I sort of bought a car that sort of runs. A 1998 SLK230 looks like a good deal at night.

In reply to a_florida_man :

Hurray!  

It's no Chrysler Crossfire (or maybe it is) but its my favorite Gastro so far.  Its some what Aristocratic too.  

John Welsh said:

In reply to a_florida_man :

Hurray!  

It's no Chrysler Crossfire (or maybe it is) but its my favorite Gastro so far.  Its some what Aristocratic too.  

Indeed.

So to me, a legitimate part of the gastropod challenge will be to get all of the do dads working and the car detailed up nicely but cheaply. (Still want to buy SOME performance goodies ya know!)

I don't want to look like I'm slumming when I take Mazdeuce to the Taco Bell in it!! lol

AnthonyGS said:

a_florida_man said:

Project cars always look good on the trailer....

.....at night

at the gas station.

I nominate this as Seth's next T-shirt project......  silhouette of some miscellaneous car with the text beneath it.....  "Project cars.... always look good.... on a trailer..... at night.... at the gas station."    I'd totally rock one of these at the challenge and have photos to boot.

challenge (project) car looking good on a trailer at night at the gas station.....  in Wichita, KS.  I told you I had pictures.

They look even better when you stick two ugly ones in my trailer 

So, that last post reminded me of the unkown comic. When I found the 2 bag version, I could not resist.

Trailer selfies also make a project car look good.

a_florida_man said:

Sooo.... I got tired of waiting for my carsoft v12 multiplexer to arrive from Belgum, so I decided to poke at the MB with sticks. Or at least that's what I feels like to me when you can't access the REAL data stream. 

http://www.carsoft.com/carsoft-mercedes-v12-system.html

The problems that were presenting were:

No top operation.

No Horn

Signal Bulb Indicator On

Transmission in limp mode (2nd gear only).

ABS/ASR lights on

Brake wear sensor lit.

Codes P1747 No CAN BUS Data to Transmission 

            P0500 Speed Sensor A Error

 

So I jacked up the car and pulled the wheels for the first time, and found that there was a new wheel speed sensor on the front left. MMMMMkay

I also found that the RF brake wear sensor wire was broken.

I fixed that with two waterproof butt splices. $0.20 lol.

I have spent a lot of time reading on SLK and MB forums about issues that are common on these cars.

This led me to pull the k40 relay box. This is a relay board that essentially does the job of 5 relays and fuses. Nothing complicated, but it is annoying to have 5x the chance of failure.... anyway.

When I turned the car "on" only one relay closed. Interesting.

However, on the dash, the brake wear indicator was now out.

Good news.

 

I checked for 12v signals at the relay coils and 3 were actually being commanded on.

I knew the horn did not work.  I actuated the relay for the horn. BEEP!

Good News.

 

I checked and one of the non responsive relays was for the TCU  circuit.

I closed it manually and immediately the engine ran better.

Good News.

 

I held it shut with some cardboard and cycled the engine off and back on.

The  brake warning light went out and via the generic OBDII scan tool I read that the two codes were now clear.

Since it was up on stands, I put it in drive. It shifted 5 times.

GREAT news.

 

Next I tried the convertible hardtop, and whhhrrriiirr  click click buzz whhrrrhhrr clunk, it disappeared into the trunk.

Outstanding news.

 

That's a lot of stuff off of the list.

For the final fix I will either repair, modify, or replace the k40 Relay Module.

To reconcile the PO's experience.... they were being told that there was a wiring problem "between the sensor and the computer". That was wrong, and it is what happens when you use generic OBDII codes on an older German car. ( I also have a z3). LOTS of stuff gets lost in the translation. The REAL tools use OEM proprietary connections under the hood to access ALL of the modules.

 So a lot of time and $$ in parts I suspect had been tossed at the big issue (limp mode) until the owners just gave up. In the end it was just a bad relay that wasn't turning the TCU on. If the TCU wasn't on, it could not talk on the CAN bus (P1747) and report a speed (P0500). 

On top of all of that, the first step in the roof module logic is to make sure the car is not moving, and with no speed reported, it would just shut down and not open the roof.

The ABS/ASR lights are still on but I think that there is a good chance that they may only need to be reset with the proper CARSOFT interface now that the transmission reports a speed.

In the end it looks like this is going to be a GRM Gastropod entry for sure.

$1000.20 for the car and repairs to date..... now what's next?

 

This single post was one of the most exciting reads I've had in a while. Great troubleshooting and nice job!

Congrats on the troubleshooting! I examined that relay box on my mom's Crossfire when she had a no-start condition come up. We ended up replacing the box. They are available for a few hundred dollars max. I tried fixing the old one for shiggles first, thinking we could potentially return the new one but that didn't work.

One other item that may conk out on you is what Chrysler calls the SKREEM module - the box behind the gauge cluster that recognizes the chip in the key. It is a common failure in the SLK and Crossfire alike, although the Mercedes-branded part is far cheaper and easier to source vs the Chrysler-software-on-Benz-BS that we had to find.

Anyway. Love how all of the issues were basically tied to the TCU, but if you stop to outline the logic behind it all, it makes total sense. Enjoy it!!

Well, since the first round of 'repairs' went so well, I jumped into the first round of closer inspection and cleaning.

Found lots of mud, dirt, and a little oil.

I think is is in good shape for the most part, it has just never been really cleaned in the last 145k miles.

One of the biggest deals was opening up the cowl and clearing all of the drains. I think that almost every leaf that ever fell on the windshield since 1997 was in the cowl. I pulled out at least six full handfulls before it even made sense to start blasting with the hose.

Pure leaf litter from new leaves to dirt. I am sure one day someone might be happy I cleaned out the 3 drains today!

Under the hood, it was just an even film of dirty but slightly oily crud. Simple Green, soak, rinse, repeat.

The tray under the engine was NASTY. So I took a page from Mazdeuce's book and used some child labor. 

In the end Jack enjoyed the work.

He told me that he sees how it is fun to make old stuff new. I guess I'm starting something here....

I also decided that the fender emblem was just too cruddy to keep, and in fact there was not a lot holding it on.

Less is more.

Cleaned the headlights a little. Its getting so that it doesn't look too bad in the driveway....

​​​​​​

Budget to date $1000.20

Add two zip ties that had to be cut to access cowl (bought 500 for $20) 0.04 ea = 0.08

Total spent $1000.28

I should also add the cost of the new k40 relay, for now.

If I can fix the old one, I'll swap it out.

$1000.28

relay module $134.11

$1134.39

:)

I've got an idea for a David Letterman "Top 10 List".

"The top ten signs your aging sports car is on the cusp of oblivion."

Number 10:

You have 3 brands of tires, in 4 different models, and 4 different sizes.

Yep.

Now to be fair they are all 205/55/16. But due to the fact that they are all different models with different wear... well it just gets ugly fast. This might be part of the ABS/ASR issue too. We will see.

One other fact to consider here when you try to understand the sad state this was headed in...

The front wheels are 16x7 and the rears are 16x8. Now MB does make it optional as to what size you run on the rear:

So you might think, well to be frugal, run the same size and rotate the tires?

NOPE remember that the wheels are different sizes. Sigh. So, with this being a life long Florida car... why skip the  225/50/16 option?

Answer, to save $20 on the set.... :(

Miscellaneous stuff:

Im going to balance the tires this evening, mainly as a diagnostic for some of the ride noise and vibration issues.

Today was an oil change, transmission fluid change, and the wife's first trip.

SWMBO gave it a "green light" so things will keep plugging along.

I bought a replacement grill at LOWES. More to come on that. lol

Also, I found the 'SLK230' trunk letters in the center console.

That gave me an idea:

Tires again.... got to thinking.. treadwear...hmmm  lets go see.

420

420

260

820

That would be fun.... :)

a_florida_man said:

Tires again.... got to thinking.. treadwear...hmmm  lets go see.

420

420

260

820

 

That would be fun.... :)

 

I have to think a shopping cart wheel produces more grip than an 820-TW car tire. 

a_florida_man said:

Also, I found the 'SLK230' trunk letters in the center console.

That gave me an idea:

I dig it

re: Tuning ECU
It'll depend on how forward thinking MB was about applying ECU patches down the road, way back in '97... and then if any one has hacked it.  But, I'm going to guess that's going to be expensive... since it's a Mercedes, so the market for tweaking it is narrow, and aligned with the "spend big money" originally.

Alternatively, you can try and tweak the signals going into the the ECU... which can be really hit-or-miss, depending on the ECU.  Looks like you've got a little bit of a handle on the systems... but you're going to have really think through how fooling signals into the ECU will have knock-on impacts with other systems (as your recent diagnosis bout has already taught all of us).  I don't know how much lifting the top speed is going to be a priority for Challenge... I'm slowly learning that most of what makes a good drag pass happens in the first 500ft, or so.

In reply to sleepyhead :

I am encouraged by what I've seen in some MB forums.

I've seen folks sharing parameter maps, both stock and modified, which implies that they are able to compile flashable code...

I just have not ferreted out the method. My best guess is via the OEM MB STAR system.

The STAR system is out there, apparently you can buy a system with a legit MB hardware interface and a slightly less legit hard drive for a given dell laptop.

I'll wait and see what my CARSOFT system can do when it gets here, and investigate the whole process in the mean time.

My goal would have 3 parts:

1. Bring the SC in sooner, on early cars like this one it looks like the SC is slowly applied above 2000 RPM. I'm thinking closer to off idle. :) The MB system SC is controlled via a magnetic clutch, ala MADMAX style.

2. Bring the SC pressure up a lot sooner. The system uses a pressure bleed off valve back to the airbox to modulate SC pressure.

3. Raise the rpm limit. Right now its low, around 5 or 6k

I think MB was looking to be smooth and otherwise quiet with the SC application, as well as being concerned for low rpm torque and transmission life. The challenge goals would not be too worried about that.

I think the ASR system should have to earn it's keep... lol.

Very interested in what you find when you delve into the SC and how it works.  The mad/drunk scientist in me wants to put a 230k SC on a 1.8 air-cooled motor and see what happens.  I am quite OK with *BOOM*.

Next step... build a grille.

1. Old Emblem

2. Gutter leaf gaurd.

Hey, I'm half way there already....

a_florida_man said:

I think the ASR system should have to earn it's keep... lol.

 

FYI, the ASR on these sucksssss. It's like the old BMW ASC setup, where it just cuts throttle application 100% until it thinks you've stopped sliding somewhere. There's nothing really nuanced or good about it from my experience. Delete or turn off ASC and run good tires instead ;-)

Brake_L8 said:

a_florida_man said:

I think the ASR system should have to earn it's keep... lol.

 

FYI, the ASR on these sucksssss. It's like the old BMW ASC setup, where it just cuts throttle application 100% until it thinks you've stopped sliding somewhere. There's nothing really nuanced or good about it from my experience. Delete or turn off ASC and run good tires instead ;-)

Agreed. That was sort of tongue in cheek. And yes the ASC is bad, I have a Z3.... 

I can tell you that when it malfunctions it can CAUSE you to loose control. Ask me how I know and I'll tell you about a defective yaw sensor that tried to correct a spin that was not happening!

It's 'good' for the 'other drivers'.

AnthonyGS said:

Trailer selfies also make a project car look good.

Yes, best picture I have of my GTA

In reply to Daylan C :

Something about a car on a trailer makes you think, 'this car is important,...yes,something good is about to happen... just imagine..."!

So, after about 350 miles of road trials, a few simple things have been done, and a couple are on the list.

The little light on the dash that lets you know an exterior bulb was out, was on. That took a 194 and a 194na, $7.99

The instrument lights weren't lit up very well... 2 more 194's. $7.99

The AC control lights were out. These were a little tricky, you have to pull the knobs to access the bulbs. Easy once you know how. 2 new 2721 bulbs fixes that. $5.99

$1134.39 old total.

$21.97 new bulbs.

$1156.36 new total.

I also pulled the front seat, and reattached the upholstery to the seat base.

Cleaned under the seat, pretty clean for a 20 year old car.

Found some loose change, dumped it into the console. I'll add it up later.

Next steps will include addressing the driveline vibration.

Loaded is ok, but coasting (overrun) is LOUD. Coasting (neutral, unloaded) is silent. This points to the center carrier bearing, so I'll need to address that next. Probably pull the whole driveshaft and inspect the flex discs, u-joint and centering sleeves as well.

Also, hopefully this week my Carsoft v12 system should arrive. We will get more info on why the ABS/ASR light is on, as soon as I can actually talk to the system. Hopefully it is just a fault from the old k40 relay and a simple reset will be all that's needed. 

The cruise control is out too, but I expect that is secondary to the ABS codes. We shall see.....

a_florida_man said:

$21.97 new bulbs.

I wouldn't even mention this but you seem to be keeping a sort of challenge running budget total...

You might consider buying your bulbs somewhere else. You're looking at 10-20 cents per bulb if you'll buy them in boxes from RockAuto. I don't think I could stomach paying 7-8 bucks for a pair of bulbs.

In reply to Cousin_Eddie :

Agreed.

Not challenge smart... but honest.. :)

I wanted to fix it without waiting so I bough them from the local Advance OReilly Zone.

meh.