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HELP!..crank but no start

18K views 31 replies 8 participants last post by  Noodles 
#1 ·
I was driving to the store a few days ago and as i pulled in to the parking lot my car completely died out, as if it ran out of gas. I just filled the tank that day, so I know that wasnt the issue. Fuel level indicator showed a full tank. I also had the fuel pump (right side only) replaced a couple of months ago. Luckily, I was only a couple blocks away from home so I had it towed to my garage. I tried to start it again but still nothing. Checked fuses - all were good. Fuel pump relay is good - I can hear fuel pump running for a few seconds before I attempt to crank the engine. Fuel is definitely getting to the rail BUT I hooked up a fuel pressure tester and the dial barely moved. Could this be the cause? if so what needs to be replaced? I am a college student so budgeting is my best friend. Although, I do enjoy working on and getting to know my car. I also ended up replacing a few things that I noticed needed to be replaced. Minor oil coming from valve cover gaskets - replaced, including breather hose cover gaskets on both sides. Spark plugs - replaced - voltage is good. Also, I had battery and alternator tested. bad battery was replaced and alternator is good.

Hooked up to OBD and only got fault code for Throttle Position Sensor/Switch A Circuit High Input. Where is this sensor? Is this the issue? Another thing, I started it today after it had been sitting for a few days and a loud screeching noise came from something in the front passenger side below the SBC pump. it says Bosch PAD 12v. what is this?
 
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#7 · (Edited)
I think I recall that if there is no signal from the CPS,then the fuel supply will be shut down.
This makes people think there is a fuel system problem when actually there is not.
The op can hear the pump start up....
2003 M112 is very prone to CPS failure.
If possible,check the codes,,, P0335 indicates a bad Crank Position Sensor.
 
#9 ·
UPDATE!

First, thanks for taking the time to read my post and provide some insight to what the issue might be. It's greatly appreciated.

So, as some mentioned the crankshaft position sensor, I did some research and found that a lot of people had the same issue. Bought a new BOSCH OE CPS $30, less than 10 min to replace.

Car cranks but still doesn't start. THEN, next morning I tried again, NOTHING! The car no longer cranks. It sounds like it chokes or something is jammed. Any thoughts on what it could be?

Battery and all fuses are still good. I can still hear the fuel pump and jumpstarting doesn't work. I have an OBD 2 scanner and it gives me test results. PID or something with numbers and $ signs?

My weekend is free and I'm determined to get my baby back up and running. Let me know if you guys have any more suggestions. Thanks!
 
#12 ·
I would stop trying to start it or it will get very expensive.

If the starter gear is not in position correctly it may be chewing up your flywheel. That would be a major repair.
The starter needs to come out be rebuilt/replaced. Bosch makes a very good replacement for these cars at about
70% less than the Mercedes part which is made by Bosch.
 
#16 ·
I do see unusual wear on the flywheel teeth I can see, but it is not in need of replacement. They are the teeth with the fresh shiny metal showing. The surrounding teeth do not not show that wear pattern. The starter should be bench tested by a good rebuilding shop.

With the codes did the can say if they were pending, present or stored?

As far as the P0123 in some cases a throttle reset has worked. In other cases replacement of the gas pedal assembly is needed.
Try to RESET the throttle first. Follow the following steps:
1. Turn the ignition key to the on (NOT start) position.
2. Press the gas pedal to the floor and HOLD for five seconds.
3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.
4. Wait at least two minutes - don't do anything.

Once the starter is tested and rebuilt and installed you can try starting the car. Usually the P0123 does not keep the car from starting, but it can cause it. Most common is poor throttle response when using the throttle in regular driving.

The P0451 is possibly just the gas cap seal not sealing well anymore. It is 14 year old rubber.
 
#17 ·
I Work for a starter rebuilding shop

I Work for a starter rebuilding shop, what you're describing, that sounds like nasty grinding when cranking the engine over, that's a dead ringer for a failed starter drive clutch. basically the clutch itself slips and no torque gets transferred to the starter drive gear.

Thats a Bosch 10 tooth CW PMGR starter

Bosch PN for that starter is 0001108197
Letrika also makes that starter as well, they're an offshoot of Mahle. PN is MS171

They're Pretty pricey, a Bosch reman alone runs $200+ MY cost.

My (professional and experienced) 2 cents would be to take the unit to your HIGHEST RATED local starter rebuilding shop and have them quote a rebuild of the starter. I'm talking drive, brushes, solenoid, turn the com. those PMGR starters are super hearty, so you definitely shouldn't need to replace the armature. (its Perm Magnet so it doesn't have fields.)

Ask for it to be rebuilt with USA, Brazilian, or German parts ONLY, Chinese parts and Chinese replacement units are not worth your time, just trust me.

Your starter will be good as new and not have the $400-$500 price tag.

OH, and ask them to put a ZEN premium drive in that thing if they can get their hands on one. i'm showing one in stock from my vendor.

Best of luck man!
 
#19 ·
thanks guys for your help on this.

I replaced the starter and guess what? Nothing!

I didn't grind or anything. turned the key and it almost cranked but didn't. I heard the fuel pump then turned key to on position and it acted like the battery was dead. I just replaced it like a week ago. IDK what it could be. Maybe the timing? The answer is probably right in front of my face and I'm just overlooking it. User error? At least I am enjoying it, lol.

Mid-terms this week so I will be getting to it this weekend. Hopefully all this knowledge gets put to good use in my Auto-tech class.

Appreciate the help! If any other ideas come about, feel free to post. I'm open to all your help.

Cheers,

Hugo
 
#21 ·
No, the starter was definitely bad if you were hearing that grinding sound. A clutch can slip one day and be fine the next, usually depends on heat. starter drive clutch was on its way out. if the battery was dead, the starter solenoid wouldn't have engaged and the starter wouldn't have turned over and made that grinding sound to begin with.

I would put the car on the slow charger for like 6 hours or so just to rule out weather the battery's not up to snuff, that could cause all sorts of electronic gremlins if the cars running on low voltage. i had that happen on my CDI last year because of a crappy battery (different symptoms though).

Clarify this for us though....... is the starter still cranking the engine over? is it cranking but no start? or are you not hearing the starter engage at all?! because depending on which one of those symptoms you're experiencing, you're going to be looking at different solutions. My first thought if the car is not cranking, would maybe be an immobilizer problem with the ignition? if you have a second key for the vehicle try that out and see if the car behaves any differently.

if its cranking but not firing at all, i have a hard time believing that its a mechanical problem, like a fuel pump or anything like that. the fact that this happened all the sudden for you, that your car just stalled one day and you cant get it started again, i have a feeling that that's a sensor problem. something is telling the computer not to start the engine.

but take everything i said with a grain of salt, i'm a diesel guy XD
 
#22 ·
Ok so it doesnt crank at all..i feel something (maybe the starter engaging) and an audible clunk (like a punch sound effect..lol) and then i hear buzzing...almost like the fuel pump sound. It's like something is jammed somewhere and is stopping the car from starting up

I just replaced the battery a week ago and exchanged it for another one about 3 days ago
 
#23 ·
You said you replaced the starter already? The cluck (punch)sound you're describing sounds like the starter solenoid engaging, but the starter not turning. Hmm.

This is not solely a starter problem, the engine wouldn't have stalled due to a faulty starter. So that's a whole nother problem entirely.

Since this incident first occurred and you brought the car back home, has the engine been able to crank over at all? Or just this same click on crank you're describing?
 
#27 ·
Finally checked on my baby and she started but bogged out shortly after.

When I cranked the engine it started fine and within a few seconds the RPMs spiked then decreased over and over again until it died completely.

Made a second attempt to start it and it did the same thing. If i press the gas pedal it dies immediately.

Tested fuel pressure and it showed 56 psi.

I am still getting code p0123 tps switch a high circuit. With the live data option on scanner it shows 7.5% for throttle and im not even pressing down on throttle. It goes up to 21% when i do.

Tested injectors and coils voltage and resistance. All checked out to be good.

Also the scanner shows timing advance? -54 degrees then down to -15 degrees. Also, It sometimes shows -4 degrees. Not sure what that means or how accurate it is.
 
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