Won't start when hot

[1237jjm]

Hello there, I was hoping for some help from here since autozone offered no advice and i refuse to take it in. My 1994 ford ranger will not start when it's hot, it turns over just fine but no start. I have to raise the hood and let it cool for a while. It doesn't do this every time, but the frequency has been increasing. I recently replaced the fuel filter and ICM. Also, I'm not sure if this is related but every now and then (2 weeks or so) when shifting when I press in the clutch the rpms fly up even after making sure the throttle is let off before pressing the clutch. Any help would be greatly appreciated, thanks!

 

[warment]

My brother's 2000 ML320 did this when his Crank Position Sensor (CPS) went bad. It would run fine until he turned it off when hot. Then it wouldn't start back up immediately. As far as the high rev between shifts, my 2000 Mustang GT did this when the Differential Pressure Feedback Sensor (DPFE) went bad. On my car, it was a little black square box mounted to the firewall inside the engine compartment.

Not sure if this helps...

 

[1237jjm]

It does help, thank you for your reply. I'll look into the CPS. Also with the revs between shifts, when I pulled the codes the one came up was a problem with the EGR flow. I read that that one thing that could cause that code was the DPFE

 

[1237jjm]

After taking a look at my DPFE it looks like the rear tube goes about ten inches then stops and is sealed shut. Something tells me this isn't good..

 

[warment]

I am not sure what the DPFE sensor looks like on your truck, but I also had to replace the DPFE on my Dad's Ranger (2002 4.0). He had an error code indicating a bad DPFE. His was located on the front side of the engine on the driver side. Very easy to replace. Replacement on my Mustang was a snap too. Do you have a pic?

 

[warment]

And yes...the DPFE sensor works in conjunction with the EGR system I think.

 

[1237jjm]

Sorry for the hold up, I've got some free time tomorrow I'll get a picture then.

 

[1237jjm]

Here's the picture of what my dpfe sensor looks like although it's not the one off my truck. On my truck the front hose is connected to the egr tube off the exhaust. The back tube is not connected anything and is just sealed shut.

 

[Explorin94]

http://www.rockauto.com/getimage/ge...=0&dh=0&type=JPG&imagekey=1147135-0&width=450

Is that what it looks like?

Next time it is hot loosen the gas cap to see if it creating a vacuum in the tank.

 

[Kenneth S]

Next time when it's hot, and won't start pour some water on the cps to cool it off,then try to start it.

 

[1237jjm]

Well after replacing the fuel filter it hasn't not started on me all but once. But if it ever happens again I'll give that a whirl.

So where does the other hose go on the dpfe?

 

[Kenneth S]

 

[warment]

Read this...

http://www.explorerforum.com/forums/showthread.php?t=323238&page=6

 

[1237jjm]

Alrighty, whatever was intermittently failing has now failed completely I suppose. My truck will not start at all. It will turn over though.

Kenneth S when you say cps are you referring to the crankshaft position sensor, and if so where is it?

 

[Kenneth S]

Crank position sensor.