Twice went to car show with 2005 srt6 runs fine going set at show 3 to 5 hours with hood open Go to leave engine starts, stumbles and shuts off like out of gas. It will not restart for several hours The next morning starts and runs fine. This has happened twice any suggestions I am afraid of getting stranded with this car. Vapor lock??????

 

Cold engine. Vapor lock. Unlikely.

 

Go to an auto parts store and have your car scanned as a 2003 Mercedes SLK 32, R170. The scan may give an indication as to were your problem originates. More than likely it will be in the saved DTC as you do not say your check engine light is on. Without a s scan/DTC it is just a guess.

 

My vote is bad solder or worn relays in the RCM. Get a new one and have DJ rebuild the old one for a spare. They are easy to change and plug and play. Do a search at the top of the page.

 

Thanks I will check that out. It seems it’s that or the cos or the fuel pump not holding pressure sometimes. I haven’t had time to do any checking yet. I will post things as I find them.

 

The RCM controls the fuel pump, but yes it doesn't hurt to check for pressure.

 

I checked. fuel pressure today at the rail. Turned key on primed rail it was 45PSI it dropped to 40 PSI in 30 min. It has stayed at 40 for the past 5 hours. Does these figures sound ok?
when you say it could be the RCM Is this the module located by the battery that has 5 fuses on top. If so is there a brand you would recommend I see Rockauto has 2 about $150. Thanks Dale

 

I ordered a new Standard brand RY-1562 RCM today from Amazon, it was $150 free shipping, due here Sunday.

 

I've got the same Standard RCM in my 2007 Coupe that I installed a few years back. The OEM RCM I sent to Tighe for repair & upgrade. It is my spare right now until I need it.

 

Start your car and check fuel rail pressure. With car running it should be up around 55~60 psi: your bleed down pressures at 40psi is fine. Yes, the RCM has fuses on top. It is located closest to the center line. The other two in there are the Body Control and the Power Control modules.
If you do not get 55 ~ 60 PSI with the car running your problem is with the fuel pump, OR the filter/pressure regulator. There are test to determine which is the culprit.

 

I installed a new RCM and the car starts fine. The only problem is so did the other one except on 2 occasions when I was some distance from home. I am afraid to drive the car and shut it off. How do I get in touch with DJ about rebuilding the old RCM?

 

email DJ Tighe at tighed1@hotmail.com

 

If it was the RCM, you are good to go now, just sent the bad one to DJ when you can.

If it was not the RCM, then I'd not go far from home till I knew it was right. So, what was the problem? Do you KNOW or guess it was the RCM? What did the car do or not do when it would not start?

 

Ok, just saw this.

When it stumbles and stalls, does the starter spin the engine over? If so, it's not likely the RCM.
I also saw your fuel pressure was 40 - not a good sign. Spec is 54-60psi with engine RUNNING. You should hold 36 PSI or more for 30 minutes, if not, you have an injector, pump or something not right.
An injector that leaks into a cylinder will cause misfires on startup.

My numbers here are not guesses, they are out of the service manual. If you can't get 54-60psi with the engine running, you need a pump and/or a filter/regulator. That is, if you have a new RCM. The pump relay on the RCM can go bad, but a new RCM rules this out.

 

But testing costs labor dollars, and besides, a car old enough to develop issues with one of those items is gonna develop issues with the other one.
You'd save time an a LITTLE money doing what I did: Had the pump and filter/regulator changed at the same time.

My Ranger finally died on me after being hard to start (ONLY when WARM). IT acted up for three years, it would start cold fine, but when warm, you had to park the switch at "ON" for 5 seconds, then go to "START" and it would usually start and run. Finally, one day in June, it died at a traffic light. Fuel pressure was spec at 62, it would start at 60 and fall to 18. Engine could idle at 25 but not really run and make power below 40."

New fuel pump/filter/regulator/pickup assembly cost $960 plus the $140 tow bill. But the truck is 17 years old and runs like new again.


Now, as to this guys car, we know that Crank sensors don['t like heat when they get old, but his CPS can't be THAT hot just sitting there.

 

At the first car show the car ran fine going sat at the show about 4 hours with the hood open went to go home started the car it stumbled and died right away. I tried to restart it would crank and crank and not start. One of the participants also a crossfire owner had his scan tool with him and there were no codes. He thought it might be week batteries in the key fob. I replaced th batteries and it started after some cranking and it ran fine going home. The second time it happened went to another car show same like before car ran great going sat in hot sun 3-4 hour with hood open went to leave exactly the same it started stumbled and died and would not restart.This time I checked for fuel by sticking a pen in the fuel rail schrader valve. I had no fuel pressure. I left the car setting on the street overnight came back the next day the car cranked and started immediately. I drove it home and it ran fine. After reading as much as I could find on the forum I felt RCM would be the best place to start. I did do a fuelpressure test It was 50psi at idle and not the 55-60 you quoted. So this is where I am at I did take the old RCM apart but the solder joints look good to me. I am still afraid to drive it anywhere that I have to shut it off.

 

It can also be the relays in the RCM. I always carry a spare for insurance, cheaper than a tow and fast to change.