, my car started acting CRAZY funny....major shuddering hesitation and stalling...had to get her back home with hazards on and put her in neutral to keep the erratic idle/rpms at bay.

I have ordered the following and when they come in, I will limp my car over to a shop:

Idle Control Valve
Fuel Pump Relay
OVP Relay
O2 Sensor
Fuel Filter
K&N

Thoughts? My Tank went from being wounded in battle to critically injured!

ps2cho

Based on the above -- OVP sounds like the problem.

Have you pulled your spark plugs and checked the color of them?

Just a thought -- Go check your Catalytic Convertor too. Very easy to check. Just slide under the car and give the big square cat half way down the car a bang with your first. It should be solid, no rattles.

ZorroAMG

I am a bit of a great DIY'er when it comes to modding and cosmetics but quite the n00b when it comes to mechanics. I pulled off the plug boot but what do I need to remove the spark plug? I have fairly limited tools, living in a condo...

YNVDIZW124

The OVP is not the solver of all problems. Your temp sensor has to be working and the EHA valve has the regulate the pressure on the fuel distributor. Sometimes the cold start valve will start to leak and your car will bounce once in a while. You may also have to change the seals around the fuel injectors because they get hard and start to leak too.

Make sure you go to a mechanic that doesn't try to change random parts thinking it's going to make it better. That happened to me the first time and i paid a huge bill and my car was the same.

berti_00

i went to buy that techtron as well but one older guy was there and told me that the REDLINE one is much better and that they were using at on their shop on cars so i bought one and poured it in well see if it does anything... i would hope so

190E 16V

Good luck, Rommel. Hope you were successful with the sparkplugs, today.

RHW

Just to mention...most inde shops make their living both selling labor AND profit margin on parts. Since I am not very mechanically inclined, I originally sought to save some cash by bringing ebay/internet bought parts to my inde.

It went okay once, the second time it took a long time to get an appointment (I'm thick and didn't realize why) but the third time, he told me flat out not to bring parts bought online OR allow him his margin or go away.

Also, an evaporator I bought online had an issue which cost a different mechanic some wasted time and we ended up tossing it. He showed me the issue to my satisfaction and I paid extra for his time wasted PLUS the new oem part.

Just saying, asking an inde to install your parts is asking them to work for less money. Some may roll with it, others may look for ways to get their money.

GET WELL SOON ENZO!

ZorroAMG

Hmmmm...good call. The last guy I dealt with, I said " I have some parts on the way, would you diagnose and install if necessary, paying you for labor and diagnoses" He was good with that.

Thanks for the heads up though!

YNVDIZW124

I had it two years ago when my ex mechanic tried to push $10 front wheel bearings for $50 each plus labor at $95-100/hr.

My advice is to know the ACTUAL price on the parts so you can know what mark up he's trying to push on you. Also some parts are pretty basic to change so even a regular 45-60/hr mechanic could change them and since they don't stock Mercedes parts they would let you bring your own.