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oneton
01-02-2016, 19:52
Ok, I'm in the process of changing out my Fuel rail pressure sensor. Bought a factory Bosch replacement but the design is different. The original had a provision for the washer/gasket to sit on the end where the new one is missing this. My question is, does the new sensor require the gasket as the original?

on edit: been thinking about this and wondering if what I am seeing on the original is the "crush" thru the center of the washer/gasket. Thoughts?

Thanks
David

oneton
01-03-2016, 12:13
Ok, dug up some pictures via google and the original is clearly machined for the metal gasket where the new one is not. WTH?




David

DmaxMaverick
01-03-2016, 13:19
Which one is like your original? The pressures involved require a metal-metal seal. Thread tape/paste or any soft seal won't work. It should have a metal seal or washer (crusher or not), IMO. It's difficult to say which is currently correct, as they frequently update the designs. If a low pressure sensor is used in place of a high pressure sensor, bad things may happen. Also, the PCM won't be happy with the wrong one, and it won't start if minimum<->maximum pressure is not sensed during cranking.

oneton
01-03-2016, 15:13
Thanks for the reply. The second picture is the original style. You can see the where the tip is machined for the gasket to sit on. I installed the gasket as required, just used to a mirror to make sure it push it all the way back and vertical.

As far as it being correct, everything I researched is that the new one is a correct replacement. In fact, the only place I can find the original part number sensor is Germany.




David

DmaxMaverick
01-03-2016, 15:47
I don't like reusing metal high pressure seals, but if it wasn't damaged and was properly torqued, it should be OK. You'll know soon enough. Wrap the sensor with a white cloth during the first start (make sure it's removed before the rail area gets hot). It will show any significant leaks very quickly. High pressure seal failure leaks are nothing to toy with. Keep your hands at least 8-12" away while running. Starting and idle pressure is north of 4K PSI, enough for a stream you can't see to sever a finger.

oneton
01-03-2016, 16:06
I used a new gasket, no worries there.

oneton
01-04-2016, 15:04
Well, no issues and no leaks.

DmaxMaverick
01-04-2016, 16:16
That's always good to hear.

Did the replacement correct the reason for replacing it? What was the reason? Inquiring minds want to know.....

oneton
01-04-2016, 20:18
Dmax, I had an excessive smoking issue. Graphing showed the FRPS was freaking out and the ECT sensor was reading a few degrees too high. Took a few trip up and down the road but the smoking has almost disappeared. Just have a few things to check out tomorrow with the Modis now.