CLK55 won't start - error code P0112

[LostKiwi]

I look forward to changing my when the time comes

The one in the 210 (m112) took me about 15 minutes.....

 

[AMGeed]

Yep that's the method I've heard used for stuck ones.

This method works extremely well on stubborn spark plugs too.

 

[jpowell79]

Update on the nightmare I've had with the car. Couldn't get the CPS out for love nor money. After spending the best part of a week trying different things I finally gave up and had the car towed to a garage.

They had to drop the transmission to knock it out and put the new one in, however that made no difference, and the car still wouldn't start. The garage believed it to be a faulty ECU, but couldn't find anyone in the UK who would have a go at repairing it, so they shipped it off to an ECU specialist in Germany.

After a week, it got shipped back to the UK....plugged it in....still not working, so the garage called the German company, who were insisting that the ECU was fixed...in the end they agreed to taking a second look at it, so the garage shipped it back to Germany......The latest I heard was that it then got shipped elsewhere to another place in Germany, and now it's back in the UK, but from what the guy at the garage tells me, he's not convinced they have fixed it, but there's no way he can prove it, as when it gets plugged in it still doesn't work.

Have no idea where I go from here.....it's been over 2 months now since I've had my car!

Is there any point throwing more money at this?
Anyone had similar issues with their ECU?

Any suggestions greatly appreciated!

 

[alexanderfoti]

Its hard to comment on another garages work, espeically when we havent spoken with them directly.

However, if an MB engine cranks but does not start, it should be treated like every other engine.

If STAR shows that it has start authorisation (which it should if its cranking), then you need to check if you have spark/fuel and compression.

Now, if you have no spark, then the ECU is not sending power to the coils, or, there is an issue with the output stage of the ECU.

Causes for the above, are Cam/Crank sensors (as you say), which can be checked using a scope, or STAR for Cam/crank sync when cranking. In addition, if you see no RPM registered when cranking on diag tools, the sensor, or something related to it, is the cause.

If you have spark, but no fuel, then you need to check fuel side (pump/tank/lines/filter etc).

This is all basic stuff that the garage should have done. Have they given you insight into their diag route that led them to suspect the ECU?

 

[jpowell79]

Its hard to comment on another garages work, espeically when we havent spoken with them directly.

However, if an MB engine cranks but does not start, it should be treated like every other engine.

If STAR shows that it has start authorisation (which it should if its cranking), then you need to check if you have spark/fuel and compression.

Now, if you have no spark, then the ECU is not sending power to the coils, or, there is an issue with the output stage of the ECU.

Causes for the above, are Cam/Crank sensors (as you say), which can be checked using a scope, or STAR for Cam/crank sync when cranking. In addition, if you see no RPM registered when cranking on diag tools, the sensor, or something related to it, is the cause.

If you have spark, but no fuel, then you need to check fuel side (pump/tank/lines/filter etc).

This is all basic stuff that the garage should have done. Have they given you insight into their diag route that led them to suspect the ECU?

thanks for your response. They have told me that they have a STAR and that it's reporting the same fault code with CPS, however they have tried two brand new cranks sensors to rule out a bad one.

I see that you are only across the river from me in Dartford..... I might be in touch soon if I don't get this sorted

 

[alexanderfoti]

thanks for your response. They have told me that they have a STAR and that it's reporting the same fault code with CPS, however they have tried two brand new cranks sensors to rule out a bad one.

I see that you are only across the river from me in Dartford..... I might be in touch soon if I don't get this sorted

No worries. If possible, get the star error code they are seeing. We may be able to give more info based on that.

The code you posted initially was for a Intake air temp fault (P0112) so would be interested to see.

Absolutely ,just give me a call or send me an email.

 

[Wighty]

No worries. If possible, get the star error code they are seeing. We may be able to give more info based on that.

The code you posted initially was for a Intake air temp fault (P0112) so would be interested to see.

Absolutely ,just give me a call or send me an email.

He might have to walk over the Dartford bridge though , because his car isn't working

 

[alexanderfoti]

He might have to walk over the Dartford bridge though , because his car isn't working

You couldn't pay me enough to walk over that. I was recently wondering how they change the street lights on the bridge......

(we can arrange recovery of the vehicle for the op if needed)

 

[Steve@Avantgarde]

Well I'm not surprised it didn't work as you didn't do any diagnosis, you just guessed at a CPS as thats what it could be. Guessing just costs you more money in the long run, as you have now found out.

The intake temp sensor fault and the fact its logging a CPS is probably a stored fault because it won't go. Or the other reason is because when they were digging around at the CPS trying to remove it, they damaged the flywheel pick up. Something I have seen 3 times in the past. The way to test that would be to rig up a pico scope and check the pulse from the CPS and also check the internal resistance of the sensors to make sure they haven't been given a dodgy batch.

SO, its possible you have created the CPS fault yourself and you still have the original non running breakdown.

Because you get a non start the first thing people think is electrical, because of various sensors which control the engines running, and never check the basics.

Cranking and not firing...first thing I would be checking is the fuel pressure. 3.8-4.2 bar is the spec and there is a schroder valve on the injector rail to make it even more easier. The fuel pump relay has probably jammed or the pump has failed, both of which quite common on the 209.

 

[Uncle Benz]

I don't know if it's just me, but I watched the video, and it doesn't even crank. The next check is to see if the starter motor is being energised on the small wire. There seems to have been a lot of barking up the wrong tree on this thread.

 

[Steve@Avantgarde]

Fair play UB, i didn't see there was a video

Yeah, that was dead on key from beginning, but ignition twist, so I would be checking the fuse for the starter motor, and if thats good making sure there is 12v at the trigger wire in the front SAM. If thats ok I would be testing the voltage at the solenoid. If thats good I would condemn the starter.

If the 12v isn't there at the trigger then its likely a front SAM fault.

If its flagging a CPS now, then a fault has definitely been created, so now there are 2 faults to fix.

 

[alexanderfoti]

Not sure if we are watching the same vid? But its cranking in the vid I watched, just not starting.

Agree on all points.

 

[Steve@Avantgarde]

Not sure if we are watching the same vid? But its cranking in the vid I watched, just not starting.

Agree on all points.

I didn't have the sound on my laptop high enough I just rewatched it and yes it cranks over!!

FFS.

 

[Uncle Benz]

I didn't have the sound on my laptop high enough I just rewatched it and yes it cranks over!!

FFS.

Ha! Same here! It was pretty quiet!

 

[jpowell79]

quick update..... the ECU is now back from Germany (for the second time) and was apparently repaired after water ingress damage. The CPS error is now cleared but there appears to be a timing issue.

The mechanic said something about the timing being off by 10 degrees? He also said he needs to see if he can borrow a chain splitter from someone he knows at another Mercedes specialist garage to do the fix, as without it it will be a nightmare to do without it and the particular splitter he needs for this car is an expensive tool that they don't have at their garage.

I'm now at the point where I don't know if I'm being fed complete crap or not!

 

[alexanderfoti]

quick update..... the ECU is now back from Germany (for the second time) and was apparently repaired after water ingress damage. The CPS error is now cleared but there appears to be a timing issue.

The mechanic said something about the timing being off by 10 degrees? He also said he needs to see if he can borrow a chain splitter from someone he knows at another Mercedes specialist garage to do the fix, as without it it will be a nightmare to do without it and the particular splitter he needs for this car is an expensive tool that they don't have at their garage.

I'm now at the point where I don't know if I'm being fed complete crap or not!

If you have access to the car, it will be relatively easy to check the timing, if you can get the rockers off and the compare the crank/cam marks.

It would be the first m113 I have heard to jump timing. I think its more likely that the garage is not getting cam/crank synchronisation whilst cranking, and are making the assumption that the timing has moved, when I think its more likely the flexplate is damaged and giving incorrect information back to the ECU.

 

[jpowell79]

If you have access to the car, it will be relatively easy to check the timing, if you can get the rockers off and the compare the crank/cam marks.

It would be the first m113 I have heard to jump timing. I think its more likely that the garage is not getting cam/crank synchronisation whilst cranking, and are making the assumption that the timing has moved, when I think its more likely the flexplate is damaged and giving incorrect information back to the ECU.

The mechanic did say it was running now, just really horribly. Would that be a classic symptom of the damaged flexplate? Also, could it have got damaged from the work done so far? The reason I ask is because it doesn't make sense that the car worked perfectly, I pull up and run in the house to grab something quick, and then get back in the car and two minutes later it's doing what was shown in the video...... and now since then the ECU has been repaired and the CPS swapped out, and now suddenly the timing (or possibly flexplate) has gone? Just trying to understand how this could all happen in the space of two minutes!

 

[alexanderfoti]

The mechanic did say it was running now, just really horribly. Would that be a classic symptom of the damaged flexplate? Also, could it have got damaged from the work done so far? The reason I ask is because it doesn't make sense that the car worked perfectly, I pull up and run in the house to grab something quick, and then get back in the car and two minutes later it's doing what was shown in the video...... and now since then the ECU has been repaired and the CPS swapped out, and now suddenly the timing (or possibly flexplate) has gone? Just trying to understand how this could all happen in the space of two minutes!

There isnt really a classic symptom unfortunately. If the timing was 10 degrees out it would run horribly, lump at idle and hunting a lot, it at all, as 10 degree is quite a lot!

If its going to jump, it will be when the engine is started (or cranked) as the most likely time.

It is possible that the flexpate was damaged when the CPS was changed.

It wouldn't start if the cam/crank sync was too far out so there's that. They should check the CPS signal on a scope to check the flexplate isnt damaged etc.

 

[jpowell79]

looks like they've given up with trying to fix it

The mechanic is now suggesting that I get it towed to a specialist. The guy is a nice enough bloke, but I think their garage is a bit out of their depth with this one.

To make matters worse, my girlfriend starts her new job on Monday and needs her car back, so me getting to work as of next week will be a right PITA!

Alex, seeing as you are not too far from me, I'm thinking of arranging to get the car towed over the bridge to you if you're not too snowed under at the moment?

The mechanic at the garage said to get whoever I tow it to, to give him a ring and he can go through in detail all the stuff they've tried.

If you're interested, let me know and I'll give you a ring Monday morning. thanks.

 

[Wighty]

There isnt really a classic symptom unfortunately. If the timing was 10 degrees out it would run horribly, lump at idle and hunting a lot, it at all, as 10 degree is quite a lot!

If its going to jump, it will be when the engine is started (or cranked) as the most likely time.

It is possible that the flexpate was damaged when the CPS was changed.

It wouldn't start if the cam/crank sync was too far out so there's that. They should check the CPS signal on a scope to check the flexplate isnt damaged etc.

Alex , the op responded above , but didn't copy you in .