Recently my car has been turning off or stalling when randomly coming to a stop and also a delay in revving when pressing down the gas pedal(Like when taking off from a complete stop there's a huge delay to get going). Though this problem is hard to duplicate as sometimes it idles smoothly at a stop. I've done a little bit of research and the most common problems are the RCM and the crankshaft position sensor. Well, I resoldered my cold points on the RCM and replaced the whole crankshaft position sensor - still have the problem. Since I've noticed my lights somewhat dim when getting the delay from taking off from a stop, I figured it had to be electrical and bought a new battery as well.... Yet the problem still persists. Getting a bit worried about this and would appreciate any help I could get on it.

 

No codes for Mass air flow?

 

​​​​​​​There actually is... But this also leaved me puzzled as I replaced the whole sensor last January due to those codes... I've also taken the same sensor out multiple times and used MAF cleaner on it to no avail.

 

Did you use a stock MAF? If so you have vacuum leak somewhere. The symptoms you describe are to the t for a bad MAF.

 

I'm thinking big vacuum leak or MAYBE unstable fuel pressure. My Ranger was doing this and it turned out to be fuel pressure, the pump was not running right due to corrosion on the circuit board that held the fuel pump relay. (The little transistor circuit that pulls the relay in was intermittent due to the resistive path thru the corrosion. The Crossfire is not the ONLY vehicle that leaks water down on the passenger side - and electronics get wet!)

THIS kit will tell you what the fuel pressure is (works really well for me cause it has two sizes of Schrader valves, the Ford Ranger size and the Crossfire size). Makes checking fuel pressure almost as easy as checking tire pressure.

https://www.summitracing.com/parts/otc-5630

 

THANK YOU SO MUCH! Hooked on an OEM Bosch sensor and the car is running smooth as hell! Guess I know now to always stick with OE Bosch and never go 3rd party. Greatly appreciated!

 

you're welcome. these cars are very picky about sensors.

 

We have a saying on this Forum about camshaft and crankshaft sensors, “Buy Bosch or walk home”.

 

Thankfully, when replacing my crankshaft sensor, I bought the OE Bosch part.
Guess I didn't have to invest all that money and time into my car. Does seems the crankshaft position sensor & solder joints on RCM were common problems with the XF and my battery was on the older side anyway - so I'm looking it as preventive care.

Thank you all for the information. Greatly appreciated!