Del1650

Hello all,

I recently purchased a 1997 f150 supercab with 4.6 auto. The check engine light is on giving a p0401 code indicating insufficient EGR flow. I have done a lot of research and I took the throttle body off and found that the EGR passages were not dirty, I gave it a good cleaning anyways and put it back together (did not clear the problem). I have checked the whole EGR system including all the electronic components and hosing and they are all fine. The only problem that I have found is that the EVR solenoid is not getting any vacuum on the supply line. I am hoping to find out where this vacuum line gets its supply from? The line runs to the passenger side near the battery then attaches to a junction tree then continues on through the fender. I think there is a reservoir in the fender where this line gets its supply. I have done a lot of research and can't really find anything about the reservoir, I guess it is not that common of a problem. I am attaching a picture of a broken vacuum line that I found, Im not sure what this line controls but I think its some other function than EGR. Any feedback would be much appreciated. Thanks

Jbrew

I explained that to you yesterday. The EVR only pulls vac @ cruising speeds via PCM command.

And it does this quickly, then closes again.

Jbrew

I'll do yuh a favor, - everything you want to know is here, save this link, - it's very good and has GREAT diagrams with explanations, -

http://www.fordscorpio.co.uk/egrmonitor.htm

ibd2328

iTrader: (2)

Amazing what reading a related thread can do for someone.

Del1650

Thanks for that link it is a good explanation of the EGR. I have done a lot of reading about this and according to page 4 on the link I posted below, there are two lines attached to the EVR, a constant supply in and a regulated line out to the EGR valve. The line going in to the EVR should have constant vacuum on it even at idle (according to that article). I am not speaking about the hose coming out of the EVR to the EGR valve, I'm referring to the line going in to the EVR which from what I have learned should have constant vacuum then the EVR regulates the flow from that going to the EGR valve. On my truck this line does not have any vacuum. Thanks.

http://easyautodiagnostics.com/ford_...gr_valve_4.php

Del1650

The diagram on that article shows a line going from the EVR to the intake manifold. Mine does not go straight to the intake it goes to the passenger side behind the battery then into the fender.

Jbrew

Correct, and the red line is for the regulator vac on your model. Hang on.

Jbrew

In your other thread, on the other site, I referred to the Pink line being cut, BUT! It just looks pink in your crappy picture lol, - hard to tell. That's actually the light tan line which supplies the white line vac. You hacked it off at the solenoid for some reason. Obviously you can just do that and expect not to have repercussions. What did you expect lol. Anyway, fix it and you should be fine.

BTW- I doubt that's your reason for the 401 DTC, - makes sense and it could very well be, but I doubt it all the same. Not sure what else you hacked off. (?)

Del1650

I didn't hack it off it was that way then I bought it. It doesn't make sense because from what I have gathered that line is for the 4x4. I have used the 4 wheel drive and it works fine, I tried it again today just to confirm. Everything else seems to function as it should other than the EGR. I'm gonna try to inspect the emissions vacuum reservoir inside the fender well when I get time. Thanks for the help!

Jbrew

Well..... Why doesn't make sense? Think about it, - that other person or what not fubared it at the junction further down. That's alright, just remove the tape and protective cover to see what was robbed and re-spliced.

Pink and Blue = 4WD. That's what you'll find at the junction further downstream. Hard to determine EXACTLY what happened. Your pictures just show a severed line that isn't suppose to be. Go ahead and take and inspect the reservoir if you must, - doesn't hurt anything I guess lol. Then read my post one more time and try to listen. IF you want it fixed.

I'm done, this is probably useless.

Good Luck.