I have a multi hiccup pickup right now. It is a 1999 f 150 4x4 extended cab with the 5.4 liter and just turned 100k miles. For the last few months any time I kick my truck down to pass someone the battery light came on above 3800 rpm. Well three days ago I got my first service engine soon light. The code was Insufficient EGR flow. I did some searching and found most of the problems here were on 4.6 and 4.2 engines. I followed the same instructions and pulled the EGR, Throttle Body, and Upper intake neck. I cleaned everything out. It was all badly darkened, but nothing clogged. No large chunks to break loose. Well I went ahead and replaced the EGR valve and the alternator because my light was now on constant as of last night. I put the 130 amp alt on my truck, cleaned everything in the EGR system and replaced the EGR valve. I have not had a chance to drive my truck any distance to see if the light will kick back on, but on a short run I found it still has a slight hesitation feel in the pedal at about a 1/4 inch depression of the pedal that was not there just a few months ago. The light went out, but maybe it will come back. If it does, do I just go ahead and replace the EGR pressure sensor?

Also should I see any increased gas mileage with the new EGR if that was the problem?

One last question, mounted on firewall above the power brake booster is a vacuum block. This has a round **** of sorts on top of it. Does this adjust vacuum pressure? If so could it be adjusted to increase or decrease the flow to the EGR?

Thanks,

Rod

 

Sounds like the EGR DPFE(pressure feedback) sensor needs replaced, they've completely redesigned it, so it will last a lot longer.

As far as the vacuum thing above the master cylinder, it's a fuel system service port for doing diagnostic work.