GDawgC220

http://www1.coe.neu.edu/~gkong/mbworld/idle1.avi --> right click and save as.

http://www1.coe.neu.edu/~gkong/mbworld/idle2.avi --> right click and save as.

please help me understand wtf happened to my car it wasn't this bad when i left work...

tpliquid

whoa that is cool!!!
my friends eclipse used to do that. it owuld jump rpms all the time. he changed out the rod bearing sleeves or sumitn i duno.. which kinda fixed his problem.

blackmercedes

DO you have a CEL on? If so, check the codes. Vacuum leak? Air Mass Meter? It would seem to be compensating like crazy. Does anyone know if 1994's can have adaptation values read? That idle condition make me think AMM or fuel pressure regulator thanks to the ECU trying so hard to control the idle. Must be a rich or lean like crazy condition...

GDawgC220

yep, CEL is on since Tues night afterwork, but @ that time, the car was totally fine. Same condition as it was before the light came on.

Yesterday after work, while stopped at lights or intersections, the RPM would dip and go back up, like if the A/C compressor was kicking on (HVAC was off). Thought maybe it had to do with it, but no power loss or the like.

After dinner, washed and detailed the car, started 'er up to pull back into the garage and thats when it started happening. I drove it around the block, no lag or loss of power. Just when idling in any gear, it'll start to do that

If I have it in drive and am standing still, the car will try and push it forward due to the increase in the rev's.

just called my SA, he thinks it may be the MAF (still on original one), so i'm dropping off the car after i get home from work and pick it up.

cil254

While it's idleing, give the MAF a few gentle slaps and see if it affects the idle, seriously.

GDawgC220

hmm...i will give that try before i bring it in tonight

i'll let u know how it goes.

blackmercedes

I don't think that the HFM system uses a flow sensor on the intake, but I could be wrong. I know the ME2.x system measures only air mass, and not the flow rate. I checked parts #'s, and the HFM and ME2.x systems intake air sensors are different, and luckily for you "early" C-Class owners, the HFM Air Mass Meter is less.

What I think is happening is that the HFM system is compensating for a rich or lean idle condition. This results in the increasing and decreasing idle. The car cannot idle (or run, eventually) as it relies on the information from the intake air sensor.

GDawgC220

hopefully i'll be able to make it to the shop.

if it was the airflow sensor, would you know how much would it run on our early w202s?

thanks man.

BTW, is the HFM the fuel system component? A year or so ago, I had the HFM fuel controller replaced...that wasn't a pretty penny

cil254

About $350 I think, and please don't pay any labour for this

blackmercedes

HFM is Hot Film, meaning the style of air mass metering set up. The ME2.x systems are not substantially different, but there are part # differences along the way. Also, diagnostic systems became more complex and sophisticated with the intro of OBD-II and the ME systems.

I'm in Canada, but I understand that the 1994 C220 AMM can be had for about $200USD, but I might be wrong. The later version for ME equipped cars is available on-line for around $325-350USD or so, and it's a five minute DIY job.

However! What if it's not the AAM? Then you're screwed, and have to begin troubleshooting all over again. Do you have a trusted indie mechanic? If so, ask if it's possible to buy the part through him/her, install it yourself, and return it if the swap does not solve the problem. Don't forget that a fuel pressure regulator will also cause AAM failure-like symptoms...

GDawgC220

I go to a independent MB dealer now where it's family owned and operated. They're pretty honest and up front about the problems.

When I dropped off the car this afternoon, it was doing the same thing and he said it most likely is the airflow sensor but will have it diagnosed tomorrow and give me a call.

I hope its nothing big because I can't afford to keep putting money into the repairs

sph17

but it was the A/C compressor cycling on/off.

This happened because the refrigerant was overpressurized. It would only happen when the ambient temp was over 90 F, and the engine was hot and I would be diving around town and stop at a store and the heat from the engine seeped into the A/C system. It would last until the radiator fan and the aux fan cooled down the engine compartment a bit.

But your A/C was turned off.

Holson

wow.. i'm amazed they haven't tried to sell you their black C230K

I think it's the MAF too, well.. good luck with the car! Keep it nice and shiny for the rainy Sunday GTG

GDawgC220

lol! hope i'll have the car back by Sunday and it is shiny but who knows for how long

miroj

Nah I think you better call a priest. Your car has been taken over :v by the spirit of a bygone era.

GDawgC220

lol.

outcome was the "airflow meter" gone bad. My SA said it was throwing codes everywhere so they took a while to eliminate areas where it wasn't possible and came down to the airflow meter. His words were "the airflow meter was so whack, it wasn't even funny" :p

they swapped it out, test drove it and worked like a charm.

Holson

sweet, so it'll make it to the GTG tomorrow! Hopefully it won't be pouring!



I had some hard starting problem with my car... and it'll go there on Monday - but... damn thing hasn't been doing that lately

DougandhisC280

I just looked at this thread for the first time. I was going to go with MAS as well. I'm on my 3rd one in a couple of years. There's three things that need to be recalled on early w202s. Head Gasket, Mass Airflor Sensor, and Wiring Harness. These three things seem to be giving almost everyone problems. If I was only a lawyer....

blackmercedes

Actually, recalls are only for safety related items, and none of the things on your list would be considered for recall. Mercedes did many "goodwill" repairs for head gaskets on M104's and wiring harnesses, but only up to 100,000 miles and for original owners, and only if the car had an excellent service history.

Where do we call a car "out of warranty?" Should Mercedes repair head gaskets on cars with 200,000 miles and are 15 years old?

I agree that the head gaskets on M104's and wiring harnesses on 92-95's are engineering defects, and Mercedes should have taken greater action to remedy the problems. They built their reputation on high standards of engineering excellence, and owners expect them to step up more than most other makes. But, in their defence, where do we draw the line? At what age is the owner responsible for the car? Mercedes cannot afford to have off-the-books warranties that are 20 years and 250,000 miles. No maker can.

No maker repairs the car past the warranty period.

DougandhisC280

Recalls are for factory defective items, not just safety issues. My mom's crossfire had a recall for the display on the radio. It looked black if you were wearing polarized sunglasses. I'm not sure that was for safety reasons.

blackmercedes

That's a voluntary recall for a defect. Chrysler was under no legal obligation to recall the cars. The US law is designed to force makers to recall cars only when it is a safety defect.

Mercedes has technical bulletins and they deal with many issues, but only rarely actually "recall" cars through a campaign like the ones you see other makers do. They only do a mass recall when it is a safety item.

Now, that does not mean they don't deal with items. Many of the defective wiring harnesses were replaced during warranty periods, and Mercedes replaced many more long after the warranty had expired.

They also update parts in an effort to ensure that problems are fixed, but this does not always work. There have been MANY versions of the head gasket for the M104, each one the "right" one. As we know, it does not always work.

The 722.6 transmission is the same. Mercedes is actively "not repairing" 97-99 722.6's under warranty. If your under-warranty car has a pressure control spring failure, it could be reapired very easily, but MB instead installs a new transmission, new ETC, etc. It's to get the latest tranny version into the car. It costs a great deal more, but hopefully gets most of the bad trannies out of cars.

The 3.5L six pot diesel from the 126 and 140's is a crap engine. High failure rate. Mercedes is just recently not picking up the tab for engine replacements. They footed the bill for mot of the cars long after the warranty had expired.

Today, things are different. Mercedes' cars are competitively priced (more so than in 1990...) and they don't have the margins to do some of the things they did in the past. In fact, many think (me included) that they hjave swung too far the other way, ignoring obvious defects hoping customers will just get to the end of the warranty before things go really bad.

Anyone see that MB has slipped to second from last in Three Year Reliability as rated by JD Power? Only Mitsu is lower! Just seven years ago they were in the top group, duking it out with Lexus. Now they're bottom feeders, chasing makers with cars costing 1/3. Great.

DougandhisC280

Anyone see that MB has slipped to second from last in Three Year Reliability as rated by JD Power? Only Mitsu is lower! Just seven years ago they were in the top group, duking it out with Lexus. Now they're bottom feeders, chasing makers with cars costing 1/3. Great.

This is true but don't worry. It will only improve the value of our cars for someone looking for a used Mercedes. New Mercedes just coming out are being built back the old way, to a standard, not a price point. Recent articles in magazines are proving this point. Mercedes was trying to reach younger buyers to improve their production rates. They instead made the wise decision to make Chrysler an upper class brand and market those to the younger entrepreneurs. Hense the Crossfire, 300C and Magnum R/T. All of these cars drive extremely well and are built to a very high standard but are thousands less than Mercedes. This now allows Mercedes to return to the high end car market and stop competing with ES300 and Acura RL. The 300C can do that and still blow it away. The future looks very good for the Daimler Chrysler Corporation.

miroj

Those rating agencies are tossers.