Another crank but no start dilemma
Another crank but no start dilemma
having read the numerous similar threads on this forum and as a new member I find myself with a very frustrating problem. For background, I have (actually my wife has) a low mile (14K) 2005 srt6 convertible. It has run like a clock since we got it in 2007. This year, getting it out of winter storage, I had to crank it several times before it would start (cold start) on 3 occasions. Once it started it ran perfectly fine. Finally, on the 4th attempt, it would no longer start (but cranks normally). I changed the CAM and Crankshaft position sensors (Bosch OEM new) and no change...it still just cranks. What's next? Help...I dread getting fleeced at a dealer and would love to find a DIY solution. Fuses look good, other electronics are working. Did I miss a step in the process? Disconnect the battery? Fuel pump (although I doubt it given the sporadic nature of the problem with normal operation once started).. any clues would be greatly appreciated.. thank you.
Re: Another crank but no start dilemma
There are two solenoid in the RCM that can fail, the fuel pump and another.
Can you hear the fuel pump when you just turn the key to the run position?
Re: Another crank but no start dilemma
You mentioned that the car was sitting. In addition to spark, the next culprit could be the fuel pump. The pump may fail (the fuse is fine so it would appear that the pump is fine too but it could be pooched or plugged with debris). If you have a jack and jack stands. It's easy to get at and they are cheap to replace. Be sure to relieve the pressure on the line before you disconnect it and always remove the Neg cable from the battery before you begin.
https://www.fcpeuro.com/products/mer...p-0004707894-1
If not, contact a local repair shop that specializes in MB and BMW. Every city has a few. Go to the shop, explain the problem and when it happens. They may be able to point younin thebright direction or correct it for you for an hours labour plus part.
Please keep us updated. I would like to know the cause once you've isolated it.
https://www.fcpeuro.com/products/mer...p-0004707894-1
If not, contact a local repair shop that specializes in MB and BMW. Every city has a few. Go to the shop, explain the problem and when it happens. They may be able to point younin thebright direction or correct it for you for an hours labour plus part.
Please keep us updated. I would like to know the cause once you've isolated it.
Re: Another crank but no start dilemma
Is the fuel pump not working? You should be hearing it as I stated earlier. If you give no feedback and just ask questions people will quit answering you.
Re: Another crank but no start dilemma
Sorry for the lack of feedback....Scheduling with work and other commitments gives me limited time working on the car, so I am trying to prepare and gathering all of the great suggestions before my next opportunity to get into it arrives (the next few days). So, I am very much appreciative in the meanwhile and will provide feedback as soon as I have the opportunity.
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Re: Another crank but no start dilemma
Turn on the key and measure the fuel pressure, or at least press the little button on the end of the fuel rail and see if there is pressure (But really, you want to know the pressure, book says 45 or more PSI is what the design calls for).
If the pressure is really low, the injectors wont' fire properly. I mean, face it, you need three things to start the car:
If the pressure is really low, the injectors wont' fire properly. I mean, face it, you need three things to start the car:
- Air. Air is drawn in by the engine turning over, if the timing chain is intact to run the vavles, you almost gotta have air
- Fuel. THe pump has to be providing enough pressure for the injectors to act.
- Spark. The plugs have got to be firing.
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Re: Another crank but no start dilemma
Check the cheapest items first so when an expensive part needs replacing you still have the money for it. Do not blindly throw new parts at the car.
Re: Another crank but no start dilemma
NO!
As mentioned, it's most likely the fuel pump relay (you DID check the fuse?) in the Relay Control Module.
For $30 I can fix it!
Send the pump back.
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Re: Another crank but no start dilemma
Again, NO. A relay with burned/dirty contacts will act just like what your saying. Seems your bent on replacing the fuel pump. All we ask is come back in if it fixes it, or not. Good luck!
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Re: Another crank but no start dilemma
Actually I've replaced quite a few relays where the coils go bad (open) once the relay has been energized for a bit. Now I apply 12 volts to the relays for a minute to ensure the relays work on the bench before I return them to owners.
You can close the relay manually to see if the problem goes away.
On a side note I've yet to see any other relay, other than the Air Pump relay with bad contacts. Have also noticed more frequently that the "on all of the time", Engine, Traction control and Fuel relays are discolored. Guessing that it's from the heat of the coil.
You can close the relay manually to see if the problem goes away.
On a side note I've yet to see any other relay, other than the Air Pump relay with bad contacts. Have also noticed more frequently that the "on all of the time", Engine, Traction control and Fuel relays are discolored. Guessing that it's from the heat of the coil.
Last edited by tighed1; 05-23-2017 at 09:33 AM.
Re: Another crank but no start dilemma
OK, a little more of an update...the fuel pump fuse is pristine as are the relays and solder points (no debris, no heat marks, intact solder). Remembering that this is a 14K mile cream puff. The case for the pump itself seems to be getting stronger unless I am missing something.
As far as the relay itself goes...As I look for a replacement on line, all I find is a 250 dollar unit. All of the other relays indicate that they are not compatible with the 05 crossfire srt6.
As far as the relay itself goes...As I look for a replacement on line, all I find is a 250 dollar unit. All of the other relays indicate that they are not compatible with the 05 crossfire srt6.